JP2007288010A - Sheet cutting device and cutting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To cut a sheet in accordance with the size of a planar member, with the sheet affixed thereto whose size exceeds a circumference of the planar member such as a wafer. <P>SOLUTION: A sheet cutting device 10 that cuts the sheet S whose size exceeds the circumference of a semiconductor wafer W with a cutter blade 12 along the circumference of the semiconductor wafer W after affixing the sheet S to the semiconductor wafer W. The cutting device 10 includes an imaging camera 30 that images a circumferential shape of the semiconductor wafer W, and determines a moving locus of the cutter blade 12 based on the imaged data, and the sheet S is cut by moving the cutter blade 12 along the moving locus through a robot 11. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sheet cutting apparatus and a cutting method, and more specifically, after a sheet having a size protruding from the outer periphery of the plate member is attached to the plate member, the sheet is cut along the outer periphery of the plate member. The present invention relates to a sheet cutting apparatus and a cutting method capable of performing the above.

  2. Description of the Related Art Conventionally, a protective sheet for protecting a circuit surface serving as a surface of a semiconductor wafer (hereinafter simply referred to as “wafer”) has been applied.

  Since the wafer with the protective sheet is subjected to back-grinding (back grinding) in the subsequent process, when the protective sheet is applied, it is cut so that it does not protrude from the outer periphery of the wafer and the sheet is rolled up during back-grinding. It is required to prevent the wafer from being damaged. Therefore, in Patent Document 1, a cutter blade having a center of rotation is provided on the vertical line at the top of the wafer, and the sheet stuck out of the outer periphery of the wafer by rotating the cutter blade in a plane is formed into a wafer shape. A sheet cutting apparatus and a cutting method for cutting together are disclosed.

JP-A-2005-19841

However, in the sheet cutting apparatus disclosed in Patent Document 1, since the cutter blade rotates around the rotation center axis on the wafer, alignment for performing alignment between the wafer center and the rotation center is performed. The apparatus becomes an indispensable component of the sheet cutting apparatus, and there is a disadvantage that the processing time required for alignment and the total time until the sheet cutting is completed become longer and the cutting efficiency is lowered. In addition, when the alignment device generates an error for some reason, the error appears as a deviation between the center of the wafer and the rotation center of the cutter blade, and the cutter blade hits the outer periphery of the wafer and damages the wafer or the cutter blade. Invite the problem of
In addition, the sheet sticking object is limited to a circular one like a wafer, and can not cope with cutting when a sheet is stuck on a sticking object having a planar shape such as a polygon or an ellipse other than that, There is also an inconvenience.

[Object of invention]
The present invention has been devised by paying attention to such inconveniences, and the object of the present invention is to attach the sheet having a size protruding from the outer periphery of a plate member such as a wafer to the plate member. Is to provide a sheet cutting device and a cutting method that can cut the sheet in accordance with the shape of the plate member.
Another object of the present invention is to eliminate the need for an alignment device for accurately positioning the plate-like member, to improve sheet cutting efficiency, and to limit the planar shape of the plate-like member. It is an object of the present invention to provide a sheet cutting apparatus and a cutting method that are not required.

In order to achieve the above object, the present invention cuts the sheet along the outer periphery of the plate-like member through a cutter blade after a sheet having a size protruding from the outer periphery of the plate-like member is attached to the plate-like member. In the sheet cutting device,
Including imaging means for imaging the outer peripheral shape of the plate-like member;
A configuration is adopted in which the cutter blade is provided so as to be able to operate in a predetermined manner according to a movement trajectory based on imaging data of the imaging means, and the sheet is cut.

  In the present invention, the plate-like member may have a configuration in which the planar shape is substantially circular, and the cutter blade is rotatably provided with the center of the plate-like member obtained by the imaging means as a rotation center. .

  Moreover, it is preferable that the said imaging means shall be equipped with the function to detect whether the actual cutting locus of the said cutter blade has shifted | deviated with respect to the said movement locus | trajectory.

  Furthermore, the cutter blade can be configured to be supported by an articulated robot that is numerically controlled.

  The cutter blade can be provided so that a toe-in angle, a camber angle, and a caster angle can be adjusted during cutting.

  Further, the imaging means further has a blade edge inspection function for inspecting the tip side of the cutter blade, and is provided so as to perform a blade edge inspection when the sheet cutting operation is completed and / or before the sheet cutting operation. Good.

  Moreover, when the change in the length of the cutter blade is detected by the blade edge inspection function, the insertion depth of the cutter blade can be adjusted according to the amount of change.

  Furthermore, the imaging means can be constituted by an infrared camera.

  Further, a configuration may be adopted in which a table that supports the plate member is included and the plate member is heated by a heating means.

Furthermore, the present invention provides a sheet cutting method for cutting the sheet along the outer periphery of the plate-like member via a cutter blade after a sheet having a size protruding from the outer periphery of the plate-like member is attached to the plate-like member.
A method is adopted in which the outer peripheral shape of the plate-like member is imaged by an imaging means, and the cutter blade is moved in accordance with a movement locus based on imaging data of the imaging means to cut the sheet.

  In the cutting method, when the planar shape of the plate-like member is substantially circular, the imaging means obtains the center of the plate-like member, and then performs the cutting by rotating the cutter blade around the center. be able to.

According to the present invention, the movement trajectory of the cutter blade can be determined based on the imaging data, and the cutting of the sheet is accurately performed according to the shape of the plate member by the movement of the cutter blade according to the movement trajectory. It becomes possible. In addition, since it is not necessary to position the plate-shaped member using the alignment device, it is possible to reduce the essential configuration of the device and omit the time required for alignment, and it is not subject to the restriction of the planar shape of the plate-shaped member. Generality can be imparted.
Furthermore, when the planar shape of the plate-like member is substantially circular, the movement locus can be easily determined by obtaining the center thereof.
In addition, if the imaging means detects the deviation between the cutting position of the cutter blade and the movement trajectory based on the imaging data, if the cutter blade cannot be cut accurately for some reason, the cutting operation is stopped, etc. Necessary measures can be taken, and it becomes possible to prevent the occurrence of defective products.
Further, when the cutter blade holding means is constituted by an articulated robot that is numerically controlled, it is possible to perform sheet cutting with a complicated planar shape by adding diversity to the movement trajectory of the cutter blade. .
Also, if the cutter blade is provided with adjustable toe angle, camber angle, and caster angle at the time of cutting, it is possible to cut the sheet under optimum conditions by adjusting these according to the thickness, rigidity, etc. of the sheet It becomes.
Furthermore, in the configuration that can inspect the blade edge of the cutter blade, if the cutter blade breaks or wears and changes its length, the cutting depth can be reduced by adjusting the depth of insertion of the cutter blade thereafter. It can be avoided.
Moreover, by imaging using an infrared camera, it is possible to cope with the case where an opaque sheet is stuck on the plate-like member, and further, the plate-like member can be imaged more clearly by heating the support table. .

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a sheet cutting apparatus 10 according to the present embodiment, and a wafer W as a plate-like member that is provided in the sheet cutting apparatus 10 and has a substantially circular planar shape, and supports the wafer substantially horizontally. The schematic front view of the table T which affixes the protective adhesive sheet S on the upper surface (circuit surface) of W is shown. In this figure, the sheet cutting device 10 is configured to include a robot 11, a cutter blade 12 held by the robot 11, and an imaging means 13 attached to the robot 11.

  The robot 11 includes a base portion 14, first arm 15 </ b> A to sixth arm 15 </ b> F disposed on the upper surface side of the base portion 14 and provided to be rotatable in the directions of arrows A to F, and the tip of the sixth arm 15 </ b> F. And a tool holding chuck 19 attached to the free end side of the robot 11. The second, third, and fifth arms 15B, 15C, and 15E are rotatably provided in the Y × Z plane in FIG. 1, and the first, fourth, and sixth arms 15A, 15D, and 15F are It is provided so as to be rotatable around its axis. The robot 11 in this embodiment is controlled by numerical control. That is, the amount of movement of each joint relative to the workpiece (wafer W) is controlled by numerical information corresponding to each, and the amount of movement is all controlled by a program, and the wafer size is the same as in a conventional cutting apparatus. The method uses a completely different method from the method in which the position of the cutter blade is manually changed every time the change is made. Further, in the conventional cutting apparatus, it has been necessary to readjust the cutting diameter each time in accordance with the change in the posture of the cutter blade (toe angle α1, camber angle α2, caster angle α3, which will be described later). No. 11 can maintain the cutting diameter at a set value with high accuracy, no matter how the posture of the cutter blade is changed.

  As shown in FIG. 2, the tool holding chuck 19 is arranged at a position spaced apart from the cutter blade receiver 20 having a substantially cylindrical shape by an interval of about 120 degrees in the circumferential direction of the cutter blade receiver 20. And three chuck claws 21 that detachably hold 12. Each chuck claw 21 is formed as a pointed portion 21A having an acute inward end, and can be advanced and retracted in the radial direction with respect to the center of the cutter blade receiver 20 by air pressure.

  As shown in FIG. 3, the cutter blade 12 includes a blade holder 12A that forms a base region, and a blade 12B that is detachably fixed to the distal end side of the blade holder 12A. The blade holder 12A has a substantially cylindrical shape, and grooves 22 are formed along the axial direction on the base end side of the outer peripheral surface at positions spaced at an interval of about 120 degrees in the circumferential direction. By engaging the portion 21A, the position of the cutter blade 12 with respect to the tool holding chuck 19 is kept constant.

The imaging means 13 is constituted by an imaging camera 30, and imaging data of the imaging camera 30 is output to a controller (not shown). As shown in FIG. 1, the imaging camera 30 is positioned above the cutter blade 12 at a predetermined position, and the tool holding chuck 19 so that the sheet S and the wafer W are positioned below the cutter blade 12. Is supported by a bracket 31 attached to the outer periphery of the bracket. The sheet S in the present embodiment is transparent or translucent, so that the outer peripheral edge position of the wafer W can be imaged even if the wafer W is positioned on the lower surface side of the sheet S. It has become. As shown in FIG. 4, the imaging camera 30 captures the tip region of the blade 12 </ b> B, the sheet S positioned below this, and a partial region of the wafer W as an imaging area, and outputs the imaging data to the controller. . Then, the outer peripheral position of the wafer W is specified by performing image processing on the imaging data with the controller, and the movement locus by the blade 12B is determined. Thereby, the controller moves the cutter blade 12 according to the movement locus. Controls the robot 11 in a predetermined manner.
Further, the controller that processes the imaging data of the imaging camera 30 uses the intersection point of the vertical bisectors a and b of the two strings A and B as the center C of the wafer W, as shown in FIG. And a function of outputting a signal for operating the robot 11 with the center C as the rotation center of the blade 12B.
Further, the imaging means 13 detects whether or not the actual cutting locus of the blade 12B is deviated from the movement locus determined by the image processing (see FIG. 4C), and when the deviation is detected. In addition, it is configured to have a function of stopping the operation of the entire apparatus or notifying a predetermined alarm.

  As shown in FIGS. 1 and 2, the cutter blade 12 is configured so that the tip end side of the blade 12B is inspected by the blade edge inspection function of the imaging means 13 after the cutting operation is completed or before the cutting operation is performed. Is also configured. The imaging camera 30 images the tip region of the blade 12B, outputs the imaged data to the controller, performs image processing with the controller, and changes the length of the blade 12B with respect to the reference length and the edge shape with respect to the blade edge reference shape. Changes are detected. And when detecting the change shortened by the tip of the blade 12B being bent or worn, the robot 11 adjusts the insertion depth at the next cutting so as to complement the amount of change, Thereby, the insertion depth of the cutter blade 12 is not insufficient. Further, when it is determined that the blade 12B has been shortened by the inspection, the sheet S cut immediately before may not be completely cut, so a signal is output to the outside so as to inspect the sheet S. It can be done. When damage to the blade edge is detected, the insertion depth can be changed and cutting can be performed in a normal blade edge region, or the robot 11 can be switched to another new cutter blade 12.

As shown in FIG. 1, the table T includes an outer table 41 having a substantially square shape in a plan view and an inner table 42 having a substantially circular shape in a plan view. The outer table 41 is provided in a concave shape capable of receiving the inner table 42 in a state where a gap is formed between the outer table 41 and the outer edge of the inner table 42, and can be moved up and down with respect to the base 45 via the single-axis robot 44. Is provided. On the other hand, the inner table 42 is provided so as to be movable up and down with respect to the outer table 41 via a single-axis robot 46. Therefore, the outer table 41 and the inner table 42 can be moved up and down integrally, and can be moved up and down independently of each other, whereby a predetermined height position is set according to the thickness of the sheet S and the thickness of the wafer W. Can be adjusted.

  A sheet feeding unit (not shown) for feeding the sheet S onto the wafer W is arranged on the upper side of the table T. The sheet S fed from the sheet feeding unit onto the wafer W is not shown. The bonding roller moves in the sheet feeding direction while rotating on the sheet S, whereby the sheet S is bonded to the upper surface of the wafer W.

  Next, a method for cutting the sheet S in the present embodiment will be described with reference to FIGS. The sheet S is affixed to the wafer W in the manner disclosed in Japanese Patent Application No. 2005-198806.

  As an initial setting, as shown in FIG. 5, the toe-in angle α1 in which the center line of the cutter blade 12 is inclined with respect to the cutting direction along the outer periphery of the wafer W in the top view of the cutting direction, as shown in FIG. The camber angle α2 in which the center line of the cutter blade 12 is inclined when viewed in the front direction, and the caster angle α3 in which the center line of the cutter blade 12 is inclined in the cutting direction in the side view of the cutting direction as shown in FIG. Is done. The reason for setting such toe-in angle α1, camber angle α2, and caster angle α3 is to enable cutting under optimum conditions according to the thickness, rigidity, etc. of sheet S.

  First, the sheet cutting device 10 performs an operation of removing the cutter blade 12 from the tool holding chuck 19 and moving it to a suction arm (not shown) to temporarily act as a transfer device, taking out the wafer W from a wafer cassette (not shown), Place on table T. Regarding the placement of the wafer W, since the wafer cassette has a predetermined dimensional accuracy, the wafer W can be positioned so that the outer periphery of the wafer W fits in the gap between the outer table 41 and the inner table 42.

  Subsequently, the sheet S is attached to the upper surface side of the wafer W. While this sticking operation is being performed, the sheet cutting device 10 performs an operation of switching from the suction arm to the cutter blade 12. After the application of the sheet S is completed, the cutter blade 12 and the imaging camera 30 are positioned at a predetermined position above the table T as shown in FIG. The image data of the imaging camera 30 at that time is shown in FIG. The lowering amount of the cutter blade 12 is determined by the initial setting, and the point at which the sheet S is cut by the blade 12B is the intersection of the reference lines LX and LY provided in the imaging camera 30 shown in FIG. Is set. Therefore, when the cutter blade 12 is lowered so that the outer periphery of the wafer W matches the intersection of the reference lines LX and LY, the blade 12B is inserted into the sheet S by a predetermined amount as shown in FIG. Become.

  Next, in the state shown in FIG. 4B, the rotation center C of the cutter blade 12 and the diameter of the wafer W are obtained by the above-described strings A and B, thereby determining the movement locus of the blade 12B at the time of cutting. The

With the movement trajectory determined in this way, the cutter blade 12 cuts the sheet S along the outer periphery of the wafer W according to the movement trajectory in which the rotation center C is the rotation center of the cutter blade 12. . While this cutting operation is performed, the imaging camera 30 continuously determines whether or not the actual cutting locus of the cutter blade 12 is deviated from the movement locus, as shown in FIG. When the deviation is detected, a predetermined signal is output to stop the cutting operation, or an alarm is issued to perform a required inspection operation.
The V notch region indicating the crystal orientation of the wafer W can be dealt with by taking in real-time imaging data from the imaging camera 30 and creating correction data, and the controller outputting the correction data to the robot 11. At this time, the insertion depth of the blade 12B is displaced so as to be relatively shallow, so that cutting can be accurately performed even in a minimal area such as a V notch.

  After the cutting of the sheet S is completed, the cutter blade 12 returns to a predetermined standby position and undergoes a blade edge inspection. Similarly to the above, the sheet cutting apparatus 10 temporarily changes to a suction arm (not shown), holds the wafer W by suction, and stores it in a wafer cassette (not shown). On the other hand, the outer unnecessary sheet portion generated by the cutting is wound up by a winding device (not shown). Thereafter, the next wafer W is transferred onto the table T again by the suction arm held by the sheet cutting apparatus 10, and thereafter the cutting operation is performed in the same manner.

  Therefore, according to such an embodiment, the effect that the sheet S can be cut according to the outer peripheral shape of the wafer W without performing alignment of the wafer W is obtained.

As described above, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this.
In other words, the present invention has been illustrated and described mainly with respect to specific embodiments, but without departing from the scope of the technical idea and object of the present invention, the shape, position, or With respect to the arrangement and the like, those skilled in the art can make various changes as necessary.

For example, in the above embodiment, the case where the sheet S is transparent or translucent has been described.
In the case of a sheet that transmits a specific wavelength, an imaging camera that can recognize the wavelength may be used. That is, if the sheet S is infrared transmissive, if the imaging camera 30 is an infrared camera, the outer peripheral position of the wafer W located on the lower surface side of the sheet S can be imaged even if the sheet S is opaque. Thus, substantially the same cutting can be performed.

  Furthermore, it is good also as a structure which incorporates the coil as an overheating means in the inner side table 42 of the table T which supports the wafer W. FIG. With this configuration, the wafer W can be imaged more clearly during imaging by the infrared camera.

  In addition, the plate-like member is not limited to the semiconductor wafer W, and other plate-like members such as glass, a steel plate, or a resin plate can be targeted. The semiconductor wafer can be a silicon wafer or a compound wafer. It may be. Further, the planar shape of the plate-like member is not limited to a substantially circular shape, and may be various planar shapes such as an ellipse and a polygon.

  Furthermore, although the case where the sheet | seat S was affixed on the substantially circular wafer W and cut | disconnected along the outer periphery of the wafer W was shown in the said embodiment, the plate-shaped member provided with planar shapes other than circular may be sufficient. . In this case, in addition to the method of determining and cutting the movement locus while capturing the imaging data from the imaging camera 30 in real time, the movement locus is determined in advance based on the imaging data covering the entire area of the plate member and cutting is performed. Of course it is possible.

1 is a schematic front view of a sheet cutting device and a table according to the present embodiment. The expansion perspective view which shows the front end side area | region of a robot. The expansion perspective view of a cutter blade. (A) is a schematic plan view taken by the imaging camera when the cutter blade and the imaging camera are positioned at a predetermined position above the table T, (B) is a schematic plan view showing a state where a predetermined amount of the blade is inserted, C) is a schematic plan view showing a state in which a sheet is cut with a cutter blade. Operation | movement explanatory drawing which cut | disconnects a sheet | seat, keeping a toe-in angle. Explanatory drawing of operation | movement which cut | disconnects a sheet | seat maintaining a camber angle | corner. Operation | movement explanatory drawing which cut | disconnects a sheet | seat, maintaining a caster angle.

Explanation of symbols

10 Sheet cutting device 11 Robot (holding means)
12 cutter blade 12B blade 30 imaging camera (imaging means)
S sheet W Semiconductor wafer (plate-like member)

Claims (11)

In a sheet cutting device that cuts the sheet along the outer periphery of the plate member via a cutter blade after a sheet having a size protruding from the outer periphery of the plate member is attached to the plate member,
Including imaging means for imaging the outer peripheral shape of the plate-like member;
A sheet cutting apparatus characterized by cutting the sheet by providing the cutter blade in a predetermined operation according to a movement trajectory based on imaging data of the imaging means. The planar shape of the plate-like member is substantially circular, and the cutter blade is rotatably provided with the center of the plate-like member obtained by the imaging means as a rotation center. Sheet cutting device. The sheet cutting apparatus according to claim 1, wherein the imaging unit has a function of detecting whether or not an actual cutting locus of the cutter blade is deviated from the movement locus. 4. The sheet cutting apparatus according to claim 1, wherein the cutter blade is supported by an articulated robot that is numerically controlled. The sheet cutter according to any one of claims 1 to 4, wherein the cutter blade is provided so that a toe-in angle, a camber angle, and a caster angle can be adjusted during cutting. The imaging means further has a blade edge inspection function for inspecting the tip side of the cutter blade, and performs the blade edge inspection when the sheet cutting operation is completed and / or before the sheet cutting operation. The sheet cutting device according to any one of claims 1 to 5. The sheet cutting device according to claim 6, wherein when a change in the length of the cutter blade is detected by the blade edge inspection function, the insertion depth of the cutter blade is adjusted according to the change amount. The sheet cutting apparatus according to claim 1, wherein the imaging unit is configured by an infrared camera. The sheet cutting apparatus according to claim 1, further comprising a table that supports the plate-like member, wherein the plate-like member is heated by a heating unit. In the sheet cutting method of cutting the sheet along the outer periphery of the plate member through a cutter blade after pasting the sheet of a size protruding from the outer periphery of the plate member to the plate member,
A sheet cutting method characterized in that the outer peripheral shape of the plate-like member is imaged by an imaging means, and the cutter blade is moved according to a movement locus based on imaging data of the imaging means to cut the sheet. When the planar shape of the plate-like member is substantially circular, the center of the plate-like member is obtained by the imaging means, and then the cutting is performed by rotation of a cutter blade with the center as a rotation center. The sheet cutting method according to claim 8.

Images