JP2005219129A - Cutting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device in which an optical means can accurately recognize the state of a workpiece surface without being affected by cutting fluid.
SOLUTION: At least a chuck table 30 for holding a workpiece 12, a cutting means 20 having a cutting blade 22 for cutting the workpiece held on the chuck table, and a workpiece or In a cutting apparatus 10 comprising a cutting fluid supply means for supplying a cutting fluid to a cutting blade and an optical means 60 including a microscope 62 for observing the state of the workpiece before or after cutting, the workpiece The space between 12 and the objective lens 62 a of the microscope 62 is filled with a liquid 90.
[Selection] Figure 2

Description

  The present invention relates to a cutting device, and more particularly, to a cutting device provided with optical means for imaging a workpiece.

  Conventionally, for example, cutting with a cutting blade is performed to divide a semiconductor wafer into chips. Such a cutting apparatus includes, for example, a chuck table that holds a workpiece and a cutting unit that cuts the workpiece held on the chuck table, as disclosed in Patent Document 1. Such cutting means is movable in the Y-axis direction and the Z-axis direction, and the cutting means is provided with a cutting blade capable of rotating at high speed. Further, an optical means having an objective lens is fixed to the side of the cutting means, and the position of the workpiece to be cut can be imaged and detected. The objective lens and the cutting blade are located on the same straight line in the X-axis direction, and the cutting means and the optical means move in conjunction with each other. For this reason, when the position to be cut is detected by taking an image through the objective lens, the position of the cutting blade in the Y-axis direction and the detected position to be cut are automatically aligned. ing.

In the above-described cutting apparatus, the cutting blade is cooled or the contamination that is, for example, cutting waste is washed away by using a cutting fluid. At this time, if water droplets of the cutting fluid remain on the surface of the workpiece, the optical means may misrecognize when imaging the workpiece for the purpose of alignment or kerf check, for example. .

In order to solve such a problem, a method of blowing off the cutting fluid remaining on the surface of the workpiece by air blowing can be considered.

JP-A-7-153719

However, in the method in which the cutting fluid remaining on the surface of the work piece is blown away by air blowing, the surface of the work piece dries quickly, so that the contamination contained in the cutting fluid adheres to the surface. Since the cutting fluid accumulated in the cut grooves and the cutting fluid adhering to the surface irregularities cannot be completely discharged, there is a problem that the problem of erroneous recognition of the workpiece cannot be improved sufficiently.

  Accordingly, an object of the present invention is to provide a new and improved cutting apparatus capable of accurately recognizing the state of the workpiece surface without the optical means being affected by the cutting fluid.

In order to solve the above-mentioned problems, in the first aspect of the present invention, at least a chuck table for holding a workpiece and a cutting blade for cutting the workpiece held on the chuck table are provided. Cutting means; cutting fluid supply means for supplying cutting fluid to the workpiece or the cutting blade during the cutting; and a microscope for observing the state of the workpiece before or after the cutting A space between the workpiece and the objective lens of the microscope is filled with a liquid.
A cutting device is provided.

  In the above-described invention, since the liquid is filled between the objective lens of the microscope of the optical means and the workpiece, water droplets do not exist on the surface of the workpiece. Furthermore, even when contamination is contained in the cutting fluid, it is possible to prevent the contamination from adhering to the surface of the workpiece, so that erroneous recognition of the optical means is reduced. Furthermore, there is an effect that the observation area of the workpiece is enlarged by the liquid lens effect.

  Further, the objective lens of the microscope is provided with an opening in a portion located on the optical axis of the objective lens and a liquid supply port for supplying a liquid into the cover. A cover that covers the entire objective lens is mounted, and the inside of the cover is filled with the liquid by the liquid supplied from the liquid supply port of the cover, and from the opening to the surface of the workpiece. When the liquid is discharged, at least the objective lens of the microscope and the surface of the workpiece are configured to exist in the liquid. The objective lens and the workpiece can be filled with liquid. As a result, there are no water droplets on the surface of the work piece, and even when contamination is contained in the cutting fluid, it is possible to prevent the contamination from adhering to the surface of the work piece. Therefore, erroneous recognition by the optical means is reduced. Furthermore, there is also an effect that the observation area of the workpiece is enlarged by the liquid lens effect.

Further, at least the chuck table and the cutting means are both provided with a water tank present therein, and at least a liquid is supplied to the water tank, and the objective lens of the microscope is submerged in the liquid. If it is configured as described above, not only water droplets can be removed from the surface of the work piece to be observed, but also the contaminants float in a large water tank, so that the contaminants adhere to the surface of the work piece. The possibilities are almost gone. In this way, even if contamination is present in the liquid, it is not optically attached to the surface of the workpiece to be observed, so that it is possible to prevent erroneous recognition of the surface of the workpiece.

Further, if the liquid is configured as a cutting fluid, the liquid used when cutting the workpiece can be used, so that the configuration of the apparatus can be simplified and the processing cost can be reduced. .

In the present invention, since observation is performed by filling a liquid between the objective lens of the microscope of the optical means and the workpiece, there is no water droplet on the surface of the workpiece. Furthermore, even if the contamination is contained in the cutting fluid, it is possible to prevent the contamination from adhering to the surface of the workpiece, so that erroneous recognition by the optical means can be reduced. In addition, there is also an effect that the observation area is enlarged by the liquid lens effect.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

First, based on FIG.1 and FIG.2, the structure of the cutting device concerning 1st Embodiment is demonstrated. FIG. 1 is a perspective view showing the configuration of the cutting apparatus according to the first embodiment. Further, the features of the cutting apparatus according to the present embodiment will be described in detail in order to facilitate understanding by omitting illustration in FIG. 1 and enlarging in FIG.

As shown in FIG. 1, the cutting apparatus according to the present embodiment includes, for example, a chuck table 30 that holds a workpiece 12 such as a semiconductor wafer, and a cutting means that cuts the workpiece 12 held on the chuck table 30. 20, a cutting means moving means for moving the cutting means 20 in, for example, the Y-axis and Z-axis directions, a chuck table moving means for moving the chuck table 30 in, for example, the X-axis direction, and a workpiece or a cutting blade at the time of cutting An optical means 60 comprising a cutting fluid supply nozzle 28 for supplying a cutting fluid, an imaging means (reference numeral 64 in FIG. 2) for imaging the surface of the workpiece, and a microscope (reference numeral 62 in FIG. 2); In order to fill the space between the objective lens of the microscope (reference numeral 62a in FIG. 2) and the workpiece 12 with a liquid (for example, cutting fluid), at least the entire objective lens is covered. Consisting of cover 70..

  The chuck table 30 includes, for example, a vacuum chuck mechanism on the upper surface thereof, and can hold the workpiece 12 by vacuum suction. Further, the chuck table 30 can be rotated in the horizontal direction by an electric motor (not shown) while holding the workpiece 12, for example.

  Below the chuck table 30, chuck table moving means is provided. The chuck table moving means is, for example, disposed on the chuck support member 32 that supports the chuck table 30 substantially horizontally and on the base 39 so as to extend in the X-axis direction. And a pair of first guide rails 34 for guiding the movement of the chuck table and the X-axis direction. The first guide rail 34 engages with the lower portion of the chuck table support member 32 and is driven to rotate by the first electric motor 38. And a first ball screw 36. The chuck table moving means rotates the first ball screw 36 and moves the chuck table support member 32 along the first guide rail 34 in the X-axis direction, thereby moving the chuck table 30 and the workpiece 12 together. It can be moved in the X-axis direction.

  On the other hand, the cutting means 20 is disposed, for example, so as to be positioned above the chuck table 30. The cutting means 20 includes, for example, an extremely thin cutting blade 22 having a substantially ring shape, and a rotary shaft arranged to extend in the Y-axis direction. A spindle 24 that rotates at high speed by an electric motor 23 that is driving means connected to the unit, and a spindle housing 26 that rotatably supports the spindle 24 are provided. The cutting means 20 forms a very thin kerf by cutting the workpiece 12 in the X-axis direction by cutting the workpiece 12 while rotating the cutting blade 22 at a high speed by the rotational driving force of the spindle 24. can do. The “axial direction of the spindle” according to the present embodiment is the Y-axis direction, and is perpendicular to both the moving direction (X-axis direction) and the vertical direction (Z-axis direction) of the chuck table 30 that are cutting directions. Direction.

  Further, for example, a cutting means moving mechanism is provided on one side of the cutting means 20. This cutting means moving mechanism generally includes, for example, a suspension part 40 that suspends the cutting means 20, a suspension part support means that includes a support member 50 and a second guide rail 54, and a first part. And a drive mechanism including a ball screw 56 and a second electric motor 58.

  More specifically, the support member 50 is, for example, a gate-shaped metal plate-like member disposed so as to stand substantially vertically. That is, the support member 50 includes, for example, a beam portion 51 disposed so as to extend substantially in the Y-axis direction and two beams that are disposed so as to extend in the Z-axis direction and support both ends of the beam portion 51. It consists of a column 52. The beam portion 51 extends forward in the Y-axis direction (on the front side of the apparatus) so as to cross the upper portion of the first guide rail 34 of the chuck table moving means. In this beam portion 51, the Y-axis position of the end portion on the front side of the apparatus is substantially the same as the Y-axis position of the end portion on the front side of the chuck table 30 (front side in the Y-axis direction), for example. Compared to the front side of the device, it does not protrude excessively.

  The support member 50 includes, for example, a pair of second guide rails 54 that guide the movement of the cutting means 20, the optical means 60, and the suspension portion 40 in the Y-axis direction, the cutting means 20, the optical means 60, and the like. A second electric motor 58 and a second ball screw 56, which are drive mechanisms for moving the suspension portion 40 in the Y-axis direction, are disposed. The second ball screw 56 is engaged with the supported member 42 of the suspension portion 40 and is driven to rotate by the second electric motor 58. Further, the support member 50 and the second guide rail 54 can support the suspension part 40 so as to be movable in the Y-axis direction. The support member 50, the second guide rail 54, and the drive mechanism having such a configuration are configured by rotating the second ball screw 56 and moving the suspension portion 40 along the second guide rail 54 in the Y-axis direction. The cutting means 20 suspended by the suspension part 40 can be moved in the Y-axis direction so that the cutting edge position of the cutting blade 22 and the cutting line of the workpiece 12 can be aligned.

  The suspension unit 40 has, for example, a function of suspending the cutting means 20 from above and a function of moving the cutting means 20 in the Z-axis direction. More specifically, the suspension portion 40 is connected to, for example, the spindle housing 26 of the cutting means 20 and is supported by a suspension member 41 that suspends the cutting means 20 and the second guide rail 54. A support member 42, a supported member 42, a pair of third guide rails 44 for guiding the movement of the suspension member 41 and the cutting means 20 in the Z-axis direction, and the supported member 42; It comprises a third electric motor 48 and a third ball screw 46 which are drive mechanisms for moving the cutting means 20, the optical means 60, and the suspension member 41 in the Z-axis direction.

  The suspension member 41 may, for example, suspend a region including the center of gravity of the cutting means 20 to maintain the balance of the cutting means 20, or suspend a portion close to the cutting blade 22 of the cutting means 20. It is also possible to effectively suppress bending and vibration of the spindle 24 closer to the cutting blade 22 than the suspended portion. The third ball screw 46 is engaged with the suspension member 41, supports the suspension member 41, and is rotationally driven by the third electric motor 48 to move the suspension member 41 in the Z-axis direction. Can be moved.

  The suspension unit 40 having such a configuration rotates the third ball screw 46 to move the suspension member 41 along the third guide rail 44 in the Z-axis direction, thereby causing the cutting unit 20 and the optical unit 60 to move. The cutting depth of the cutting blade 22 relative to the workpiece 12 can be adjusted by moving in the Z-axis direction.

The optical means 60 is fixed to the spindle housing 26 as shown in FIGS. 1 and 2, and is interlocked with the movement of the spindle housing 26. The optical means 60 includes a microscope 62 and an imaging means (for example, a CCD camera) 64, and the microscope 62 includes an objective lens 62a. The imaging unit 64 and the microscope 62 are incorporated on the same axis, and the kerf formed by the rotating blade is captured by the microscope 62 and captured by the imaging unit 64. With this configuration, the position to be cut of the workpiece 12 can be imaged and detected. The objective lens 12 and the cutting blade 22 are located on the same straight line in the X-axis direction, and the cutting means 20 and the optical means 60 move in conjunction with each other. For this reason, when a position to be cut is detected by imaging through the objective lens 62a, the position of the cutting blade 22 in the Y-axis direction and the detected position to be cut are automatically aligned. It is configured.

Further, as shown in an enlarged view of the characteristic part of the cutting apparatus according to the present embodiment in FIG. 2, unlike the conventional case, the cutting fluid is interposed between the objective lens 62 a of the microscope 62 of the optical means 60 and the surface of the workpiece 12. In order to fill the liquid 90 such as the above, a cover 70 that covers at least the objective lens 62a of the microscope 62 of the optical means 60 is formed. The cover 70 is provided with an opening 72a in a portion on the optical axis of the objective lens 62a. Further, a liquid 90 such as a cutting fluid (for example, pure water) is provided on a side surface of the cover 70 from a liquid supply pipe 74. Is provided with a liquid supply port 72b. Further, the liquid supply pipe 74 is connected to a cutting fluid storage means for storing the cutting fluid supplied to the cutting fluid supply nozzle 28 via, for example, a tube, and from the cutting fluid storage means via the tube and the liquid supply piping 74. Then, the cutting fluid is supplied into the cover 70 from the liquid supply port 72b. The cutting fluid 90 supplied from the liquid supply port 72b is discharged from the opening 72a after filling the cover interior 70. At this time, the water pressure is adjusted so that at least the objective lens 62 a of the microscope 62 and the surface of the workpiece 12 are always filled with the cutting fluid 90.

In this embodiment, water droplets can be eliminated from the surface of the workpiece to be observed, and the workpiece surface in front of the objective lens is cleaned with a liquid (for example, a cutting fluid). Can be observed well. Further, by using the cutting fluid used when cutting the workpiece, the configuration of the apparatus can be simplified, and the processing cost can be reduced.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

In the above embodiment, the configuration in which liquid is filled in the cover formed around the objective lens has been described as an example, but the present invention is not limited to this example. This can be done if the surface of the workpiece and the objective lens are immersed in water.

For example, as shown in FIG. 3, a water tank 80 for filling a liquid 90 such as a cutting fluid is provided between the objective lens 62a of the microscope 62 of the optical means 60 and the surface of the workpiece 12, and the chuck table 30 is provided. Alternatively, the entire cutting means 20 may be submerged. According to such a configuration, not only water droplets can be eliminated from the surface of the workpiece 12 to be observed, but also the contaminants float in the liquid 90 of the large water tank 80, so that contamination is present on the surface of the workpiece 12. Almost no adhesion. In this way, even if contamination is present in the liquid, since it is not optically attached to the surface of the workpiece 12 to be observed, erroneous recognition of the surface of the workpiece 12 is prevented.

Moreover, in the said embodiment, although the structure which used liquids, such as a cutting fluid, was mentioned as an example between the surface of a to-be-processed object and the objective lens of a microscope, it demonstrated, It is not limited to this example. Other liquids can be used as long as they are transparent.

In the above embodiment, an example in which an optical unit including one microscope and an imaging unit is employed has been described. However, the present invention is not limited to this example. It is also possible to install microscopes having a plurality of different magnifications. For example, two sets of microscopes (for example, two microscopes having different magnifications, such as one microscope having a magnification of 5 times and the other microscope having a magnification of 50 times) can be used. In this case, for example, after performing rough alignment with a low magnification microscope, accurate alignment can be performed with a high magnification microscope.

  The present invention can be applied to a cutting apparatus, and more specifically, can be applied to a cutting apparatus having an optical means for observing the surface of a workpiece.

It is a perspective view which shows the structure of the cutting device concerning 1st Embodiment. It is sectional drawing which shows the structure of the cover provided in the circumference | surroundings of the optical means of the cutting device concerning 1st Embodiment. It is sectional drawing which shows the structure of the water tank provided in the circumference | surroundings of the chuck table of the cutting device concerning other embodiment, an optical means, and the cutting means.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cutting device 12 Workpiece 20 Cutting means 22 Cutting blade 24 Spindle 28 Cutting fluid supply nozzle 30 Chuck table 40 Suspension part 50 Support member 51 Beam part 52 Supporting part 54 Second guide rail 56 Second ball screw 58 Second 2 Electric motor 60 Optical means 62 Microscope 62a Objective lens 64 Imaging means 72 Cover 72a Opening 72b Liquid supply part 74 Piping 80 Water tank 90 Liquid (for example, cutting fluid)

Claims (4)

At least a chuck table for holding a workpiece, a cutting means including a cutting blade for cutting the workpiece held on the chuck table, and the workpiece or the cutting blade at the time of the cutting. A cutting apparatus comprising: a cutting fluid supply means for supplying a cutting fluid; and an optical means including a microscope for observing the state of the workpiece before or after the cutting.
The space between the workpiece and the objective lens of the microscope is filled with liquid,
The cutting device characterized by the above-mentioned. The objective lens of the microscope covers the entire objective lens of the microscope having an opening provided in a portion located on the optical axis of the objective lens and a liquid supply port for supplying a liquid into the cover. A cover is attached,
The inside of the cover is filled with the liquid by the liquid supplied from the liquid supply port of the cover, and the liquid is discharged from the opening to the surface of the workpiece, thereby at least the microscope. The objective lens and the surface of the workpiece are configured to exist in a liquid,
The cutting apparatus according to claim 1. At least a water tank is installed so that both the chuck table and the cutting means exist in the interior,
The cutting apparatus according to claim 1, wherein at least the objective lens of the microscope is submerged in a liquid supplied to the water tank. The cutting device according to claim 1, wherein the liquid is a cutting fluid.

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