JP5234399B2 - Dicing method - Google Patents

Description

  The present invention relates to a dicing apparatus and a dicing method for dividing a workpiece such as a wafer on which a semiconductor device or an electronic component is formed into individual chips.

  A dicing machine that performs cutting and grooving on workpieces such as wafers on which semiconductor devices and electronic components are formed is a blade that is rotated at high speed by a spindle, a work table that holds the work, and a work after dicing is cleaned. Various moving axes for changing the relative positions of the cleaning means and the blade and the workpiece are provided.

  FIG. 1 shows an example of a dicing apparatus. The dicing apparatus 10 includes a high-frequency motor built-in type spindles 22 and 22 that are arranged to face each other and have a blade 21 and a wheel cover (not shown) attached to the tip, an imaging unit 23 that images the surface of the workpiece W, and a workpiece W. A processing unit 20 having a work table 31 for sucking and holding is provided.

  In addition to the processing unit, the dicing apparatus 10 includes a cleaning unit 52 that spin-cleans the processed workpiece W, a load port 51 that mounts a cassette that stores a large number of workpieces W mounted on the frame F, and a workpiece W. Conveying means 53 for conveying, display means 24 for displaying an image picked up by the image pickup means 23 and inputting an operation to each part, a controller (not shown) for controlling the operation of each part, and the like.

  As shown in FIG. 2, the structure of the processing unit 20 is guided by X guides 34, 34 provided on the X base 36, and is driven by the linear motor 35 in the X direction indicated by XX in the drawing. The X table 33 is provided with a work table 31 via a rotary table 32 that rotates in the θ direction.

  On the other hand, Y tables 41 and 41 guided by Y guides 42 and 42 and driven in the Y direction indicated by YY in the figure by a stepping motor and a ball screw (not shown) are provided on the side surface of the Y base 44. . Each Y table 41 is provided with a Z table 43 that is driven in the Z direction indicated by ZZ in the drawing by driving means (not shown), and the Z table 43 is a built-in high-frequency motor with a blade 21 attached to the tip. The spindle 22 and the imaging means 23 (not shown in FIG. XX2) are fixed. Since the structure of the processing unit 20 is as described above, the blade 21 is index-fed in the Y direction and cut and fed in the Z direction, and the work table 31 is cut and fed in the X direction.

  Both spindles 22 are rotated at a high speed of 1,000 rpm to 80,000 rpm, and a supply nozzle (not shown) for supplying a cutting fluid for immersing the workpiece W in the cutting fluid is provided in the vicinity (for example, (See Patent Document 1).

  Further, in recent years, instead of using such a blade 21, a laser beam having a focused point inside the work W is incident on the work W, and a plurality of modified regions by multiphoton absorption are formed inside the work W. A laser dicing apparatus that expands the work W and divides the work W into individual chips T is also used for processing the work W.

  The laser dicing apparatus is provided with a load port, a conveying means, a work table and the like, similar to the dicing apparatus 10, and a laser head 61 is provided in the processing unit 20 so as to face the spindle 22 as shown in FIG. ing.

  The laser head 61 includes a laser oscillator 61A, a collimator lens 61B, a mirror 61C, a condensation lens 61D, and the like. The laser light L oscillated from the laser oscillator 61A is collimated in the horizontal direction by the collimator lens 61B, The light is reflected in the vertical direction and collected by the condensation lens 61D (see, for example, Patent Document 2).

  When the condensing point of the laser beam L is set inside the thickness direction of the workpiece W placed on the chuck table 31, the laser beam L transmitted through the surface of the workpiece W is collected as shown in FIG. Energy is concentrated at the light spot, and a modified region P such as a crack region, a melted region, a refractive index changing region or the like due to multiphoton absorption is formed in the vicinity of the condensing point inside the workpiece.

  As shown in FIG. 4B, a plurality of reformed regions P are formed side by side inside the workpiece W when the workpiece W is moved in the horizontal direction. In this state, the workpiece W is naturally cleaved starting from the reforming region P, or is cleaved starting from the reforming region P by applying a slight external force. In this case, the workpiece W is easily divided into chips without causing chipping on the front and back surfaces.

In such a dicing apparatus 10 or a laser dicing apparatus, alignment that specifies a cutting position for cutting the work W is performed as a stage before the work W is placed on the chuck table 31 and dicing is started. In the alignment, the image pickup means 23 and the chuck table 31 on which the work W is placed are relatively moved in the XYZθ directions, and alignment standards such as streets and fiducial marks formed on the work W by the image pickup means 23 are set. This is performed by capturing an image and recognizing the shape by a known image processing method.
JP 2002-280328 A JP 2002-192367 A

  However, in such an alignment in which an image picked up by the image pickup means is recognized by the image processing technique, the workpiece W actually picked up by the image pickup means is displayed as the image displayed on the display means 24 shown in FIG. Since the upper alignment reference A is not accurately formed in the same shape as the reference shape B registered in advance in the dicing apparatus, the alignment reference shape cannot be recognized and an error may occur.

  In such a case, conventionally, an operator directly inputs a position on the workpiece on the operation screen of the display means 24 or an operation panel to the apparatus to designate a cutting position for cutting the workpiece W. However, with such a designation method, the machine is stopped during the designation and the operating rate is significantly reduced, and the wrong cutting position may be entered due to a wrong alignment reference shape, destroying the workpiece W. There was a problem.

  The present invention has been made for such a problem, and a dicing apparatus and a dicing method capable of preventing an input error in alignment, simplifying an input operation and improving the operation efficiency of the apparatus. The purpose is to provide.

To achieve the above object, the dicing method of the present invention, a dicing apparatus that performs placing the workpiece on a work table, cutting the the work table and the cutting means are relatively moved me by the moving means in the workpiece is imaged by the imaging means is moved by the moving means the placed workpiece table, and automatic recognition method for recognizing I'm the imaged alignment reference which is formed on the workpiece in the image processing method And displaying the alignment target having the same shape as the outer diameter of the alignment reference on the display means and moving the alignment target on the image of the work displayed on the display means, and the alignment reference in the image of the work cutting to cut the work I'm in the use of the manual recognition method to match the the alignment target Together to recognize the location in the dicing device, if it could not recognize the shape of the alignment reference by the automatic recognition method, the position of the workpiece the could not recognize the alignment reference shape, or The imaging position of the workpiece by the imaging means is automatically adjusted by the manual recognition method to the workpiece design position where the alignment reference inputted in advance exists.

According to the dicing method of the present invention, the work table on which the work is placed and the cutting means such as a blade rotated by a spindle or a laser are relatively moved in each direction of XYZθ by the moving means, thereby dicing the work. It will be done.

  The workpiece is picked up by the image pickup means before dicing, and the picked-up image is displayed on the display means, and alignment standards such as streets and fiducial marks are automatically recognized by a known image processing method.

  The alignment reference that could not be recognized by such an automatic recognition method is subsequently input by the manual recognition method after the operator confirms the image of the workpiece displayed on the display means. In the manual recognition method, an alignment target having the same shape as the alignment reference outer diameter formed on the workpiece is read from the storage means and displayed on the display means, and the moving means is operated by an operation button on the display means or an operation panel. Then, the position of the alignment reference is input by relatively moving the work table and the imaging means and aligning the alignment reference that could not be recognized with the alignment target.

In the manual recognition method, the dicing method automatically picks up the workpiece imaging position near the position where it could not be recognized by the automatic recognition method or at a position on the workpiece design where a pre-input alignment reference exists. The operator can quickly confirm the alignment standard to be aligned with the alignment target, and the alignment target has the same shape or part of the shape as the correctly formed alignment standard. It becomes possible to prevent.

  Furthermore, in the present invention, in the manual recognition method, the alignment reference is recognized with a shape recognition reference value that is lower than the shape recognition reference value of the alignment reference used in the image recognition method of the automatic recognition method. It is characterized by doing.

  As a result, when the manual recognition method is performed, image processing is performed with a shape recognition reference value that is lower than the normal shape recognition reference value used in the automatic recognition method, so the alignment target could not be recognized. Even if the alignment reference is not perfectly matched, the shape of the alignment reference is recognized, and the operator can easily perform the alignment work in a short time.

  As described above, according to the dicing apparatus and the dicing method of the present invention, it is possible to prevent input mistakes in alignment, simplify input work, and improve the operation efficiency of the apparatus.

  Hereinafter, preferred embodiments of a dicing apparatus and a dicing method according to the present invention will be described in detail with reference to the accompanying drawings.

  First, the configuration of the dicing apparatus according to the present invention will be described. As shown in FIG. 1, the dicing apparatus 10 is provided with a processing unit 20 having spindles 22 and 22, which are arranged to face each other, with a blade 21 and a wheel cover (not shown) attached to the tip, and a work table 31. In addition to the processing unit, the cleaning unit 52, the load port 51, the transport unit 53, the display unit 24, a controller (not shown), a storage unit, and the like are included.

  As shown in FIG. 2, the processing unit 20 has an X table 33 as a moving means for cutting and feeding the work table 31 in the XX direction in the figure. The work table 31 is moved in the θ direction on the X table 33. A rotating table 32 is provided as a moving means for rotating.

  Further, the processing unit 20 includes Y tables 41 and 41 as moving means for moving in the YY direction of the figure, and moving means for moving in the ZZ direction of the figure provided on each Y table 41 and 41. The Z tables 43 and 43 are provided, and the spindles 22 and 22 to which the blades 21 and 21 as the cutting means attached to the Z tables 43 and 43 and the imaging means 23 such as a microscope are cut and fed in the Z direction. At the same time, the index is fed in the Y direction.

  3 may be attached to the Z tables 43 and 43 as cutting means in place of the spindles 22 and 22 to which the blades 21 and 21 are attached.

  In such a dicing apparatus 10, a circular work or a rectangular work W as shown in FIG. 6 is sucked and placed on the work table 31 for dicing. On the workpiece W, alignment references A1 to A10 are formed that serve as a reference for the cutting position at which the workpiece W is cut into a plurality of chips C by cutting.

  As shown in FIG. 7, the display unit 24 has an operation button for operating the dicing device 10, an image of the workpiece W captured by the imaging device 24, and an alignment reference registered in advance in the storage unit of the dicing device 10. A reference shape B and an alignment target T having the same shape as the reference shape B are displayed.

  Next, the dicing method according to the present invention will be described. In the dicing apparatus 10, the work table 31 and the image pickup means 23 are moved relatively to each other to move the work table 31 and the image pickup means 23 before the dicing is performed by the spindle 22 to which the blade 21 as the cutting means is attached or the laser head 61. 23, and an alignment operation for recognizing the cutting position of the workpiece W by an automatic recognition method for recognizing the shapes of the alignment references A1 to A10 using a known image processing method is performed.

  At this time, if the outer diameter shape is deformed due to a problem in the manufacturing process of the workpiece W, such as the alignment standards A2 and A9, the automatic recognition method cannot recognize the shape, resulting in an error. In such a case, the dicing apparatus 10 has a position on the workpiece that causes an error, a position where a shape closest to the registered shape of the alignment reference exists, or pre-input alignment references A2 and A9 exist. The position on the workpiece W design is stored in a storage means (not shown).

  Subsequently, after the alignment operation of the workpiece W by the automatic recognition method is completed, the position of the alignment reference is input by the manual recognition method so that the dicing apparatus 10 recognizes the accurate position of the alignment reference in error. .

  In the manual recognition method, first, the workpiece W image displayed on the display means 24 moves to an image in the vicinity of the position stored in the storage means when an error is generated by the automatic recognition method.

  An operator operating the dicing apparatus 10 moves the alignment target T read from the storage means and displayed on the display means 24 on the image, and the alignment reference (for example, the alignment reference A2 shown in FIG. A9) and alignment target T are aligned as shown in FIG. The aligned alignment reference is recognized as an alignment reference in the same manner as the alignment reference recognized by the automatic recognition method by the dicing apparatus 10, and the cutting position of the workpiece W is recognized based on the alignment reference.

  Thereby, an input mistake in the position of the alignment reference in the alignment can be prevented, and the input operation can be simplified.

  When the dicing apparatus 10 recognizes the alignment reference by the manual recognition method, when the shape is recognized by using a known image processing method as in the automatic recognition method, the normal recognition method used in the automatic recognition method is used. Image processing is performed with a shape recognition reference value that is lower than the shape recognition reference value. Accordingly, the alignment target T can be recognized without being completely aligned with the alignment references A2 and A9 whose outer diameter shape is deformed, and the operator can easily perform the alignment work in a short time.

  In the dicing apparatus 10 in which all the alignment references A1 to A10 are recognized in this way, the cutting position of the workpiece W is determined based on the position of the alignment reference recognized by both the manual recognition method and the automatic recognition method, and dicing is performed. I will go.

  As described above, according to the dicing apparatus and the dicing method according to the present invention, the alignment target T prevents an input error in alignment and simplifies the input work. As a result, the operation efficiency of the dicing apparatus is improved. It becomes possible to improve.

The perspective view which shows the external appearance of the dicing apparatus which concerns on embodiment of this invention. The perspective view which showed the structure of the process part of the dicing apparatus shown in FIG. The side view which showed the structure of the dicing apparatus which performs dicing with a laser. Side surface sectional drawing which showed the principle of the dicing by a laser. The front view which showed the display screen of the display means. The top view which showed an example of the workpiece | work. The front view which showed the display screen of the display means which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Dicing apparatus, 20 ... Processing part, 21 ... Rotary blade, 22 ... Spindle, 23 ... Imaging means, 24 ... Display means, 31 ... Work table, 32 ... Rotary table, 33 ... X table, 41 ... Y table, 43 ... Z table, 61 ... Laser head, A1 to A10 ... Alignment reference, T ... Alignment target, W ... Workpiece

Claims (2)

In the dicing apparatus placing the workpiece on a work table, for cutting it said the work table and the cutting means are relatively moved me by the moving means,
Imaged by the imaging means is moved by the moving means worktables which the workpiece is placed, and automatic recognition method for recognizing I'm the alignment reference formed captured the workpiece to an image processing technique,
An alignment target having the same shape as the outer diameter of the alignment reference is displayed on the display means, and the alignment target is moved on the image of the workpiece displayed on the display means, and the alignment reference in the image of the workpiece and the alignment reference the cutting position for cutting the workpiece I'm on the use of the manual recognition method to align an alignment target causes recognized by the dicing device,
If the shape of the alignment reference cannot be recognized by the automatic recognition method, there is a position of the workpiece that could not recognize the shape of the alignment reference , or the alignment reference input in advance. A dicing method characterized by automatically aligning the imaging position of the workpiece by the imaging means with the manual recognition method to the position on the workpiece design. In the manual recognition method, the alignment reference is recognized with a shape recognition reference value that is lower than the shape recognition reference value of the alignment reference used in the image recognition method of the automatic recognition method. The dicing method according to claim 1.

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