JP2009262161A - Correcting apparatus, correcting method, control device, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a correcting apparatus that accurately detects remaining defects by using information relating to height and that automatically corrects remaining defects as necessary. <P>SOLUTION: An image processor 12 detects a defect on the basis of a defect image which is obtained by picking up an image of a glass substrate 2 by an imaging section 11, and recognizes a position and an area of the defect. A laser oscillator 14 outputs a laser beam for correcting the detected defect. The laser beam is subjected to spatial light modulation by a DMD (Digital Micromirror Device) unit 17 so that the defect is irradiated with the laser beam. A driver 20 for driving the DMD unit 17 is controlled by a laser shape control section 19 for outputting a control signal based on the data output from the image processor 12. A remaining defect detecting section 22 acquires height information relating to the height of the glass substrate 2 in the area of the defect, deciding presence/absence of the remaining defect to be further corrected after the correction of the defect on the basis of the height information. If the presence of the remaining defect is decided, laser irradiation is performed on the remaining defect in the same manner as laser irradiation on a defect. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for correcting a defect in a substrate.

  Inspection and correction of substrates in the manufacture of various substrates such as liquid crystal displays (LCDs) and flat panel display (FPD) substrates such as PDPs (plasma display panels), semiconductor wafers, printed circuit boards, and photomasks Is done. For example, after processing the substrate by the process A, an inspection is performed to determine whether there is a defect that impairs the function of the substrate or a defect that causes inconvenience to the processing by the next process B, and the defect is corrected as necessary. .

  In general, techniques for inspecting unevenness on the surface of an object to be inspected include techniques that repeatedly use illumination of bright and dark patterns, and techniques that use the length of the shadow formed by irradiating collimated light from an oblique direction. It is known (see, for example, Patent Documents 1 and 2). A confocal microscope is also known as a technique for measuring fine irregularities (see, for example, Patent Documents 3 to 5).

Further, there is known a correction device that corrects a defect on the substrate by irradiating a defective portion on the substrate with laser light, and is also called a laser repair device.
However, even if the laser repair apparatus performs laser irradiation for correcting the defect, the defect may not be completely corrected. For example, when a defect is irradiated with laser light that is weaker than the output necessary to actually remove the defect, a part of the defect may remain without being removed. Hereinafter, such remaining defects are referred to as “residual defects”.

  Therefore, it is required to determine the presence or absence of a residual defect and correct it again if there is a residual defect. A method of using optical density (luminance information) or an image for detection of a residual defect is known, and a method of registering a region of a residual defect by a manual operation using a drawing tool is also known (for example, Patent Documents 6 to 6). 8).

  However, it is difficult to automatically operate the laser repair device with the method of determining the presence or absence of residual defects based on the captured image obtained by imaging the substrate after laser irradiation to the first detected defect. Inspector intervention is required. This is because the residual defect may be erroneously detected even though there is actually no residual defect. A typical example of false detection is as follows.

  When the laser repair apparatus irradiates a defective area of a substrate, which is an inspection object, with a high output laser beam, a burnt surface may be generated on the surface or the base of the substrate. The burnout may be on the surface of the remaining defect, or may be on the surface of the substrate or the substrate after the defect itself has been completely removed.

  When determining the presence or absence of a remaining defect based on a captured image, it is difficult to accurately distinguish between a burnt eye and a remaining defect. This is because the brightness of the burnt eye and the remaining defect is similar in the captured image. Therefore, the laser repair device may erroneously detect a burnt eye as a remaining defect. Actually, even though the defect was completely removed by laser irradiation, if it was detected as a remaining defect due to burnt eyes, this resulted in unnecessary laser light being emitted, and again the burnt was detected as a remaining defect. Is done. Therefore, it is necessary to prevent the detection of residual defects and laser light irradiation from being repeated indefinitely. For example, the upper limit number of repetitions is set in the laser repair device. However, even in that case, detection of remaining defects and unnecessary laser light irradiation are repeated up to the upper limit number of times, and extra time is consumed.

Therefore, the following operation method has been adopted. That is, the laser repair device displays the captured image on the monitor. Then, the inspector looks at the monitor, and finally determines whether the detected residual defect is an actual residual defect or a burnt eye. If it is determined that the defect is a residual defect, the inspector performs a repair operation for the remaining defect area, registers the area of the remaining defect, and instructs the laser repair apparatus to perform re-correction.
JP 2003-329428 A JP 2005-274256 A JP 2000-275530 A JP 2004-184342 A International Publication No. WO 97/31282 Japanese Unexamined Patent Publication No. 1-219751 JP 2005-103581 A JP 2007-29983 A

  From the viewpoint of shortening the time required for defect detection and correction, it is desirable to eliminate the need for inspector intervention in a correction apparatus for correcting defects on a substrate. For this purpose, it is necessary for the correction device to automatically and accurately distinguish between actual residual defects and burnt eyes.

  A defect that is corrected by laser irradiation is a type of defect in which an extra substance exists on the substrate, and is corrected by removing the extra substance from the substrate by laser irradiation. For example, in the case of a defect in which the resist film residue causes an electrical short in a circuit formed on the substrate, the resist film residue is a substance to be removed.

  In other words, both of the first detected defect and the remaining defect are portions that are raised from the original height due to some extra material existing on the substrate. In contrast, burnt eyes change the appearance color but do not change the height. Therefore, if the information about the height is used, the remaining defect can be distinguished from the burnt eye.

  Accordingly, an object of the present invention is to provide a correction device that can accurately detect a residual defect by using information on the height and can automatically correct the residual defect as necessary.

  According to one aspect of the present invention, a first correction device is provided. The first correction device detects a defect to be corrected in a substrate to be inspected, recognizes a position and a range of the defect, and height information regarding the height of the substrate in the range of the defect. Based on the height information, it is determined whether or not a remaining defect to be further corrected exists in a part or all of the range of the defect after correction of the defect detected by the defect detection means. A residual defect detecting means that corrects the defect when the defect detecting means detects the defect, and a laser for correcting the residual defect when the residual defect detecting means determines that the residual defect exists. A laser oscillator for outputting light, and the position of the defect so that the laser light output from the laser oscillator is applied to the defect detected by the defect detection means. Two-dimensional spatial light that spatially modulates the laser light according to the range and spatially modulates the laser light such that the laser light output from the laser oscillator is irradiated onto the remaining defects on the substrate. Modulation means.

  According to another aspect of the present invention, a laser oscillator that outputs a laser beam for correcting a defect on a substrate to be inspected is provided, and a function of irradiating the laser beam to an arbitrary range on the substrate is provided. A method is also provided for when the second correction device performs the same function as the first correction device.

  According to still another aspect of the present invention, a laser oscillator that outputs a laser beam for correcting a defect on a substrate to be inspected, a two-dimensional spatial light modulation unit that spatially modulates the output laser beam, and The control apparatus which controls the 3rd correction apparatus provided with this is provided. The control device controls the third correction device to function in the same manner as the first correction device.

  Also provided is a program for causing a computer connected to the third correction device to function as the control device in order to control the third correction device.

  In any of the above aspects, whether or not there is a remaining defect is determined based on the height information, so that a burnt eye having no height and an actual residual defect having a height are accurately distinguished from each other. . Therefore, it is possible to accurately detect the remaining defect. Therefore, a series of operations of defect detection, defect correction, residual defect detection, and residual defect correction can be automated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, for convenience of explanation, each embodiment will be described by taking a laser repair apparatus that uses an FPD glass substrate as an object of inspection and correction as an example. However, the target substrate may be another type of substrate such as a semiconductor wafer.

First, a first embodiment will be described with reference to FIGS.
FIG. 1 is a configuration diagram of a laser repair apparatus 101 according to the first embodiment. In FIG. 1, a solid line indicates a flow of control and data, and a dotted line indicates an optical path. The same applies to the following figures.

  The laser repair device 101 holds a stage 1 that holds and conveys a glass substrate 2 to be inspected and corrected, an imaging optical system that magnifies and images the glass substrate 2, and a defect on the glass substrate 2. The laser irradiation optical system and a monitor 13 are provided. The imaging optical system and the laser irradiation optical system may share some optical elements. In the first embodiment, the beam splitter 8 and the objective lens 9 are shared.

The laser repair apparatus 101 also includes components that perform various types of data processing or control, and further includes a residual defect detection unit 22 that detects residual defects.
In the following description, the “residual defect” is a portion to be further corrected after the initial correction for the defect detected on the glass substrate 2. For example, when the laser power for correction with respect to the initially detected defect is insufficient, a part of the defect may not be corrected and remains as a remaining defect. In the following description, when “defects” are simply described, residual defects are not included unless otherwise specified. In addition, when comparing the defect corresponding to each other and the remaining defect, the defect may be expressed as a “first defect”.

  Hereinafter, for convenience of explanation, the surface of the glass substrate 2 on which the circuit pattern is formed is rectangular, and the direction of the long side of the rectangle is the x axis and the direction of the short side is the y axis. The direction perpendicular to the surface of the glass substrate 2, that is, the height direction of the glass substrate 2, is defined as the z-axis.

  The laser repair apparatus 101 has a function of moving a relative position between the glass substrate 2 and the objective lens 9 in the x direction and the y direction. That is, the relative position of the glass substrate 2 and the imaging optical system can be moved in the x direction and the y direction, and the relative position of the glass substrate 2 and the laser irradiation optical system can also be moved in the x direction and the y direction. . The movement of the relative position is realized as follows in the first embodiment.

  The stage 1 includes a motor or an actuator for moving the stage 1 in the x direction and the y direction, and the laser repair apparatus 101 includes a movement / drive control unit 3. Further, the imaging optical system and the laser irradiation optical system are in positions fixed with respect to the floor. The movement / drive control unit 3 instructs the stage 1 to move in the x and y directions, and controls the position of the stage 1 in the x and y directions. Therefore, the relative position of the glass substrate 2 with respect to the objective lens 9 can be arbitrarily moved in the x direction and the y direction.

  In the first embodiment, the substrate inspection apparatus 4 that is an external apparatus of the laser repair apparatus 101 is connected to the laser repair apparatus 101 via a network or directly. The substrate inspection device 4 images the glass substrate 2 with a line sensor, for example, and inspects the glass substrate 2 based on the captured image to detect the position of the defect. The movement / drive control unit 3 receives defect position data regarding the position of the detected defect from the substrate inspection apparatus 4, calculates the movement amount of the stage 1 in the x direction and the y direction based on the received defect position data, Control stage 1.

  As a result, the glass substrate 2 moves relative to the objective lens 9 in the x direction and the y direction. Here, since the influence of the error can be ignored by applying the error correction method in the relative movement, the following description will be made ignoring the error in the relative movement. Then, as a result of the relative movement in the x direction and the y direction, the stage 1 has the optical axis of the objective lens 9 parallel to the z axis at a defect position on the glass substrate 2 detected by the substrate inspection apparatus 4. That is, the defect detected by the substrate inspection apparatus 4 is located at the center of the field of view of the imaging optical system and at the irradiation position of the laser beam by the laser irradiation optical system.

  In other embodiments, the relative movement between the glass substrate 2 and the objective lens 9 may be performed by other methods. For example, the laser repair apparatus 101 includes a gantry having a beam along the y direction, the imaging optical system and the laser irradiation optical system move in the y direction along the beam of the gantry, and the stage 1 moves in the x direction. Relative movement may be performed. Also in this case, the movement / drive control unit 3 controls the relative movement in the x direction and the y direction.

  Next, components related to imaging of defects in the laser repair apparatus 101 will be described. The imaging optical system included in the laser repair device 101 includes an illumination light source 5, a relay lens 6, a beam splitter 7, a beam splitter 8, an objective lens 9, an imaging lens 10, and an imaging unit 11. Image data captured by the imaging unit 11 is sent to the image processing unit 12 for processing and displayed on the monitor 13.

  The illumination light source 5 emits illumination light necessary for imaging the glass substrate 2. The relay lens 6, the beam splitter 7, the beam splitter 8, and the objective lens 9 are disposed on the optical path where the illumination light reaches the glass substrate 2. That is, the illumination light emitted from the illumination light source 5 and reaching the beam splitter 7 via the relay lens 6 is reflected by the beam splitter 7, passes through the beam splitter 8, and passes on the glass substrate 2 via the objective lens 9. Irradiated.

  The reflected light from the glass substrate 2 passes through the beam splitter 8 and the beam splitter 7 through the objective lens 9 and then forms an image on the light receiving element of the imaging unit 11 by the imaging lens 10. Imaging is performed.

  The imaging unit 11 is realized by, for example, a charge coupled device (CCD) image sensor or a complementary metal-oxide semiconductor (CMOS) image sensor. In the following, for simplification of description, the imaging unit 11 is described on the assumption that a monochrome luminance image is captured. However, the imaging unit 11 may be an image sensor that captures a color image. Note that the imaging optical system is configured such that the light receiving element of the imaging unit 11 is positioned conjugate to the surface of the glass substrate 2.

  The imaging unit 11 outputs the captured image of the glass substrate 2 to the image processing unit 12. The image processing unit 12 performs various processes described later on the input image, thereby detecting a defect on the image captured by the imaging unit 11 and recognizing an accurate position and range of the defect. Further, the image processing unit 12 outputs an image captured by the imaging unit 11 and an image generated as a result of processing by the image processing unit 12 to the monitor 13. The inspector can visually confirm various images output to the monitor 13.

Similar to the defect, the remaining defect can be imaged by the imaging optical system, but the imaging unit 11 does not need to image the remaining defect unless confirmation by an inspector is particularly required.
Next, components related to the correction of defects and residual defects in the laser repair apparatus 101 will be described. The laser irradiation optical system provided in the laser repair device 101 includes a laser oscillator 14, a beam splitter 15, a mirror 16, a DMD (Digital Micromirror Device) unit 17, a relay lens 18, a beam splitter 8, and an objective lens 9.

  In addition, the laser repair device 101 projects light onto the glass substrate 2 for the purpose of correcting the error of the laser light irradiation position before actually irradiating the glass substrate 2 with laser light for correcting defects or residual defects. To do. The laser irradiation optical system further includes a repair position confirmation light source 21 for this purpose. The repair position confirmation light source 21 is, for example, an LED (Light Emitting Diode) light source. The light from the LED light source does not cause physical influences such as removal of defects and generation of burnt eyes even when the glass substrate 2 is irradiated.

  The DMD unit 17 is driven by a driver 20, and the driver 20 is controlled by a laser shape controller 19. In other words, the laser shape controller 19 and the driver 20 function as modulation control means for controlling the DMD unit 17 as two-dimensional spatial light modulation means. The control by the laser shape control unit 19 is based on the image processed by the image processing unit 12.

  The laser oscillator 14 emits a laser beam for correcting a defect or a remaining defect on the glass substrate 2. The beam splitter 15, the mirror 16, the DMD unit 17, the relay lens 18, the beam splitter 8, and the objective lens 9 are arranged on the optical path where the laser light reaches the glass substrate 2.

The laser light emitted from the laser oscillator 14 passes through the beam splitter 15, is reflected by the mirror 16, and enters the DMD unit 17 at a predetermined angle θ _in . The DMD unit 17 is one type of two-dimensional spatial light modulator that controls the light irradiation shape to an arbitrary shape, and other types of two-dimensional spatial light modulators using transmissive liquid crystal or reflective liquid crystal are DMD. It can be used instead of the unit 17. Further, in order to irradiate light only at a desired position and range, in addition to the two-dimensional spatial light modulator, a slit capable of changing the size of the opening can be used.

  The DMD unit 17 is a device in which a plurality of micromirrors are arranged in a two-dimensional array. Each of the micromirrors is driven at a different inclination angle of the mirror surface according to the state of each corresponding memory cell for driving. There are “on state” and “off state” in the state of the memory cell, and the driver 20 drives each micromirror independently to either the on state or the off state by driving the memory cell.

Incident light that is incident on the minute mirror in the on state at the predetermined angle θ _in is reflected by the DMD unit 17 at the predetermined angle θ _out . However, in the ON state and the OFF state, the inclination angle of the mirror surface of the micro mirror is different, the incident light incident at the same predetermined angle theta _in respect micromirrors in the OFF state is different from the predetermined angle theta _out Reflects in the direction. For example, the difference in tilt angle of the micromirror between the on state and the off state is 10 degrees.

DMD unit 17, the laser beam reflected by the mirror 16 is arranged to be incident at a predetermined angle theta _in. Then, the laser light reflected by the micro mirror in the on state at a predetermined angle θ _out is parallel to the optical axis of the relay lens 18, and the laser light reflected by the micro mirror in the off state is relayed. A relay lens 18 is arranged so as not to enter the lens 18. The laser irradiation optical system is configured so that the surface of the glass substrate 2 and the DMD unit 17 are in a conjugate position.

  Therefore, only the laser light reflected by the micro mirror in the on state reaches the beam splitter 8 via the relay lens 18, is reflected by the beam splitter 8, is condensed by the objective lens 9, and is irradiated onto the glass substrate 2. The

  The light emitted from the repair position confirmation light source 21 is reflected by the beam splitter 15, and after being reflected by the beam splitter 15, the light is emitted onto the glass substrate 2 by the same optical path as the laser light emitted from the laser oscillator 14. Projected. Accordingly, the repair position confirmation light source 21 emits light in a state where the DMD unit 17 drives each micromirror according to a specific pattern, so that the irradiation range of the laser light according to the specific pattern is increased. It can be confirmed whether or not it matches the desired range.

  That is, confirmation is performed as follows. The laser oscillator 14 does not emit laser light, and the repair position confirmation light source 21 emits light. The light from the repair position confirmation light source 21 is spatially light modulated by the DMD unit 17 by the specific pattern and projected onto the glass substrate 2. Thus, the imaging unit 11 images the glass substrate 2 onto which the light of the specific pattern is projected.

  Then, in the captured image, the image processing unit 12 determines whether the defect to be corrected or the range of the remaining defect matches the range of the light projected from the repair position confirmation light source 21. When the image processing unit 12 detects a mismatch between the two ranges, the image processing unit 12 controls the laser shape control unit 19 to correct the pattern instructed to the driver 20 and eliminate the mismatch. Note that the cause of the mismatch is, for example, a deviation in the mounting angle of components in the laser repair device 101.

  The repair position confirmation light source 21 and the beam splitter 15 can be omitted by using the laser oscillator 14 whose output level can be adjusted. By irradiating a low-level laser beam on a range to be irradiated with a high-level laser beam for correction, the irradiation range can be confirmed without causing a physical influence on the glass substrate 2.

  As described above, the imaging unit 11 captures the defect on the glass substrate 2 detected by the substrate inspection apparatus 4, and the image processing unit 12 detects the defect based on the image and determines the accurate position and range of the defect. recognize. That is, in the first embodiment, the imaging unit 11 and the image processing unit 12 function as defect detection means.

  The laser repair device 101 performs confirmation using the repair position confirmation light source 21 based on the position and range recognized by the image processing unit 12, and then corrects the position and range of the glass substrate 2 to be corrected. Then, a laser beam is irradiated from the laser oscillator 14 to correct the defect. By the relative movement by the stage 1 and the spatial light modulation by the DMD unit 17, the laser repair apparatus 101 can irradiate the laser beam from the laser oscillator 14 to an arbitrary range on the glass substrate 2.

  Further, the laser repair apparatus 101 determines whether or not there is a remaining defect by the remaining defect detection unit 22 and, if there is a remaining defect, corrects the remaining defect in the same manner as the defect correction.

  Here, the remaining defect detection unit 22 acquires height information regarding the height of the glass substrate 2 and determines whether or not there is a remaining defect based on the height information. The method of acquiring the height information and the hardware configuration for realizing the remaining defect detection unit 22 vary depending on the embodiment, and specific examples will be described in detail in the second embodiment and later.

  The reason for using the height information is that, as described above, when the glass substrate 2 is burnt due to the first defect correction, it may be difficult to distinguish the burnt and the remaining defect from the appearance, but the height information is used. This is because it is possible to easily discriminate between burnt eyes and remaining defects. This is because although there is no height in the burnt eye, the remaining defect is a substance to be removed, so that the remaining defect has a height. The height information may be information indicating the specific height of each point on the glass substrate 2, but only information indicating whether or not a convex portion having a height exists in the first defect range. But you can. This is because if only the presence / absence of a convex portion having a height is shown, it is possible to distinguish between a case in which there is no residual defect and only a burnt eye and a case in which a residual defect actually exists.

  Further, when there is a remaining defect, the position and range of the remaining defect are limited to a part or all of the range of the first defect from the definition of the remaining defect. Therefore, the remaining defect detection unit 22 may limit the range on the glass substrate 2 from which height information should be acquired in order to detect the remaining defect based on the defect range detected by the image processing unit 12. . Due to such a limitation, the remaining defect detector 22 can efficiently detect the remaining defects.

  Further, the remaining defect detection unit 22 may only determine the presence or absence of a remaining defect, and may further perform processing for recognizing the position and range of the remaining defect. Depending on the nature of the defect to be corrected and the nature of the previous process, no problem occurs even if the residual defect detector 22 does not recognize the position and range of the residual defect. In other words, since the range of the remaining defects is not wider than the range of the first defects, if the laser beam is irradiated to the same range as the first defect, the laser beam is always irradiated to the remaining defects. Therefore, the laser repair apparatus 101 can also correct the remaining defect by irradiating the same range as the first defect with the laser beam.

  In the first embodiment, the residual defect detection unit 22 detects the residual defect after laser irradiation of the defect. As will be described later with reference to FIG. 14, the residual defect detection unit 22 determines whether or not there is a residual defect. The timing determined by 22 may be before the laser irradiation of the defect. That is, the remaining defect detection unit 22 may predict whether or not there is a remaining defect after the laser irradiation to the defect based on the height information before the laser irradiation to the defect. In this case, determining the presence or absence of a residual defect means predicting the presence or absence of a residual defect in the future.

As described above, the specific configuration and operation of the remaining defect detection unit 22 can be variously changed. However, when the remaining defect detection unit 22 detects the remaining defect, the remaining defect is corrected as follows.
The remaining defect detection unit 22 notifies the image processing unit 12 whether or not a remaining defect has been detected. Further, when the remaining defect detection unit 22 also recognizes the position and range of the remaining defect, it notifies the image processing unit 12 of the recognized position and range. When notified that the remaining defect has been detected, the image processing unit 12 generates data necessary for the laser shape control unit 19 to instruct the driver 20 of the range to be irradiated with the laser beam for correcting the remaining defect. To the laser shape controller 19.

  Specifically, when the residual defect detection unit 22 notifies the image processing unit 12 of the recognition result of the position and range of the residual defect, the image processing unit 12 displays data indicating the notified position and range as a laser shape. Output to the control unit 19. When the remaining defect detection unit 22 only detects the remaining defect, the image processing unit 12 performs laser shape control on the same data as when the first defect is corrected, that is, data indicating the position and range of the first defect. To the unit 19.

As a result, similarly to the defect correction, the laser beam from the laser oscillator 14 is spatially modulated and irradiated to a range including at least the remaining defect, so that the remaining defect is corrected.
The detection and correction of the remaining defects may be performed only once. However, in the first embodiment, for each defect, the laser repair apparatus 101 repeatedly detects and corrects the remaining defects until no remaining defects are detected.

  In the above description, “notification” from the remaining defect detection unit 22 to the image processing unit 12 is described. For example, in the second embodiment described later, the image processing unit 12 is a part of the remaining defect detection unit 22. Also works, so there may be no explicit notification.

  The configuration of the laser repair device 101 has been described above, but the laser repair device 101 may further include a timing control unit (not shown) that controls the operation timing of each of the above-described components.

  For example, the timing control unit instructs the lighting and extinguishing timings of the illumination light source 5, the laser oscillator 14, and the repair position confirmation light source 21, instructs the imaging unit 11 about the imaging timing, and instructs the remaining defect detection unit 22. The timing for detecting the remaining defect is instructed. The timing control unit may further control the operation timing of other components. For example, the movement / drive control unit 3 may notify the timing control unit that the relative movement has been completed, and the image processing unit 12 may notify the completion of the image processing.

  Further, at least a part of the timing control unit (not shown), the movement / drive control unit 3, the image processing unit 12, the laser shape control unit 19, and the remaining defect detection unit 22 is a general purpose such as a PC (Personal Computer) or a workstation. It can be realized by a typical computer.

  That is, the laser repair device 101 may incorporate a PC that functions as a control device for the laser repair device 101. Alternatively, the laser repair device 101 itself does not include a timing control unit (not shown), the movement / drive control unit 3, the image processing unit 12, the laser shape control unit 19, and the remaining defect detection unit 22. A part not included in the apparatus 101 may be realized by an external PC that functions as a control apparatus of the laser repair apparatus 101. An external PC is connected to the laser repair device 101 directly or via a network, and controls the laser repair device 101.

  A PC built in the laser repair device 101 or a PC outside the laser repair device 101 includes a CPU (Central Processing Unit), a nonvolatile memory such as a ROM (Read Only Memory), and a RAM (Random) used as a working area. Access Memory), an external storage device such as a hard disk device, and a connection interface with an external device. And each component of PC is mutually connected by the bus | bath. A monitor 13 is connected to the PC.

  The PC further includes an input device including a pointing device such as a mouse and a keyboard for receiving input from an inspector who is a user, an output device such as a printer, and a drive device for a computer-readable portable storage medium. Good.

  When the CPU reads a program stored in a ROM, a hard disk device, a portable storage medium, or the like or a program provided via a network into the RAM and executes the program, the PC performs a timing control unit (not shown), At least some functions of the drive control unit 3, the image processing unit 12, the laser shape control unit 19, and the remaining defect detection unit 22 can be realized.

  In the embodiment in which the PC realizes the functions of these units, the following is used as the connection interface. For example, in order to realize the image processing unit 12, an image capture board is used as an interface with the imaging unit 11. Similarly, an interface with the driver 20 may be used to realize the laser shape control unit 19, and an interface with the motor or actuator of the stage 1 to realize the movement / drive control unit 3. May be used.

  Of course, the timing control unit, the movement / drive control unit 3, the image processing unit 12, the laser shape control unit 19, and the remaining defect detection unit 22 (not shown) can be realized by dedicated hardware.

  The details of the configuration and operation of the laser repair apparatus 101 according to the first embodiment have been described above. Next, details of the operation of the laser repair apparatus 101 will be described along the flow with reference to FIG.

  FIG. 2 is a flowchart showing the operation of the laser repair apparatus 101 in the first embodiment. A series of processes in FIG. 2 are processes related to one glass substrate 2. FIG. 3 is a diagram illustrating an example of an image used for defect detection in the first embodiment.

  In step S <b> 101, the glass substrate 2 is carried into the laser repair apparatus 101 and placed at a predetermined position on the stage 1. Further, defect position data related to the glass substrate 2 is transmitted from the substrate inspection apparatus 4 to the movement / drive control unit 3. The defect position data includes information on the positions of N defects (N is an integer of 1 or more) detected by the substrate inspection apparatus 4.

  Therefore, in step S101, the movement / drive control unit 3 further selects one unprocessed defect among the N defects and reads defect position data related to the selected defect. The movement / drive control unit 3 controls the relative movement of the stage 1 based on the read data by the method described with reference to FIG.

As a result of the relative movement, the imaging optical system and the laser irradiation optical system of the laser repair apparatus 101 move to the position of the defect selected by the movement / drive control unit 3.
Subsequently, in step S <b> 102, the imaging unit 11 images the glass substrate 2 and outputs an image signal to the image processing unit 12. Thereby, the image processing unit 12 acquires, for example, data of the defect image Da in FIG. The defect image Da includes a defect portion G that straddles the two circuit patterns C1 and C2. The “defect portion” refers to a portion corresponding to a defect in the image.

In the next step S103, the image processing unit 12 extracts a defect to be corrected as follows.
That is, the image processing unit 12 acquires the reference image Db having no defect portion illustrated in FIG. 3, and compares the captured defect image Da with the acquired reference image Db. That is, the image processing unit 12 calculates a difference in luminance between the defect image Da and the reference image Db for each pixel, and generates a difference image Dc shown in FIG.

  For example, when the luminance representing black is 0 and the luminance representing white is 255, the image processing unit 12 subtracts the absolute value of the luminance difference between the defect image Da and the reference image Db from 255 for each pixel. The luminance in the difference image Dc may be calculated. The image processing unit 12 may generate the difference image Dc by another method.

  In general, the same circuit pattern is repeated in a two-dimensional array on the glass substrate 2 of the FPD. Here, for the sake of convenience, the repeating unit is referred to as a “unit pattern”. The imaging unit 11 or other device captures in advance a unit pattern that has already been determined not to contain a defect, and stores the captured image in a storage device included in the laser repair device 101. Thereby, the image processing unit 12 can acquire the reference image Db for the defect detected at any position.

  In step S103, the image processing unit 12 further performs a binarization process on the difference image Dc to generate a binarized defect shape image Dd. The image processing unit 12 uses, for example, a predetermined threshold value or determines a threshold value from the luminance distribution in the difference image Dc, and compares the luminance of each pixel of the difference image Dc with the threshold value to Perform value processing.

  As a result of the binarization processing, a portion having a large luminance difference from the reference image Db in the defect image Da is extracted as a defect portion G in the defect shape image Dd. That is, the image processing unit 12 recognizes the defect and recognizes the position and range of the defect on the glass substrate 2 corresponding to the defect part G of the defect shape image Dd through a series of processes in step S103.

  In the example of FIG. 3, in the defect shape image Dd, the defect portion G is represented in black and the background region is represented in white. As will be described in detail later, the defect shape image Dd is used for controlling the DMD unit 17. Therefore, in the first embodiment, each pixel included in the defect portion G of the defect shape image Dd is represented by a value “1” corresponding to the ON state of the micromirror of the DMD unit 17. On the other hand, each pixel included in the background region of the defect shape image Dd, that is, the region other than the defect portion G, is represented by a value “0” corresponding to the off state of the micromirror. That is, it should be noted that the value “1” or “0” representing each pixel in the defect shape image Dd is not a value indicating the luminance itself but a value for controlling the DMD unit 17.

  When the image processor 12 extracts the defect portion G by generating the defect shape image Dd as described above, the image processor 12 further outputs the data of the defect shape image Dd to the laser shape controller 19 in step S103. At the same time, the defect image Da, the difference image Dc, and the defect shape image Dd are output to the monitor 13. This is because the output to the monitor 13 enables visual confirmation by the inspector.

  Depending on the embodiment, the image output from the image processing unit 12 to the monitor 13 is arbitrary. For example, the image processing unit 12 generates an image in which the range extracted as the defect portion G in the defect shape image Dd is expressed in a specific color and overlaps the defect image Da, and the generated image is output to the monitor 13. May be. Alternatively, if confirmation by an inspector is unnecessary, the monitor 13 may not display an image.

  Subsequent to step S <b> 103, in step S <b> 104, the laser shape control unit 19 converts the defect shape image Dd data received from the image processing unit 12 into a control signal for controlling the driver 20. That is, the laser shape control unit 19 turns on the micromirror driving memory cell of the DMD unit 17 corresponding to the region of the defective portion G, and the memory cell corresponding to the background region other than the defective portion G. Is sent to the driver 20 for turning off the.

  Note that one pixel in the defect shape image Dd corresponds to one minute mirror in the DMD unit 17 by appropriately selecting the magnification of each lens, the specification of the imaging unit 11, and the specification of the DMD unit 17 in the laser repair device 101. Thus, the laser repair device 101 can be configured. In this case, the laser shape control unit 19 drives the minute mirror corresponding to the pixel having the value “1” meaning that it belongs to the defect part G in the data of the received defect shape image Dd, and the background A control signal for driving the micromirror corresponding to the pixel having the value “0” that belongs to the region to the OFF state is output to the driver 20.

  Depending on the embodiment, the pixel and the micromirror may not correspond one-to-one. In that case, the laser shape control unit 19 first specifies one or more pixels of the corresponding defect shape image Dd for each micro mirror of the DMD unit 17. Then, the laser shape control unit 19 determines whether the micromirror should be driven on or off based on the value of one or more specified pixels, that is, a value of “0” or “1”. The control signal according to the determination result is output to the driver 20.

  Further, in step S104, the driver 20 that has received the control signal from the laser shape controller 19 drives each memory cell of the DMD unit 17 to the on state or the off state in accordance with the control signal. That is, the driver 20 drives each micromirror in an on state or an off state in accordance with the control signal.

  Subsequently, in step S105, the irradiation range is confirmed using the repair position confirmation light source 21 as described above. After the image processing unit 12 confirms that the DMD unit 17 is appropriately driven so that the laser beam is accurately irradiated to the range to be irradiated with the laser beam, that is, the detected defect range, the laser oscillator 14 Irradiates one shot of laser light.

The laser light emitted from the laser oscillator 14 passes through the beam splitter 15, is reflected by the mirror 16, and enters the DMD unit 17 at a predetermined angle θ _in . The micro mirror in the on state reflects in the direction of the optical path to the beam splitter 8 via the relay lens 18, and the micro mirror in the off state reflects in a direction different from the relay lens 18.

  As a result, the cross-sectional shape of the laser light beam reflected by the DMD unit 17 and applied to the glass substrate 2 via the relay lens 18, the beam splitter 8, and the objective lens 9 is extracted as a defect portion G by the defect shape image Dd. Match the shape of the defect made. Therefore, the defect on the glass substrate 2 corresponding to the defect part G is removed and corrected by the laser beam.

  However, in reality, there are cases where defects cannot be completely removed, that is, repair is not complete. Therefore, it is necessary to determine whether repair is necessary. Therefore, in step S106, the residual defect detection unit 22 performs a process of detecting a residual defect. That is, the remaining defect detection unit 22 determines whether there is a portion that needs to be further corrected, which remains because the defect correction in step S105 is insufficient. That is, the remaining defect detection unit 22 acquires the height information of the glass substrate 2 and determines whether there is a remaining defect based on the acquired height information.

In step S106, the remaining defect detection unit 22 may further perform processing for recognizing the position and range of the remaining defect.
In the first embodiment, when there is a residual defect, the residual defect detection unit 22 determines that the residual defect needs to be corrected, but the residual defect detection unit determines whether the residual defect needs to be corrected. 22 may further determine. Whether correction is necessary depends on the position, range, or shape of the remaining defect.

  By the way, conventionally, for the remaining defect, the image pickup unit 11 picks up the corrected glass substrate 2 and outputs the image to the image processing unit 12, and the image input by the image processing unit 12 and the reference image Db in FIG. In comparison, a difference image is generated by the same method as in step S103, and the region corresponding to the remaining defect is extracted. However, with this conventional method, as described above, it is difficult to accurately distinguish between burnt marks and remaining defects. For this reason, conventionally, it has been necessary to introduce the necessity of re-correction by visual inspection by an inspector, and it has been difficult to fully automate the laser repair device.

Therefore, in the first embodiment, the remaining defect detection unit 22 uses height information in order to easily distinguish between burnt marks and remaining defects.
When the laser beam emitted from the laser oscillator 14 is strong, the glass substrate 2 may be burnt. The burnout may occur on the surface of the glass substrate 2 after the defect is completely removed. Alternatively, when a part of the initial defect remains as a remaining defect, a burn may occur across the surface of the glass substrate 2 where the defect has been removed and the surface of the remaining defect. Therefore, whether or not a burn has occurred, and whether or not the range of the burn and the remaining defect overlap, varies depending on the case.

  However, if the height information is used, it is possible to clearly distinguish a residual defect which is a convex part having a height on the glass substrate 2 and a burnt mark on the surface of the glass substrate 2 where no residual defect remains. It is.

  Subsequent to step S106, in step S107, the remaining defect detection unit 22 determines whether re-correction is necessary. Basically, whether or not re-correction is necessary is determined by whether or not a remaining defect is detected. However, in the first embodiment, in order to prevent excessive irradiation of the laser beam, in step S107, the remaining defect detection unit 22 specifically determines in the first to third cases as follows. I do.

  The first case is a case where no remaining defect is detected in step S106. In the first case, the remaining defect detection unit 22 determines that re-correction is unnecessary, and the process proceeds to step S108.

  On the other hand, if a remaining defect is detected in step S106, this is the second or third case. When a remaining defect is detected in step S106, the remaining defect detection unit 22 determines whether or not a predetermined number (M times) of laser irradiation has already been performed on the currently focused defect.

  The second case is a case where M times of laser irradiation have already been performed. In the second case, in order to prevent excessive laser irradiation, the remaining defect detection unit 22 determines that re-correction is unnecessary, and the process proceeds to step S108.

  The third case is a case where the laser irradiation has been performed to the defect currently focused on less than M times so far. In the third case, the remaining defect detector 22 determines that recorrection of the remaining defect detected in step S106 is necessary. In the third case, the remaining defect detection unit 22 notifies the image processing unit 12 that recorrection is necessary. If the remaining defect detection unit 22 recognizes the position and range of the remaining defect in step S106, the remaining defect detection unit 22 further notifies the image processing unit 12 of the recognition result. In the third case, the image processing unit 12 that receives the notification from the remaining defect detection unit 22 operates as follows.

  That is, if the recognition result of the position and range of the remaining defect is also received, the image processing unit 12 determines the region of the remaining defect in the same format as the defect shape image Dd in FIG. The generated image data is generated, and the generated image data is output to the laser shape controller 19. Alternatively, if the recognition result of the position and range of the remaining defect has not been received, the image processing unit 12 outputs the data of the defect shape image Dd to the laser shape control unit 19 again with a notification that the remaining defect has been detected. .

Thus, in the third case, the processing by the image processing unit 12 is performed, and then the processing returns to step S104.
Accordingly, the processes in steps S104 to S107 are repeated until no remaining defect is detected or M times of laser irradiation, which is the specified number of times, are performed. Steps S104 and S105 in the first repetition are steps for defect correction, and steps S104 and S105 in the second and subsequent steps are steps for remaining defects.

  When the process proceeds from step S107 to step S108, the movement / drive control unit 3 determines whether there are other unprocessed defects among the N defects corresponding to the defect position data received from the substrate inspection apparatus 4. Determine. If there are no other unprocessed defects, all the corrections related to the glass substrate 2 have been completed, and the processing of FIG. 2 ends. If there are other unprocessed defects, the process returns to step S101. Thus, Steps S101 to S108 are executed for each of the N defects.

Since the first embodiment has been described above, other embodiments in which the remaining defect detection unit 22 in the first embodiment is variously modified will be described in order below.
The second embodiment is an embodiment in which a residual defect having a height is detected using a shadow formed by irradiating light from an oblique direction. Hereinafter, the second embodiment will be described with reference to FIGS. 4 and 5.

FIG. 4 is a configuration diagram of the laser repair apparatus 102 according to the second embodiment. The difference between the laser repair apparatus 101 in FIG. 1 and the laser repair apparatus 102 in FIG. 4 is as follows.
That is, the laser repair apparatus 102 further includes an illumination light source 23 and a relay lens 24 for irradiating illumination light obliquely with respect to the surface of the glass substrate 2. The image processing unit 12 b in the laser repair apparatus 102 also functions as a part of the residual defect detection unit 22 in the laser repair apparatus 101 in addition to the same function as the image processing unit 12 in the laser repair apparatus 101. Therefore, the imaging unit 11 not only captures an image similar to that in the first embodiment, but also captures an image used by the image processing unit 12b to detect a residual defect. That is, in the second embodiment, the function of the remaining defect detection unit 22 of the first embodiment is realized by the imaging unit 11, the image processing unit 12b, the illumination light source 23, and the relay lens 24.

The angle φ ₁ formed by the optical axis of the illumination light irradiated onto the glass substrate 2 from the illumination light source 23 via the relay lens 24 with the surface of the glass substrate 2, that is, the angle φ ₁ formed by the optical axis of the illumination light with the xy plane is: For example, the angle is 30 degrees or less, and more preferably, the angle is 10 degrees or less so that the irradiation is performed almost from the side.

  The operation of the laser repair apparatus 102 configured as described above is the same as that of the flowchart of FIG. 2, but the operation of step S106 is more concrete in the second embodiment. Therefore, in the following, details of the operation of the laser repair apparatus 102 in step S106 will be described with reference to FIG.

In step S106, the illumination light source 5 is turned off and the illumination light source 23 is turned on in order to increase the detection accuracy of the remaining defects. The illumination light source 23 emits illumination light from the oblique angle φ _{1 with} respect to the glass substrate 2 toward the center of the field of view of the imaging optical system, that is, toward the position of the first defect extracted as the defect portion G in step S103. Irradiate.

  The illumination light emitted from the illumination light source 23 illuminates a flat area on the surface of the glass substrate 2. However, since the illumination light is blocked at the convex portion having a height on the glass substrate 2, a shadow is created on the opposite side to the illumination light source 23.

  Here, for simplification of the description, it is assumed that the surface of the glass substrate 2 should be flat if there is no defect or residual defect in the current process, which is a target for detecting and correcting the defect. Then, the creation of a shadow in step S <b> 106 means that there is a residual defect having a height higher than the surroundings on the surface of the glass substrate 2 that should originally be flat.

  In other words, in the second embodiment, the height information includes information indicating “there is a residual defect having a height because there is a shadow” or information indicating “no residual defect because there is no shadow”. .

  Therefore, in step S106 of the second embodiment, the imaging unit 11 images the glass substrate 2 in the same manner as in step S102 in a situation where the illumination light from the illumination light source 23 illuminates the glass substrate 2, and the captured image The data is output to the image processing unit 12b. The image processing unit 12b determines the presence or absence of a residual defect by determining the presence or absence of a shadow based on the received data. An example of residual defect detection by the image processing unit 12b will be described below with reference to FIG.

FIG. 5 is a diagram illustrating an example of an image used for detection of a remaining defect in the second embodiment.
The remaining defect image De in FIG. 5 is an example of an image captured by the imaging unit 11 in step S106. The residual defect image De is similar to the defect image Da of FIG. 3, but includes a residual defect portion Gb corresponding to the residual defect instead of the defect portion G corresponding to the first defect, and a shadow caused by the residual defect is reflected. It differs in that it includes the shadow H.

  Therefore, similarly to the case where the difference image Dc is generated in step S103 of FIG. 2, the image processing unit 12b compares the remaining defect image De and the reference image Db of FIG. 3, and generates the difference image Df of FIG. . The image processing unit 12b further performs binarization processing on the difference image Df to generate a binarized shadow shape image Dg. Since the binarization process for generating the shadow shape image Dg is similar to the binarization process for generating the defect shape image Dd from the difference image Dc in step S103, detailed description thereof is omitted.

  In FIG. 5, the shadow H in the shadow shape image Dg is shown in black, and the background area other than the shadow H is shown in white. Similar to the defect shape image Dd in FIG. 3, in the shadow shape image Dg, the luminance of each pixel included in the black shadow portion H is represented by a value of “1”, and the luminance of each pixel included in the white background region is It is represented by the value “0”. Through the series of processes described above, the image processing unit 12b extracts the shadow portion H.

  If an appropriate illumination light source 23 is used, the luminance in the residual defect image De of the shadow portion H becomes lower than the luminance in the residual defect portion Gb. Therefore, when the difference in luminance between the remaining defect portion Gb and the shadow portion H is used, the image processing unit 12b includes the remaining defect portion Gb in the background region by performing binarization processing using an appropriate threshold value. Such a shadow shape image Dg can be generated. That is, the image processing unit 12b can extract only the shadow portion H by using an appropriate threshold value.

  An appropriate threshold value for extracting the shadow portion H may be an appropriate value obtained by conducting an experiment in advance. Alternatively, in the case of a glass substrate 2 of a type in which the luminance of the residual defect portion Gb and the shadow portion H in the difference image Df is greatly different, even if the image processing unit 12b dynamically determines the threshold value from the luminance distribution in the difference image Df. Good.

  In any case, in step S106, the image processing unit 12b performs a process of extracting the shadow portion H. If the shadow portion H exists, the image processing portion 12b determines that there is a convex portion having a height, that is, a residual defect, and the shadow portion H exists. Otherwise, it is determined that there are no remaining defects. In order to suppress the influence of noise, the image processing unit 12b determines that the shadow part H exists only when the area of the shadow part H in the shadow shape image Dg is equal to or larger than a predetermined size.

  Then, instead of the remaining defect detection unit 22 in FIG. 1, the image processing unit 12 b performs the determination in step S <b> 107 in the same manner as the remaining defect detection unit 22. The subsequent processing is the same as in FIG. 2 of the first embodiment.

Although the second embodiment has been described above, the second embodiment can be variously modified, and the modified examples described below are examples thereof.
Irradiation angle phi ₁ of the illumination light from the illumination source 23 shown in FIG. 4 may be variously modified. For example, in a certain kind of glass substrate 2, the average height of the remaining defects is several tens of nm. Therefore, the irradiation angle φ ₁ is set to a small value so that a shadow created by a residual defect with a height of several tens of nm can be extracted as the shadow portion H, that is, so that the shadow becomes as long as possible. It is desirable. That is, the upper limit of a value suitable as the irradiation angle φ ₁ also changes according to the resolution of the imaging optical system.

  In the second embodiment, since the process of recognizing the exact position and range of the remaining defect is not performed, the range irradiated with the laser beam for correcting the remaining defect is the range of the first defect. The same. However, it is possible to modify the second embodiment so that the image processing unit 12b further performs a process of recognizing the range or height of the remaining defect from the size of the extracted shadow H.

For example, the image processing unit 12b may calculate the height of the residual defect based on the irradiation angle phi ₁ of the illumination light from the shadow H length and illumination light source 23. The image processing unit 12b may control the laser oscillator 14 so that the higher the calculated remaining defect is, the higher the output power is.

  Further, the image processing unit 12b may perform processing for narrowing down the position and range of the remaining defect based on the direction of the optical axis of the illumination light from the illumination light source 23 and the shape and range of the shadow H. In this case, the image processing unit 12b may generate image data representing the narrowed range in the same format as the shadow shape image Dg and output the data to the laser shape control unit 19. Thereby, excessive laser irradiation can also be prevented.

  Further, the process for extracting the shadow portion H is not limited to the above procedure. For example, in step S106, the imaging unit 11 may further capture a second remaining defect image (not shown) in addition to the remaining defect image De. The second remaining defect image is captured in a situation where the illumination light source 5 is turned on and the illumination light source 23 is turned off, as in step S102 of FIG. Since the obtained second remaining defect image includes the remaining defect portion Gb, the image processing unit 12b generates a difference image between the second remaining defect image (not shown) and the remaining defect image De in FIG. May be. If an appropriate type of illumination light source 5 and illumination light source 23 are selected, the image processing unit 12b can also obtain the shadow shape image Dg shown in FIG. A similar image can be acquired and the presence or absence of the shadow H can be detected.

  In the above description, it is assumed that the surface of the glass substrate 2 should be flat if there are no defects or residual defects. However, the second embodiment can be modified so as to be able to cope with the case where there are irregularities due to a normally formed circuit pattern.

  That is, the illumination light source 23 irradiates the illumination light to the portion of the unit pattern that has been previously found to be free of defects, which was used to capture the reference image Db in FIG. And the imaging part 11 images the unit pattern on a glass substrate in the state. The captured image is hereinafter referred to as a “shadowed reference image” for convenience. The shadowed reference image shows a shadow generated according to the irregularities of the normal circuit pattern. The shaded reference image is captured in advance and stored in a storage device (not shown) included in the laser repair device 102.

  Therefore, the image processing unit 12b uses the shaded reference image instead of the reference image Db in FIG. 3 to generate the difference image Df from the remaining defect image De and the shaded reference image in FIG. The shadow portion H can be extracted in the same manner as in the second embodiment.

The second embodiment and the modifications thereof have been described above. Next, a third embodiment will be described.
The third embodiment is an embodiment in which projection light having a predetermined pattern is projected onto a substrate, and a residual defect having a height is detected from distortion of the projection light on the substrate. Hereinafter, the third embodiment will be described with reference to FIGS.

FIG. 6 is a configuration diagram of the laser repair apparatus 103 according to the third embodiment. The difference between the laser repair apparatus 101 of FIG. 1 and the laser repair apparatus 103 of FIG. 6 is as follows.
That is, the laser repair device 103 is disposed on the illumination light source 23, the relay lens 24, and the optical path between the illumination light source 23 and the relay lens 24 in order to project projection light having a predetermined pattern onto the glass substrate 2. The projection pattern grating 25 is further provided. Further, the image processing unit 12 c in the laser repair device 103 also functions as a part of the remaining defect detection unit 22 in the laser repair device 101 in addition to the same function as the image processing unit 12 in the laser repair device 101. Therefore, the imaging unit 11 not only captures an image similar to that in the first embodiment, but also captures an image used by the image processing unit 12c to detect a residual defect. That is, in the third embodiment, the function of the remaining defect detection unit 22 of the first embodiment is realized by the imaging unit 11, the image processing unit 12c, the illumination light source 23, the relay lens 24, and the projection pattern grid 25.

  In the third embodiment, a part having an opening and a light shielding part is called a “projection pattern grid”. In the projection pattern grid 25, a predetermined specific pattern such as a cross pattern is formed by the opening and the light shielding portion. Hereinafter, this specific pattern is referred to as a “projection pattern”.

  The projection pattern grating 25 may be, for example, a transparent material plate partially provided with a light-shielding film, or a light-shielding material plate with holes formed therein, and spatial light using transmissive liquid crystal. It may be a modulator.

  Also, the projection pattern grating 25 can be realized by DMD. In that case, the optical path of the illumination light is different from that in FIG. That is, the illumination light emitted from the illumination light source 23 is reflected on the optical path to the glass substrate 2 through the relay lens 24 when reflected by the micro mirror in the DMD on state, and is reflected by the micro mirror in the off state. And the relay lens 24 are reflected in different directions. Similarly, the projection pattern grating 25 can be realized by a spatial light modulator using a reflective liquid crystal.

Furthermore, the angle phi ₂ the projected pattern to the surface of the glass substrate 2 is _projected, i.e. the angle phi ₂ constituting the optical axis of the relay lens 24 is an xy plane can be determined depending on the embodiment.

  The operation of the laser repair apparatus 103 configured as described above is the same as that of the flowchart of FIG. 2, but the operation of step S106 is more concrete in the third embodiment. Therefore, in the following, details of the operation of the laser repair apparatus 103 in step S106 will be described with reference to FIG.

In step S106, the illumination light source 5 is turned off and the illumination light source 23 is turned on in order to increase the detection accuracy of the remaining defects. The illumination light source 23 emits illumination light from the direction of the angle φ ₂ with respect to the glass substrate 2 toward the center of the visual field of the imaging optical system, that is, toward the position of the first defect extracted as the defect portion G in step S103. Irradiate.

  The cross-sectional shape of the illumination light beam emitted from the illumination light source 23 is formed into a specific shape by the projection pattern grating 25. Hereinafter, the illumination light in which the cross-sectional shape of the beam is formed in a specific shape by the projection pattern grating 25 is referred to as “pattern light”. The pattern light reaches the surface of the glass substrate 2 through the relay lens 24.

  Similarly to the second embodiment, for the sake of simplification of description in the third embodiment, it is assumed that the surface of the glass substrate 2 should be flat if there are no defects or residual defects. However, it is obvious that the third embodiment can be modified by a method similar to the modification of the second embodiment so as to be able to cope with the case where there are irregularities due to a normally formed circuit pattern. is there.

If there is no residual defect and the surface of the glass substrate 2 is flat, the pattern light applied to the glass substrate 2 through the relay lens 24 forms a pattern corresponding to the projection pattern and the angle φ ₂ to form the glass substrate. 2 is projected onto the surface. However, if there is a residual defect higher than the surroundings, the pattern light is projected with the pattern distorted at the boundary between the portion where the residual defect exists and the portion where the residual defect does not exist.

  In other words, the distortion of the projected pattern means that there is a residual defect having a height on the surface of the glass substrate 2 that should be essentially flat. Therefore, the height information in the third embodiment is information indicating that “the projected pattern is distorted, so that there is a residual defect having a height”, or “the pattern is projected without distortion. It contains information indicating that there are no residual defects.

  Therefore, in step S106 of the third embodiment, the imaging unit 11 images the glass substrate 2 in the state where the pattern light is projected on the glass substrate 2, and the image data is captured in the same manner as in step S102. The data is output to the processing unit 12c. The image processing unit 12c determines the presence / absence of a residual defect by determining the presence / absence of pattern distortion based on the received data. An example of residual defect detection by the image processing unit 12c will be described below with reference to FIG.

FIG. 7 is a diagram for explaining the detection of residual defects in the third embodiment. Note that the projection pattern in the example of FIG. 7 is a cross-shaped pattern.
In step S106, the imaging unit 11 images the glass substrate 2 in a situation where the illumination light source 5 is turned on and the illumination light source 23 is turned off, as in step S102 of FIG. Then, a residual defect image (not shown) including the residual defect portion Gb corresponding to the residual defect is obtained.

  Further, the remaining defect image Dh in FIG. 7 is an image obtained by the imaging unit 11 imaging the glass substrate 2 in a state where the illumination light source 5 is turned off and the illumination light source 23 is turned on and the pattern light is projected in step S106. It is. In some cases, the circuit patterns C1 and C2 as shown in the defect image Da of FIG. 3 are shown in the residual defect image (not shown) or the residual defect image Dh. However, for the sake of visibility of the drawing, the remaining defect image Dh in FIG. 7 shows only the remaining defect portion Gb corresponding to the remaining defect and the shape corresponding to the distorted projected pattern Ia.

  In step S106, the image processing unit 12c further generates a difference image (not shown) from the captured remaining defect image (not shown) and the reference image Db shown in FIG. The pattern light shape image Di of FIG. 7 is acquired by generating and binarizing the generated difference image. In the pattern light shape image Di, a shape corresponding to the distorted pattern Ia is extracted.

  The pattern light shape reference image Dj in FIG. 7 is an ideal binarized image that should be obtained as the pattern light shape image Di when there is no remaining defect. The pattern light shape reference image Dj is prepared in advance.

  For example, the stage 1 holds a flat glass substrate on which no circuit pattern has yet been generated, and the illumination light source 23 projects the projection pattern onto the glass substrate via the projection pattern grid 25. Then, when the imaging unit 11 images the glass substrate and the image processing unit 12c binarizes the image captured by the imaging unit 11, a pattern light shape reference image Dj is obtained. In the pattern light shape reference image Dj, an undistorted state pattern Ib is shown.

Alternatively, without performing the actual imaging, the image processing section 12c is, the angle phi ₂ to the projection optical axis of the pattern light makes with the xy plane, based on the shape of the projected pattern to generate a pattern light shape reference image Dj You can also. In any case, the laser repair device 103 acquires the pattern light shape reference image Dj in advance, and stores the data of the pattern light shape reference image Dj in a storage device (not shown).

  In FIG. 7, in both the pattern light shape image Di and the pattern light shape reference image Dj, the background region is expressed in white, the pattern Ia or Ib portion is expressed in black, and white is “0”. Corresponding to the value, black corresponds to a value of “1”.

  In step S106, the image processing unit 12c compares the pattern light shape image Di and the pattern light shape reference image Dj to detect the presence / absence of distortion of the pattern light. For example, the image processing unit 12c generates a difference image between the pattern light shape image Di and the pattern light shape reference image Dj, thereby calculating a size of a different portion in the pattern light shape image Di and the pattern light shape reference image Dj. . If the calculated size is equal to or larger than the threshold value, the image processing unit 12c may determine that the pattern is projected with distortion. In the example of FIG. 7, since the shape of the pattern Ia in the pattern light shape image Di and the shape of the pattern Ib in the pattern light shape reference image Dj are clearly different, the image processing unit 12c detects distortion. That is, the image processing unit 12c detects a remaining defect.

  Then, instead of the remaining defect detection unit 22 in FIG. 1, the image processing unit 12 c performs the determination in step S <b> 107 in the same manner as the remaining defect detection unit 22. The subsequent processing is the same as in FIG. 2 of the first embodiment.

FIG. 8 is a diagram illustrating an example of a projection pattern used in the third embodiment. FIG. 8 is a diagram showing the opening of the projection pattern grid 25 in black and the light shielding part in white.
As shown in FIG. 8, any pattern such as a cross-shaped projection pattern Pa, lattice-like projection patterns Pb and Pd, and concentric projection patterns Pc can be used as the projection pattern. The size of the projection pattern and the interval between the lines are preferably determined as appropriate according to the size of the remaining defect to be detected.

  In the case where there are irregularities due to the circuit pattern normally formed on the glass substrate 2, the glass substrate 2 is easy to detect the distortion caused by the height of the residual defect when the same projection pattern is projected. It may depend on the wiring direction and density of the circuit pattern formed thereon. For example, it is preferable to use an appropriate projection pattern grid 25 according to the design data of the glass substrate 2 or the like.

The third embodiment has been described above. Subsequently, a fourth embodiment will be described.
The fourth embodiment is an embodiment in which the height of a substrate is measured using a confocal unit and a residual defect having a height is detected. Hereinafter, the fourth embodiment will be described with reference to FIGS.

FIG. 9 is a configuration diagram of the laser repair device 104 according to the fourth embodiment. Hereinafter, the configuration of the laser repair device 104 will be described in comparison with FIG.
The laser irradiation optical system in the laser repair device 104 is the same as that shown in FIG.

  The imaging optical system in the laser repair device 104 is partly different from FIG. That is, the beam splitter 34 is arranged between the illumination light source 5 and the relay lens 6, and the illumination light emitted from the illumination light source 5 passes through the beam splitter 34 and then reaches the beam splitter 7 via the relay lens 6. , Reflected by the beam splitter 7, transmitted through the beam splitter 8, and irradiated on the glass substrate 2 through the objective lens 9.

  Reflected light from the glass substrate 2 passes through the beam splitter 8 through the objective lens 9, is reflected by the beam splitter 7, reaches the beam splitter 34 through the relay lens 6, is reflected by the beam splitter 34, and is imaged. Incident on the part 11. The imaging optical system in the laser repair apparatus 104 of FIG. 9 is configured such that the light receiving element of the imaging unit 11 is positioned conjugate with the surface of the glass substrate 2. The imaging unit 11 outputs various captured images to the image processing unit 12d as in the first embodiment.

  Further, the laser repair apparatus 104 in FIG. 9 includes a confocal unit similar to the confocal microscope, instead of the remaining defect detection unit 22 in FIG. The image processing unit 12d of FIG. 9 in the fourth embodiment not only performs the same function as the image processing unit 12 of FIG. 1 in the first embodiment, but also performs data processing output from the confocal unit. Thereby, the height information regarding the height of the glass substrate 2 is acquired. In other words, the image processing unit 12 d also has a function corresponding to a part of the remaining defect detection unit 22.

  The confocal unit in the fourth embodiment includes a laser light source 26, a mirror 27, a beam splitter 28, a two-dimensional scanning mechanism 29, a condensing lens 30, a condensing lens 31, a pinhole plate 32, and a photodetector 33. Further, the confocal unit shares the beam splitter 7, the beam splitter 8, and the objective lens 9 with the imaging optical system. The laser light source 26 is a type of laser light source used for general confocal laser microscope observation. The laser light from the laser light source 26 does not have a physical influence on defects and residual defects.

  9 has a function of moving the relative positions of the objective lens 9 and the glass substrate 2 in the x and y directions as well as the stage 1 of FIG. It also has a function to move. Therefore, the movement / drive control unit 3d in FIG. 9 only controls the relative movement in the x direction and the y direction between the glass substrate 2 and the objective lens 9, similarly to the movement / drive control unit 3 in FIG. Also, the relative movement in the z direction is controlled.

  The relative movement in the z direction between the glass substrate 2 and the objective lens 9 is realized by controlling a motor (not shown) or the like so that a control unit (not shown) moves the optical system of the confocal unit in the z direction. May be.

Acquisition of the height information of the glass substrate 2 by the confocal unit is as follows.
That is, when the laser light source 26 that functions as a point light source emits laser light, the laser light is reflected by the mirror 27, passes through the beam splitter 28, and reaches the two-dimensional scanning mechanism 29. The two-dimensional scanning mechanism 29 is a scanning mechanism using a galvanometer mirror, for example. The two-dimensional scanning mechanism 29 realizes scanning of the glass substrate 2 in the x direction and the y direction with the laser light incident from the beam splitter 28.

  The laser beam reflected by the two-dimensional scanning mechanism 29 reaches the beam splitter 7 through the condenser lens 30, passes through the beam splitters 7 and 8, and is irradiated onto the glass substrate 2 through the objective lens 9. The The laser light reflected from the surface of the glass substrate 2 passes through the beam splitters 8 and 7 through the objective lens 9, then reaches the two-dimensional scanning mechanism 29 through the condenser lens 30, and reaches the two-dimensional scanning mechanism 29. , Reaches the beam splitter 28, is reflected by the beam splitter 28, and reaches the pinhole plate 32 via the condenser lens 31.

  A pinhole 32a is opened in the pinhole plate 32, and the photodetector 33 detects the intensity of the reflected light that has passed through the pinhole 32a. The pinhole plate 32 is arranged so that the pinhole 32a is in a conjugate position with the condensing position of the objective lens 9. Therefore, most of the reflected light from other than the focal point of the objective lens 9 is blocked by the light shielding portion of the pinhole plate 32.

  Therefore, the light detector 33 detects the intensity of the reflected light and the position information in the z direction at that time while the movement / drive control unit 3d performs control to move the stage 1d and the glass substrate 2 relative to each other in the z direction. The height information of the glass substrate 2 is acquired.

For example, the movement and drive control unit 3d is the z-coordinate of the stage 1d, changing the order at a predetermined interval Δz from z = _{z s} to _{z =} z s + NΔz (N is a positive integer). Then, two-dimensional scanning in the x-direction and y-direction is performed on the (N + 1) different z-coordinates by the two-dimensional scanning mechanism 29, and light is transmitted for each point represented by a set of x-coordinate and y-coordinate. The detector 33 detects the intensity of the reflected light and stores it.

  Then, with respect to each point represented by a set of the x coordinate and the y coordinate, data of detection intensity that changes according to the z coordinate is obtained, and the z coordinate at which the detection intensity reaches a peak represents the height of the point. Therefore, the photodetector 33 acquires the height of each point represented by the set of the x coordinate and the y coordinate by performing a process of recognizing the peak of the detected intensity that changes according to the z coordinate. The photodetector 33 outputs the acquired height to the image processing unit 12d in association with a set of x and y coordinates. As described above, the photodetector 33 in the fourth embodiment includes not only the light receiving element but also the storage unit and the processing unit.

  Based on the data received from the photodetector 33, the image processing unit 12d generates binary image data in the same format as the defect shape image Dd in FIG. 3 for the laser shape control unit 19 to control the driver 20. To do. That is, a binary image in which pixels in a range having a height to be regarded as a residual defect are represented by a value “1” and pixels belonging to the other background area are represented by a value “0” is converted into an image processing unit 12d. Is generated and output to the laser shape controller 19.

  Here, for example, a range having a height equal to or higher than a predetermined threshold may be detected by the image processing unit 12d as a remaining defect range. Alternatively, the image processing unit 12d may dynamically determine the reference based on the height distribution in the data output from the photodetector 33, and recognize the remaining defect range based on the determined reference. In any case, the photodetector 33 and the image processing unit 12d measure the height of the glass substrate 2 based on the detection intensity pattern of light that changes according to the z coordinate, and based on the measured height, the glass It functions as a convex portion detecting means for detecting a convex portion having a height on the substrate 2 as a remaining defect.

The range scanned by the two-dimensional scanning mechanism 29 includes at least the first defect range. That is, the range including the defect portion G in the defect shape image Dd in FIG. 3 corresponds to the object to be scanned. Further, with respect to the z direction, the interval Δz and the integer N may be values determined appropriately from previous experiments. Further, the photodetector 33 may perform an appropriate interpolation process for peak recognition. The start coordinate z _s of the relative movement in the z direction will be described later with reference to FIG.

  The height information in the fourth embodiment includes the specific height of each point in the remaining defect range as described above. Therefore, the output level of the laser oscillator 14 may be changed according to the specific height of the remaining defect obtained as the height information. For example, the image processing unit 12d or a control unit (not shown) calculates an average value of the heights in the range of the remaining defects, and the laser oscillator 14 is configured so that the laser light is emitted at a higher output as the average value is larger. The output level may be controlled. Other than the average value, an appropriate representative value can be used.

  When the laser oscillator 14 irradiates the laser beam for correction with the intensity corresponding to the height of the remaining defect, the following effects can be obtained. That is, it is possible to reduce the number of times that the detection of residual defects and laser irradiation are repeated, shorten the correction time, and the laser beam is not irradiated with a higher output than necessary for defects with a low height. Occurrence can be suppressed.

Next, the operation of the laser repair apparatus 104 in the fourth embodiment will be described with reference to the flowchart of FIG.
The difference between the flowchart of FIG. 2 and FIG. 10 in the first embodiment is the following two points. The first point is that step S201 is executed immediately after the start of the process of FIG. The second point is that step S106 in FIG. 2 is replaced with step S207 in FIG.

  Except for these two points, the processing of FIG. 10 is the same as that of FIG. That is, Steps S101 to S105 in FIG. 2 correspond to Steps S202 to S206 in FIG. 10, and Steps S107 to S108 in FIG. 2 correspond to Steps S208 to S209 in FIG. Further, the determination in step S107 is performed by the residual defect detection unit 22 in FIG. 1, and the determination in step S208 is performed by the image processing unit 12d in FIG. It is the same.

Therefore, only step S201 and step S207 will be described below.
In step S201, the confocal unit measures the standard height of the glass substrate 2.

  For example, as in the second embodiment, the precondition that the surface of the glass substrate 2 should be flat if there are no defects or residual defects in the current process, which is a target for detecting and correcting defects, is established. In this case, the confocal unit may operate as follows.

  That is, the confocal unit measures the height of the glass substrate 2 by the method described with reference to FIG. The range of scanning in the x direction and y direction by the two-dimensional scanning mechanism 29 is, for example, the field of view of the imaging unit 11. Further, the range in which the relative movement in the z direction is performed may be determined according to the specifications of the glass substrate 2 and the like.

  As a result of the measurement, the photodetector 33 recognizes the height of each point within the measurement range. Therefore, the photodetector 33 is based on the precondition that the surface of the glass substrate 2 should be flat if there is no residual defect, and based on the recognized height distribution, the glass substrate 2 in the field of view of the imaging unit 11. Get the standard height of.

For example, since the range of the remaining defects is not wider than the range of the first defect, the photodetector 33 may calculate the average height outside the range of the first defect as the standard height.
FIG. 10 is a flowchart showing an operation related to one glass substrate 2, but step S201 may be executed only once in advance for a specific process of a specific model, that is, not executed for each glass substrate 2. Also good. In other words, if the confocal unit performs the height measurement using the unit pattern portion previously known to be free of defects used for capturing the reference image Db of FIG. 3 in step S201. Step S201 may not be repeated for each glass substrate 2.

  In this case, the height of each point in the measurement range recognized as a result of measurement by the photodetector 33 is the standard height of each point. Therefore, even when unevenness due to a normally formed circuit pattern exists on the glass substrate 2, the presence or absence of residual defects is detected from the difference between the standard height and the actual height of the glass substrate 2 to be corrected at each point. Is possible.

  In any case, in step S201, a standard height for determining the presence or absence of a remaining defect is measured based on the height information. Further, the photodetector 33 stores the measured standard height in a storage device (not shown) provided in the laser repair device 104.

In step S207, the confocal unit measures the height of the glass substrate 2 by the method described with reference to FIG. The range for measuring the height may be, for example, the range of the visual field of the imaging unit 11, the range corresponding to the first defect detected in step S204, or the minimum rectangular range including the first defect. Also, start coordinate z _s of the relative movement in the z direction as described with respect to FIG. 9, for example, it may be a standard height measured at step S201, may be correspondingly lower by the height of the predetermined margin than the standard height.

  In step S207, the photodetector 33 outputs the height of each point in the measurement range measured by the confocal unit to the image processing unit 12d in association with the x coordinate and y coordinate of each point. For each point in the measurement range, the image processing unit 12d calculates a difference by subtracting the standard height from the height output from the photodetector 33, and detects a residual defect based on the calculated difference. For example, the image processing unit 12d recognizes a range including the calculated difference as a residual defect range as a residual defect range, generates a binary image indicating the position and range of the residual defect, and performs laser shape control. To the unit 19.

  FIG. 11 is a diagram for explaining detection of residual defects in the fourth embodiment. FIG. 11 includes a cross-sectional view Q of a residual defect by a certain cross section L perpendicular to the xy plane, and a plan view showing the residual defect by contour lines.

In FIG. 11, the standard height measured in step S201 is represented as “z ₀ ”. Further, in the plan view, the height z ₁ or more ranges R1, and height z ₂ or more ranges R2, height is z ₃ above range R3, are shown with a straight line showing a cross section L .

For example, when z ₁ = z ₀ + ε, where ε is a predetermined allowable error, the image processing unit 12d determines that each point in the range R1 has a measured height and a standard height z _{0 in} step S207. Is the range of the remaining defects because the difference between the two is the allowable error ε or more ”. When the residual defect range R1 is detected in this way, the image processing unit 12d sets a binary image in which a value “1” is set for the pixels inside the range R1 and a value “0” is set for the pixels outside the range R1. It is generated and output to the laser shape controller 19. Then, when the process proceeds from step S208 to step S205 and step S206, laser irradiation is performed on the region R1.

Alternatively, if z ₂ = z ₀ + ε, the image processing unit 12d will detect as the range of the range R2 residual defect.
Although the fourth embodiment has been described above, the configuration of the confocal unit is not limited to that shown in FIG. 9, and the pinhole plate 32 can be replaced with another component depending on the configuration of the confocal unit. is there.

  In FIG. 9 of the fourth embodiment, a pinhole plate 32 in which a pinhole 32a is opened is used, and the pinhole 32a is an aperture for blocking reflected light from a position other than the in-focus position of the objective lens 9. Is functioning as However, in the height measurement by the confocal unit, it is possible to use various confocal stop portions having a stop arranged at a position conjugate with the in-focus position of the objective lens 9 instead of the pinhole plate 32. It is. For example, a Nipkow disk in which a large number of pinholes are spirally opened can be used as a confocal stop.

Hereinafter, a modified example in which the pinhole plate 32 of FIG. 9 is replaced will be described with reference to FIGS. 12 and 13.
FIG. 12 is a diagram illustrating an example of a confocal stop unit used in a modification of the fourth embodiment. Each of the four types of disks illustrated in FIG. 12 is a rotary disk that is rotated at a constant speed by a motor (not shown).

  The slit disk 51 has a large number of slits formed over the entire surface. As illustrated, the shape of each slit is a line. Instead of slits, it is also possible to use a disk with pinholes randomly opened on the entire surface.

The slit disk 52 is a part of the slit disk 51 provided with an opening 53 that transmits light. The reason why the opening 53 is provided is as follows.
Depending on the configuration of the laser repair device, there may be a configuration in which the slit disk 51 of the confocal unit is disposed on the optical path of the laser light emitted from the laser oscillator 14. In that case, it is necessary to prevent the laser beam irradiated for correcting the defect or the remaining defect from being blocked by the slit disk 51. Therefore, for example, the laser repair device is configured so that the rotation axis of the slit disk 51 is supported so as to be able to advance and retract, and the slit disk 51 is retracted to a position that does not block the optical path of the laser light when the laser oscillator 14 emits the laser light. It is also necessary.

  However, if the slit disk 52 having the opening 53 is used instead of the slit disk 51, a mechanical part for retracting the slit disk 51 becomes unnecessary. This is because when the laser oscillator 14 irradiates laser light, it is only necessary to control the rotation angle of the slit disk 52 so that the optical path of the laser light passes through the opening 53.

  Further, a slit disk 59 in which the opening 60, the light shielding part 61, the slit part 62, and the light shielding part 63 are sequentially formed in the circumferential direction can also be used. A plurality of line-like slits similar to the slit disks 51 and 52 are formed in the slit portion 62.

  Similarly, in the pinhole disk 64, an opening 65, a light shielding portion 66, a random pinhole pattern portion 67, and a light shielding portion 68 are sequentially formed in the circumferential direction. The pinhole disc 64 is obtained by replacing the slit portion 62 of the slit disc 59 with a random pinhole pattern portion 67 in which a large number of pinholes are randomly opened. The slit disk 59 and the pinhole disk 64 may have, for example, the characteristics disclosed in Patent Document 3 above.

As described above, the various rotary disks illustrated in FIG. 12 can be used in, for example, a laser repair apparatus configured as shown in FIG.
FIG. 13 is a configuration diagram of a laser repair device 105 according to a modification of the fourth embodiment. The configuration of the laser repair device 105 is simpler than that of the laser repair device 104 in FIG. 9, and is close to the configuration of the laser repair device 101 in FIG.

  Since the laser repair apparatus 105 in FIG. 13 does not require scanning in the x direction and the y direction, the difference from the laser repair apparatus 104 in FIG. 9 is that a component such as the two-dimensional scanning mechanism 29 is unnecessary. Since the scanning is unnecessary, the structure of the laser repair device 105 is simplified, and the time required for detecting the remaining defects is shortened.

Moreover, the difference between the laser repair apparatus 101 of FIG. 1 and the laser repair apparatus 105 of FIG. 13 is as follows.
The stage 1d and the movement / drive control unit 3d in FIG. 13 are the same as those in FIG. 9, and realize relative movement of the glass substrate 2 and the objective lens 9 in the z direction.

  Instead of the remaining defect detector 22 shown in FIG. 1, the laser repair device 105 is provided with a rotary disk 35 between the beam splitter 8 and the objective lens 9. The rotary disk 35 is, for example, a disk having a large number of slits or a large number of pinholes as shown in FIG. If there is a slit, pinhole, or opening of the rotary disk 35 on the optical axis of the objective lens 9, the light can pass through the rotary disk 35. The position of the rotary disk 35 is determined in the z direction so that the position of the slit or pinhole located on the optical axis of the objective lens 9 is conjugate with the focusing position of the objective lens 9 on the glass substrate 2 side. Is placed.

  In addition to the same function as the image processing unit 12 in the laser repair device 101, the image processing unit 12e also functions as a part of the remaining defect detection unit 22 in the laser repair device 101. Therefore, the imaging unit 11 not only captures an image similar to that in the first embodiment, but also captures an image used by the image processing unit 12e to detect a residual defect.

  That is, the imaging unit 11 captures the glass substrate 2 a plurality of times while the rotary disk 35 is rotating, and the image processing unit 12e acquires the height information of the glass substrate 2 based on the plurality of images. Then, the image processing unit 12e detects the presence or absence of a remaining defect based on the height information, and further recognizes the position and range of the remaining defect.

  That is, in FIG. 13, the stage 1d, the movement / drive control unit 3d, the rotary disk 35, the imaging unit 11, and the image processing unit 12e function as a confocal unit, in other words, the remaining defect detection unit of FIG. Performs the same function as 22. The imaging unit 11 and the image processing unit 12e function as a light detection unit that detects the intensity of light that has passed through the aperture at a position conjugate with the in-focus position of the objective lens 9.

  For example, when the rotary disk 35 is a disk having a large number of pinholes randomly formed on the entire surface or the slit disk 52 of FIG. 12, the height information is acquired in the laser repair device 105 of FIG. 13 as follows. .

  Under the control of the movement / drive control unit 3d, the imaging unit 11 is attached to the glass substrate 2 while the illumination light source 5 is irradiating illumination light while performing relative movement in the z direction as in the fourth embodiment. Repeat imaging. For example, it is assumed that imaging is performed for (N + 1) different z coordinates as in the fourth embodiment.

  In this case, the image processing unit 12e examines which of the (N + 1) images has the highest luminance for each point represented by a set of x and y coordinates. Then, the image processing unit 12e acquires, for each point, the z coordinate when the image having the highest luminance is captured as the height of the point. Alternatively, the image processing unit 12e performs appropriate interpolation based on the curve of the luminance change according to the z coordinate, calculates the z coordinate that should have the highest luminance, and uses the calculated z coordinate as the height of each point. You may get as

  Further, when the rotary disk 35 is the slit disk 59 of FIG. 12, imaging through the opening 60 and imaging through the slit 62 are respectively performed for (N + 1) different z coordinates. 11 does. The imaging timing of the imaging unit 11 and the rotation angle of the slit disk 59 are synchronized by a timing control unit (not shown).

  The image captured through the opening 60 is a non-confocal image, and the image captured through the slit 62 is an image obtained by combining the confocal image and the non-confocal image. Therefore, the image processing unit 12e calculates the difference for each point by subtracting the product of the luminance in the image captured through the opening 60 and the predetermined coefficient from the luminance in the image captured through the slit unit 62. . The predetermined coefficient is a constant determined by the characteristics of the slit disk 59, and the calculated difference is the luminance corresponding to the confocal image.

  In this way, the image processing unit 12e calculates the luminance corresponding to the confocal image for each of (N + 1) different z coordinates. Then, the image processing unit 12e acquires the z coordinate at which the luminance corresponding to the confocal image is maximized at each point as the height of the point. Alternatively, the image processing unit 12e may perform appropriate interpolation as described above.

The same applies when a pinhole disk 64 is used instead of the slit disk 59.
As described above, according to the modification of the fourth embodiment, the height information of the glass substrate 2 can be acquired by the easily configured confocal unit without performing scanning in the x direction and the y direction. .

The fourth embodiment and its modifications have been described above. Subsequently, a fifth embodiment obtained by modifying the fourth embodiment will be described.
In the fifth embodiment, not only residual defects but also defects are detected using a confocal unit. That is, in the fifth embodiment, the imaging optical system of the laser repair device 104 in FIG. 9 is only used to acquire an image to be displayed on the monitor 13 for confirmation by an inspector. Therefore, if confirmation by an inspector is unnecessary, the imaging optical system can be omitted.

  In step S203 and step S204 in FIG. 10, in the fifth embodiment, the height measurement by the confocal unit similar to step S207 and the defect extraction by the image processing unit 12d based on the measured height are performed. Replaced. Further, as described below with reference to FIG. 14, the fifth embodiment can be further modified so that the height is measured only once per defect.

FIG. 14 is a diagram illustrating a modification of the fifth embodiment.
When the defect image Dk in FIG. 14 is assumed to be imaged in step S203 for confirmation by the inspector after the relative movement to the defect position in step S202 in FIG. Is an example of an image acquired by imaging the glass substrate 2. As described above, it is not always necessary to capture the defect image Dk, but the defect image Dk is shown in FIG. 14 for convenience of explanation.

  In the defect image Dk, normally formed circuit patterns C3 to C6 are shown. Further, the defect image Dk includes a defect portion G2 corresponding to a defect generated over the circuit patterns C4 and C5.

In the modification of the fifth embodiment, height measurement by a confocal unit is performed instead of step S204 in FIG. As a result, the image processing unit 12d in FIG. 9 recognizes a range R4 that is equal to or higher than _a certain height z _a based on the output from the photodetector 33. Further, the image processing unit 12d recognizes a range R5 having _a height z _b (= z _a + Δz) or more using an appropriate interval Δz, and ranges R6 and R7 having a height z _c (= z _b + Δz) or more. Recognize In this example, there is no range higher than the height z _d (= z _c + Δz).

A contour diagram Dl in FIG. 14 is a diagram expressing these ranges R4 to R7 with contour lines together with the circuit patterns C3 to C6 for convenience of explanation.
The image processing unit 12d recognizes the range R4 as the first defect range, generates a binary image indicating the range R4 as a correction target, and outputs the binarized image to the laser shape control unit 19. In step S205 and step S206, a laser beam is irradiated onto a range on the glass substrate 2 corresponding to the range R4.

  In the modified example of the fifth embodiment, thereafter, the measurement by the confocal unit for detecting the remaining defect is not performed again. That is, step S207 is deleted in the modification of the fifth embodiment.

Further, determination in step S208 is whether the height z Delta] z is higher by the height z _b more range than _a prescribed range R4 of the current correction target is present, is replaced by a determination that. In the example of FIG. 14, the height z _b more ranges R5 are present, the residual defects after the modification to the range R4 present image processing unit 12d determines.

  The reason for making such a determination is that the thicker the defect or the remaining defect, the more the defect or the remaining defect cannot be removed unless more laser light is irradiated. Therefore, by setting the output level of the laser oscillator 14 to an appropriate value according to the interval Δz, it is expected that the following two points are approximately established after the laser irradiation with respect to the range R4.

A portion included in the range R4 but not included in the range R5 has a thickness of defects so that it was removed by one laser irradiation.
The portion included in the range R5 has a certain degree of defect thickness, so that it was removed by the thickness Δz by one laser irradiation and the height was lowered, but it still remains as a residual defect.

  Therefore, the image processing unit 12d recognizes the recognized range R5 as a residual defect range, generates a binary image indicating the range R5 as a correction target, and outputs the binarized image to the laser shape control unit 19. In step S205 and step S206, a laser beam is irradiated onto a range on the glass substrate 2 corresponding to the range R5.

Subsequently, instead of the determination in step S208, the image processing unit 12d determines whether or not there is a range equal to or higher than the height z _c (= z _b + Δz), as described above. Since the ranges R6 and R7 exist, the image processing unit 12d recognizes the ranges R6 and R7 as remaining defect ranges, generates a binary image indicating the ranges R6 and R7 as correction targets, and generates a laser shape control unit. 19 output. In step S205 and step S206, a laser beam is irradiated onto a range on the glass substrate 2 corresponding to the ranges R6 and R7.

Subsequently, instead of the determination in step S208, the image processing unit 12d determines whether or not there is a range equal to or higher than the height z _d (= z _c + Δz) as described above. Since such a range does not exist, the image processing unit 12d determines that no remaining defect remains, and the process proceeds to step S209.

  As described above, in the modification of the fifth embodiment, the height measurement by the confocal unit is performed only once for each initial defect. In other words, the determination of whether there is a remaining defect to be further corrected after the defect correction is based solely on height information obtained from measurements made prior to laser irradiation of the defect, Measurement for acquiring new height information is not performed every time laser irradiation is performed.

  However, as described above, since the presence or absence of the remaining defects is determined based on the approximate prediction, the range of the remaining defects may not actually be as predicted. For example, in the above example, if the imaging unit 11 images the glass substrate 2 after laser irradiation with respect to the range R5, an image such as the residual defect image Dm or Dn in FIG. 14 may be obtained. In the remaining defect images Dm and Dn, the range R4 is represented by a dotted line to help understanding.

  The remaining defect image Dm includes a remaining defect portion G3 corresponding to an actual remaining defect extending over the circuit patterns C4 and C5. According to the above approximate prediction, since there should be residual defects in the ranges R6 and R7 at this stage, the prediction is off.

  The residual defect image Dn is similar to the above approximate prediction in that it includes a residual defect part G4 partially overlapping with the circuit pattern C4 and a residual defect part G5 partially overlapping with the circuit pattern C5. is there. However, in a detailed shape, the range R6 and the remaining defect portion G4 are different, and the range R7 and the remaining defect portion G5 are different. Therefore, in this case as well, the prediction is not accurate.

  Therefore, in this modification of the fifth embodiment, for example, when the image processing unit 12d determines that there is no remaining defect, the imaging unit 11 images the glass substrate 2 and monitors it via the image processing unit 12d. You may display the image by which 13 was imaged. Then, the inspector may look at the monitor 13 to confirm the actual presence / absence of the remaining defect to be corrected, and instruct the laser repair device 104 whether re-correction is necessary.

Further, for simplification of description, it is assumed in the above that the intervals of the heights z _a , z _b , and z _c are equal intervals Δz, but the intervals may be different. For example, in the example of FIG. 14, the image processing unit 12 d recognizes a range of height z _a or higher as the first defect, recognizes a range of height z _b or higher as the first remaining defect, and has a height z _c or higher. Is recognized as the second remaining defect, but the intervals of the heights z _a , z _b , and z _c may be unequal intervals. The image processing unit 12d may dynamically determine the heights z _b and z _c according to the height gradient within the range of the first defect, and as _a result, the heights z _a , z _b , z The intervals of _c may be unequal intervals. In that case, it is preferable that the image processing unit 12d or a control unit (not shown) controls the output level of the laser oscillator 14 in accordance with the intervals of the heights z _a , z _b , and z _c .

  The fifth embodiment and the modifications thereof have been described above. Subsequently, a sixth embodiment will be described. The sixth embodiment is an embodiment in which a remaining defect is detected using a non-contact type height measurement sensor.

That is, in the sixth embodiment, a non-contact type height measurement sensor such as a laser length measuring device is used as the remaining defect detection unit 22 in FIG. 1 in order to measure the height of the glass substrate 2.
For example, in step S <b> 106 of FIG. 2, the laser length measuring device measures the height of the range in the imaging field of view of the surface of the glass substrate 2. Note that the laser length measuring device measures the height of a plurality of points sampled within the measurement range at appropriate intervals. The measurement result is height information in the sixth embodiment. Then, the laser length measuring device detects a portion higher than the standard height on the surface of the glass substrate 2 by a predetermined threshold or more as a residual defect having a height, and detects the position and range of the detected residual defect in the image of FIG. Notify the processing unit 12.

  The standard height may be a value obtained by the laser length measuring device measuring in advance as in step S201 in FIG. Alternatively, in step S106, the laser length measuring device may dynamically determine the standard height from the distribution of the height within the target range in which the height is measured. Also in the measurement of the standard height, the laser length measuring device measures the height of a plurality of points sampled at appropriate intervals within the measurement range.

  The sixth embodiment has been described above. Subsequently, a seventh embodiment obtained by modifying the sixth embodiment will be described. The seventh embodiment is an embodiment in which not only residual defects but also defects are detected using a non-contact type height measurement sensor.

  That is, in the seventh embodiment, the imaging optical system of the laser repair apparatus 101 in FIG. 1 is only used to acquire an image to be displayed on the monitor 13 for confirmation by an inspector. Then, in the seventh embodiment, step S102 and step S103 in FIG. 2 are replaced with defect extraction processing by a height measuring sensor such as a laser length measuring device. The defect extraction by the height measurement sensor is the same as the method of extracting the remaining defect in the sixth embodiment, and thus the description thereof is omitted.

Although the first to seventh embodiments have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.
For example, the arrangement of optical elements such as a beam splitter and a lens in the laser repair device is not limited to that illustrated in the drawing. Moreover, the combination of the method of detecting a defect and the method of detecting a residual defect is arbitrary, and is not limited to the combinations exemplified in the first to seventh embodiments. Moreover, as long as no contradiction arises, it is also possible to apply the modification similar to the modification illustrated about a certain embodiment to other embodiment.

It is a block diagram of the laser repair apparatus 101 by 1st Embodiment. It is a flowchart which shows operation | movement of the laser repair apparatus 101 in 1st Embodiment. It is a figure which shows the example of the image utilized for the detection of the defect in 1st Embodiment. It is a block diagram of the laser repair apparatus 102 by 2nd Embodiment. It is a figure which shows the example of the image utilized for detection of a residual defect in 2nd Embodiment. It is a block diagram of the laser repair apparatus 103 by 3rd Embodiment. It is a figure explaining the detection of the residual defect in 3rd Embodiment. It is a figure which shows the example of the projection pattern utilized in 3rd Embodiment. It is a block diagram of the laser repair apparatus 104 by 4th Embodiment. It is a flowchart which shows operation | movement of the laser repair apparatus 104 in 4th Embodiment. It is a figure explaining the detection of the residual defect in 4th Embodiment. It is a figure which shows the example of the confocal stop part utilized in the modification of 4th Embodiment. It is a block diagram of the laser repair apparatus 105 in the modification of 4th Embodiment. It is a figure explaining the modification of 5th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1d stage 2 Glass substrate 3, 3d Movement / drive control part 4 Board | substrate inspection apparatus 5 Illumination light source 6, 18, 24 Relay lens 7, 8, 15, 28, 34 Beam splitter 9 Objective lens 10 Imaging lens 11 Imaging part DESCRIPTION OF SYMBOLS 12, 12b-12e Image processing part 13 Monitor 14 Laser oscillator 16, 27 Mirror 17 DMD unit 19 Laser shape control part 20 Driver 21 Light source for repair position confirmation 22 Residual defect detection part 23 Illumination light source 25 Projection pattern grating | lattice 26 Laser light source 29 2 Dimensional scanning mechanism 30, 31 Condensing lens 32 Pinhole plate 32a Pinhole 33 Photo detector 35 Rotary disk 51, 52, 59 Slit disk 53, 60, 65 Opening 61, 63, 66, 68 Light shielding part 62 Slit part 64 pinhole disc 67 random pin Hole pattern portion 101 to 105 Laser repair device C1 to C6 Circuit pattern Da, Dk Defect image Db Reference image Dc, Df Difference image Dd Defect shape image De, Dh, Dm, Dn Remaining defect image Dg Shadow shape image Di pattern light shape image Dj pattern light shape reference image Dl contour map G, G2 defect part Gb, G3 to G5 residual defect part H shadow part Ia, Ib pattern L cross section Pa to Pd projection pattern Q cross section R1 to R7 region

Claims (17)

A defect detection means for detecting a defect to be corrected in a substrate to be inspected and recognizing the position and range of the defect;
The height information related to the height of the substrate in the range of the defect is acquired, and after the correction for the defect detected by the defect detection means, a residual defect to be further corrected is in a part or all of the range of the defect Residual defect detection means for determining whether or not it exists based on the height information;
A laser oscillator that corrects the defect when the defect detection means detects the defect and outputs a laser beam for correcting the remaining defect when the residual defect detection means determines that the residual defect exists; ,
The laser oscillator spatially modulates the laser light according to the position and the range of the defect so that the laser light output from the laser oscillator is irradiated onto the defect detected by the defect detection means, and the laser oscillator Two-dimensional spatial light modulation means for spatially modulating the laser light so that the output laser light is irradiated to the remaining defects on the substrate;
A correction apparatus comprising: The defect detection means includes
Imaging means for imaging the substrate;
An image processing means for detecting the defect and recognizing the position and the range of the defect based on an image obtained by imaging the substrate by the imaging means;
The correction apparatus according to claim 1, further comprising: The defect detection means includes
An objective lens having an optical axis parallel to the height direction of the substrate and irradiating light emitted from a light source onto the substrate;
A relative movement means for moving a relative position between the focusing position of the objective lens and the substrate in the optical axis direction of the objective lens;
Confocal stop means having a stop disposed at a position conjugate with the in-focus position;
Light detection means for detecting the intensity of light that is irradiated onto the substrate through the objective lens, reflected by the substrate, and passed through the diaphragm of the confocal diaphragm means;
The height of the substrate is measured based on a pattern in which the intensity of the light detected by the light detection unit changes according to movement by the relative movement unit, and the height on the substrate is measured based on the measured height. A convex portion detecting means for detecting a convex portion having a height as the defect,
The correction apparatus according to claim 1, further comprising: The convexity detection means included in the defect detection means detects a part having a height equal to or higher than a first height as the defect based on the measured height and is higher than the first height. It also functions as the residual defect detecting means by detecting a portion having a height equal to or higher than a second height as the residual defect.
The correction device according to claim 3. The confocal stop means is a nipou disk having a plurality of pinholes for allowing light to pass through, or a slit disk having a plurality of slits for allowing light to pass through.
The correction device according to claim 3. The defect detection means includes
Non-contact type height measuring means for measuring the height of the substrate without contacting the substrate and detecting a convex portion having a height on the substrate as the defect,
The correction device according to claim 1. The residual defect detection means includes
An objective lens having an optical axis parallel to the height direction of the substrate and irradiating light emitted from a light source onto the substrate;
A relative movement means for moving a relative position between the focusing position of the objective lens and the substrate in the optical axis direction of the objective lens;
Confocal stop means having a stop disposed at a position conjugate with the in-focus position;
Light detection means for detecting the intensity of light that is irradiated onto the substrate through the objective lens, reflected by the substrate, and passed through the diaphragm of the confocal diaphragm means;
The height of the substrate is measured based on a pattern in which the intensity of the light detected by the light detection unit changes according to movement by the relative movement unit, and the height on the substrate is measured based on the measured height. Convex portion detecting means for detecting a convex portion having a height as the remaining defect,
The correction apparatus according to claim 1, further comprising: The residual defect detection means limits a range for measuring the height for detecting the residual defect based on the range of the defect detected by the defect detection means.
The correction device according to claim 7. The confocal stop means is a nipou disk having a plurality of pinholes for allowing light to pass through, or a slit disk having a plurality of slits for allowing light to pass through.
The correction device according to claim 7. In accordance with the height measured by the convex detection means, the laser oscillator changes the output intensity of the laser light applied to the remaining defects on the substrate.
The correction device according to claim 7. The residual defect detection means includes
Non-contact type height measuring means for measuring the height of the substrate in the range of the defect without contacting the substrate and detecting a convex portion having a height on the substrate as the remaining defect,
The correction device according to claim 1. The residual defect detection means further detects the position and range of the residual defect;
The two-dimensional spatial light modulation means spatially modulates the laser light so that the laser light is irradiated to the range of the residual defects detected by the residual defect detection means;
The correction apparatus according to claim 7 or 11, characterized in that The residual defect detection means includes
Illumination means for irradiating illumination light obliquely to the surface of the substrate;
Imaging means for imaging the substrate irradiated with the illumination light by the illumination means;
Based on an image obtained by imaging the substrate by the imaging unit, it is determined whether or not a shadow is generated on the substrate by the illumination light, so that the remaining convex portion having a height on the substrate is obtained. Image processing means for determining whether a defect exists;
The correction apparatus according to claim 1, further comprising: The residual defect detection means includes
Projection means for projecting projection light having a predetermined pattern onto a range on the substrate including the range of the defect;
Imaging means for imaging the substrate on which the projection light is projected by the projection means;
Based on the pattern of the projection light reflected in the image obtained by imaging the substrate by the imaging means and the predetermined pattern, the residual defect that is a convex portion having a height on the substrate is the defect. Image processing means for determining whether or not it exists within the range of
The correction apparatus according to claim 1, further comprising: A correction apparatus having a laser oscillator that outputs a laser beam for correcting a defect on a substrate to be inspected and having a function of irradiating an arbitrary range on the substrate with the laser beam,
Detect defects to be fixed,
Recognizing the position and extent of the defect,
Irradiating the laser beam to the defect according to the position and the range of the recognized defect,
Obtaining height information regarding the height of the substrate in the range of the defects before or after the irradiation of the laser beam;
Based on the acquired height information, it is determined whether or not there are residual defects to be further corrected after irradiation of the laser beam to the defects in a part or all of the range of the defects;
When it is determined that the residual defect exists, the laser beam is irradiated to the residual defect on the substrate.
The correction method characterized by this. A control device that controls a correction device including a laser oscillator that outputs a laser beam for correcting a defect on a substrate to be inspected, and a two-dimensional spatial light modulation unit that spatially modulates the output laser light. And
A defect detection means for detecting a defect to be corrected in the substrate and recognizing a position and a range of the defect;
The height information related to the height of the substrate in the range of the defect is acquired, and after the correction for the defect detected by the defect detection means, a residual defect to be further corrected is in a part or all of the range of the defect Residual defect detection means for determining whether or not it exists based on the height information;
When the defect detection means detects the defect, the laser oscillator is controlled to output a laser beam for correcting the defect, and when the remaining defect detection means determines that the remaining defect exists, Laser control means for controlling the laser oscillator to output a laser beam for correcting a residual defect;
While controlling the two-dimensional spatial light modulation means according to the position and the range of the defect so that the laser light output from the laser oscillator is irradiated to the defect detected by the defect detection means, Modulation control means for controlling the two-dimensional spatial light modulation means so that the laser beam output from the laser oscillator is irradiated onto the remaining defects on the substrate;
A control device comprising: In order to control a correction apparatus comprising: a laser oscillator that outputs a laser beam for correcting a defect on a substrate to be inspected; and a two-dimensional spatial light modulation unit that spatially modulates the output laser light, To the computer connected to the correction device,
Detecting a defect to be corrected in the substrate and recognizing a position and range of the defect;
Controlling the laser oscillator to output a laser beam for correcting the defect when the defect is detected;
Controlling the two-dimensional spatial light modulation means in accordance with the position and the range of the defect so that the detected laser beam is emitted to the detected defect when the defect is detected. When,
Obtaining height information relating to the height of the substrate in the range of the defects before or after irradiation with the laser beam;
Determining, based on the acquired height information, whether or not there are residual defects to be further corrected after correction of the detected defects, in part or all of the range of the defects;
Controlling the laser oscillator to output a laser beam for correcting the remaining defect when it is determined that the remaining defect exists; and
Controlling the two-dimensional spatial light modulation means so that the laser beam output from the laser oscillator is irradiated onto the residual defect on the substrate when it is determined that the residual defect exists;
A program characterized by having executed.