JP6770902B2 - Processing method of work piece - Google Patents

Description

The present invention relates to a method for processing a workpiece.

Problems such as chipping of the edge of the work piece after thinning or peeling of the edge of the work piece joined to the substrate when performing a process of forming a film on the work piece in the process after thinning. was there. Therefore, conventionally, the cutting blade is cut by positioning the cutting blade in the tangential direction of the disk-shaped workpiece, that is, at a position where the cutting direction of the cutting blade and the tangent of the peripheral edge of the workpiece are 0 degrees. However, edge trimming was performed by rotating the workpiece to remove the outer peripheral portion (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2016-2623

When a wafer containing copper or a wafer having a thick oxide film on the device surface to be processed is edge-trimmed by the conventional method shown in Patent Document 1, fine chipping occurs in the vicinity of the device region. The fine chipping may cause scratches on the device surface after joining the wafers in the subsequent process.

The present invention has been made in view of such a point, and an object of the present invention is to provide a method for processing a workpiece capable of suppressing the occurrence of chipping.

In order to solve the above-mentioned problems and achieve the object, the processing method of the workpiece of the present invention removes the area to be removed on the outer periphery of the disk-shaped workpiece having a plurality of devices formed on the surface. A method of machining a work piece, the first positioning step of positioning the cutting direction of the cutting blade in the tangential direction of the peripheral edge of the work piece, and the work piece while cutting the cutting blade into the work piece. Position the cutting blade at an angle where the first cutting step of rotating the object to remove the first planned removal area and the cutting direction of the cutting blade and the tangent line of the peripheral edge of the workpiece exceed 0 degrees. The second positioning step includes a second positioning step and a second cutting step of rotating the workpiece while cutting the cutting blade into the workpiece to remove the second planned removal region. The planned removal area includes an area closer to the device area than the first planned removal area.

The processing method of the workpiece of the present invention is a processing method of the workpiece that removes the area to be removed on the outer periphery of the disk-shaped workpiece, and is a method of processing the cutting blade and the peripheral edge of the workpiece. The first positioning step of positioning the cutting blade at an angle where the tangent line exceeds 0 degrees, and the first planned removal area by rotating the work piece while cutting the cutting blade from the surface of the work piece. The first cutting step of removing the cutting blade, the second positioning step of positioning the cutting direction of the cutting blade in the tangential direction of the peripheral edge of the workpiece, and the rotation of the workpiece while cutting the cutting blade. It is characterized by including a second cutting step of removing the second planned removal region, and the first planned removal region includes a region closer to the device region than the second planned removal region. ..

The angle exceeding 0 degrees is preferably 5 degrees or more.

The angle exceeding 0 degrees is preferably 90 degrees.

Therefore, in the processing method of the workpiece of the present invention, chipping at the time of edge trimming is performed by positioning the cutting direction and the tangent line of the peripheral edge of the workpiece at an angle exceeding 0 degrees in a region closer to the device region. Can be suppressed.

FIG. 1 is a perspective view showing an example of a work piece to be processed in the work piece processing method according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a flowchart showing the flow of the processing method of the workpiece according to the first embodiment. FIG. 4 is a perspective view showing a configuration example of a cutting device used in the method for processing a workpiece according to the first embodiment. FIG. 5 is a plan view showing a first positioning step of the work piece processing method according to the first embodiment. FIG. 6 is a side view showing a first cutting step of the work piece processing method according to the first embodiment. FIG. 7 is a side sectional view showing a work piece after the first cutting step of the work piece processing method according to the first embodiment. FIG. 8 is a plan view showing a second positioning step of the work piece processing method according to the first embodiment. FIG. 9 is a side view showing a second cutting step of the work piece processing method according to the first embodiment. FIG. 10 is a side view showing a first planned removal region and a second planned removal region of the work piece processing method according to the first embodiment. FIG. 11 is a side sectional view showing a work piece after the second cutting step of the work piece processing method according to the first embodiment. FIG. 12 is a side sectional view showing a state in which a substrate is attached to the workpiece in the grinding process of the workpiece processing method according to the first embodiment. FIG. 13 is a side sectional view showing a grinding process of the processing method of the workpiece according to the first embodiment. FIG. 14 is a flowchart showing the flow of the processing method of the workpiece according to the second embodiment. FIG. 15 is a plan view showing a first positioning step of the processing method for the workpiece according to the second embodiment. FIG. 16 is a side view showing the first cutting step of the work piece processing method according to the second embodiment. FIG. 17 is a side sectional view showing a work piece after the first cutting step of the work piece processing method according to the second embodiment. FIG. 18 is a plan view showing a second positioning step of the work piece processing method according to the second embodiment. FIG. 19 is a side view showing a second cutting step of the work piece processing method according to the second embodiment. FIG. 20 is a side view showing a first planned removal region and a second planned removal region of the work piece processing method according to the second embodiment. FIG. 21 is a side sectional view showing a work piece after the second cutting step of the work piece processing method according to the second embodiment. FIG. 22 is a plan view showing a positioning step of the processing method of the workpiece according to the modified example of each embodiment. FIG. 23 is a diagram showing the magnitude of chipping that occurs when the angle is changed in the processing method according to each embodiment.

A mode for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. In addition, the components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Further, the configurations described below can be combined as appropriate. In addition, various omissions, substitutions or changes of the configuration can be made without departing from the gist of the present invention.

[Embodiment 1]
The processing method of the workpiece according to the first embodiment will be described with reference to the drawings. FIG. 1 is a perspective view showing an example of a work piece to be processed in the work piece processing method according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

In the first embodiment, as shown in FIG. 1, the workpiece W to be processed in the processing method of the workpiece is a disk-shaped semiconductor wafer or an optical device wafer whose base material is silicon, sapphire, gallium, or the like. is there. The workpiece W has a disk shape, and the device D is formed in a region partitioned by a plurality of scheduled division lines L formed in a grid pattern on a flat surface WS. A plurality of devices D are formed on the surface WS of the workpiece W. Further, as shown in FIG. 2, the back surface WR on the back side of the front surface WS of the workpiece W is formed flat. As shown in FIG. 2, the workpiece W is provided with a convexly curved curved surface CF on the outer periphery. For this purpose, the workpiece W includes a flat front surface WS, a back surface WR, and a convexly curved curved surface CF. Further, the workpiece W includes an outer peripheral area ER to be removed, which surrounds the device area DR provided with the plurality of devices D. The planned removal region ER is a region provided on the outer periphery of the workpiece W and on which the device D is not formed, and is at least a curved surface CF, a boundary BS between the front surface WS and the curved surface CF, and a back surface WR and the curved surface CF. Includes the boundary BR with. Further, in the workpiece W according to the first embodiment, a metal or a film is formed in the region ER to be removed.

The processing method of the workpiece according to the first embodiment will be described with reference to the drawings. FIG. 3 is a flowchart showing the flow of the processing method of the workpiece according to the first embodiment. FIG. 4 is a perspective view showing a configuration example of a cutting device used in the method for processing a workpiece according to the first embodiment. FIG. 5 is a plan view showing a first positioning step of the work piece processing method according to the first embodiment. FIG. 6 is a side view showing a first cutting step of the work piece processing method according to the first embodiment. FIG. 7 is a side sectional view showing a work piece after the first cutting step of the work piece processing method according to the first embodiment. FIG. 8 is a plan view showing a second positioning step of the work piece processing method according to the first embodiment. FIG. 9 is a side view showing a second cutting step of the work piece processing method according to the first embodiment. FIG. 10 is a side view showing a first planned removal region and a second planned removal region of the work piece processing method according to the first embodiment. FIG. 11 is a side sectional view showing a work piece after the second cutting step of the work piece processing method according to the first embodiment. FIG. 12 is a side sectional view showing a state in which a substrate is attached to the workpiece in the grinding process of the workpiece processing method according to the first embodiment. FIG. 13 is a side sectional view showing a grinding process of the processing method of the workpiece according to the first embodiment.

The processing method of the work piece according to the first embodiment (hereinafter, simply referred to as a processing method) includes the surface WS of the area ER to be removed on the outer periphery of the work piece W and is thinned from the surface WS. This is a method of removing a portion deeper than the thickness of the object W (indicated by parallel diagonal lines and intersecting parallel diagonal lines in FIG. 10) to perform so-called edge trimming of the workpiece W and thinning the workpiece W. .. As shown in FIG. 3, the processing method includes a first positioning process ST1, a first cutting process ST2, a second positioning process ST3, a second cutting process ST4, and a grinding process ST5. As the processing method, the cutting device 1 which is the processing device shown in FIG. 4 is used in the first positioning process ST1, the first cutting process ST2, the second positioning process ST3, and the second cutting process ST4.

As shown in FIG. 4, the cutting device 1 includes a chuck table 10 that holds the workpiece W, a cutting means 20 that cuts the workpiece W held by the chuck table 10, and a chuck table 10 and cutting. The X-axis moving means 30 that moves the means 20 relative to the X-axis direction parallel to the horizontal direction, and the chuck table 10 and the cutting means 20 move relative to the Y-axis direction parallel to the horizontal direction and orthogonal to the X-axis direction. Control of the Y-axis moving means 40, the Z-axis moving means 50 for moving the chuck table 10 and the cutting means 20 relative to each other in the Z-axis direction orthogonal to both the X-axis direction and the Y-axis direction, and the imaging means 60. It is equipped with means 100.

In the chuck table 10, the work piece W before machining is placed on the holding surface 10a to hold the work piece W. The chuck table 10 has a disk shape in which a portion constituting the holding surface 10a is formed of porous ceramic or the like, is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown), and is placed on the holding surface 10a. The work piece W is held by suction. Further, the chuck table 10 is rotated around the axis parallel to the Z-axis direction by the rotation drive source 11.

The X-axis moving means 30 is a machining feeding means for machining and feeding the chuck table 10 in the X-axis direction by moving the chuck table 10 together with the rotation drive source 11 in the X-axis direction. The Y-axis moving means 40 is an indexing feeding means for indexing and feeding the chuck table 10 by moving the cutting means 20 in the Y-axis direction. The Z-axis moving means 50 is a cutting feeding means that cuts and feeds the cutting means 20 by moving the cutting means 20 in the Z-axis direction. The X-axis moving means 30, the Y-axis moving means 40, and the Z-axis moving means 50 have well-known ball screws 31, 41, 51 and ball screws 31, 41, 51 rotatably provided around the axis around the axis. A well-known pulse motor 32, 42, 52 and a well-known guide rail 33, 43, 53 that movably support the chuck table 10 or the cutting means 20 in the X-axis direction, the Y-axis direction, or the Z-axis direction are provided.

The cutting means 20 accommodates a spindle motor (not shown) that rotates around an axis parallel to the Y-axis direction, and the spindle motor is accommodated in the Y-axis direction and the Z-axis direction by the Y-axis moving means 40 and the Z-axis moving means 50. A spindle housing 21 to be moved and a cutting blade 22 attached to the spindle motor are provided. The cutting blade 22 is a cutting grindstone formed in an ultra-thin ring shape, and is rotated by a spindle motor around an axis parallel to the Y-axis direction to obtain a workpiece W held by the chuck table 10. It is for cutting. In the first embodiment, the thickness of the cutting blade 22 is 1 mm or more and about 3 mm or less.

The imaging means 60 images the workpiece W held on the chuck table 10 and is arranged at a position parallel to the cutting means 20 in the X-axis direction. In the first embodiment, the imaging means 60 is attached to the spindle housing 21. The image pickup means 60 is composed of a CCD camera that captures an image of the workpiece W held on the chuck table 10.

The control means 100 controls each of the above-mentioned components of the cutting device 1 to cause the cutting device 1 to perform a machining operation on the workpiece W. The control means 100 includes an arithmetic processing device having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as a ROM (read only memory) or a RAM (random access memory), and an input / output interface device. It is a computer that has and can execute computer programs. The arithmetic processing unit of the control means 100 executes a computer program stored in the ROM on the RAM to generate a control signal for controlling the cutting device 1. The arithmetic processing unit of the control means 100 outputs the generated control signal to each component of the cutting device 1 via the input / output interface device. Further, the control means 100 is connected to a display means (not shown) composed of a liquid crystal display device for displaying a processing operation state, an image, or the like, or an input means used by an operator when registering processing content information or the like. .. The input means is composed of at least one of a touch panel provided on the display means, a keyboard and the like.

In the first positioning step ST1, the operator places the back surface WR of the workpiece W on the holding surface 10a of the chuck table 10 of the cutting device 1, and instructs the control means 100 to start machining of the cutting device 1 via the input means. It is carried out by inputting. In the first positioning step ST1, a straight line SL (shown by a dotted line in FIG. 5) that bisects the thickness of the cutting blade 22 in the cutting direction of the cutting blade 22 is tangent to the peripheral edge of the workpiece W (FIG. 5). This is the process of positioning in the direction (indicated by the alternate long and short dash line). In the first positioning step ST1, the control means 100 of the cutting device 1 causes the imaging means 60 to image the workpiece W held on the chuck table 10 and aligns the cutting means 20 with the workpiece W. As shown in FIG. 5, the cutting blade 22 is positioned on the peripheral edge of the workpiece W in the plan view of the cutting device 1. In the first positioning step ST1, the control means 100 of the cutting device 1 forms an angle θ between the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG at the peripheral edge of the workpiece W (shown in FIG. 8). ) Is 0 degrees, the chuck table 10 and the cutting blade 22 of the cutting means 20 are positioned. That is, in the first positioning step ST1, the control means 100 positions the tangent TG at the peripheral edge of the workpiece W and the cutting blade 22 in parallel in the plan view of the cutting device 1.

The angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG of the peripheral edge of the workpiece W is the straight line that bisects the thickness of the cutting blade 22 in the plan view of the cutting device 1. It refers to the angle formed by SL and the tangent line TG shown by a bisector in FIG. 5 at a position overlapping the cutting edge of the cutting blade 22 in the peripheral edge portion of the workpiece W.

In the first cutting step ST2, the work piece W is rotated while the cutting blade 22 is cut into the work piece W to remove the first removal of the planned removal region ER of the peripheral portion on the WS side of the surface of the work piece W. This is a step of removing the planned area ER1. In the first cutting step ST2, the control means 100 rotates the cutting blade 22 of the cutting means 20 and causes the Z-axis moving means 50 to move the cutting blade 22 in the Z-axis direction as shown in FIG. By rotating the chuck table 10 around the axis of the rotation drive source 11 while cutting the cutting blade 22 into at least the first planned removal area ER1 of the work piece W to be removed, the work piece W The first planned removal region ER1 on the surface WS side is removed over the entire circumference.

In the first embodiment, as shown in FIG. 10, the first planned removal region ER1 refers to a portion of the planned removal region ER including the boundary BS and on the curved surface CF side of the boundary BS. The first planned removal region ER1 may include a portion closer to the center of the workpiece W than the boundary BS. After the first cutting step ST2, as shown in FIG. 7, the first planned removal region ER1 on the surface WS side of the workpiece W is removed over the entire circumference. In the first embodiment, the first cutting step ST2 is a portion located from the outer periphery of the curved surface CF of the workpiece W to the inner peripheral side from 2 mm to 3 mm and at a depth of about 100 μm to 150 μm from the surface WS (FIG. (Indicated by parallel diagonal lines in 10) is removed.

In the second positioning step ST3, the straight line SL shown by the dotted line in FIG. 8 that bisects the thickness of the cutting blade 22 in the cutting direction of the cutting blade 22 and the alternate long and short dash line in FIG. 8 of the peripheral portion of the workpiece W This is a step of positioning the cutting blade 22 at an angle θ where the tangent line TG indicated by is exceeding 0 degrees. In the first embodiment, the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG at the peripheral edge of the workpiece W is 5 degrees or more.

In the second positioning step ST3, the control means 100 positions the cutting blade 22 on the peripheral edge of the workpiece W in the plan view of the cutting device 1 as shown in FIG. 8 based on the alignment result. In the second positioning step ST3, the control means 100 chucks at a position where the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent TG at the peripheral edge of the workpiece W is 5 degrees or more. The table 10 and the cutting blade 22 of the cutting means 20 are positioned.

In the second cutting step ST4, the workpiece W is rotated while the cutting blade 22 is cut into the workpiece W to remove the second planned removal region ER2 of the planned removal region ER from the workpiece W. It is a process. In the second cutting step ST4, the control means 100 rotates the cutting blade 22 of the cutting means 20 and causes the Z-axis moving means 50 to move the cutting blade 22 in the Z-axis direction as shown in FIG. By rotating the chuck table 10 around the axis of the rotation drive source 11 while cutting the cutting blade 22 into the second planned removal area ER2 of the work piece W, the second planned removal area from the work piece W ER2 is removed over the entire circumference.

In the first embodiment, as shown in FIG. 10, the second planned removal region ER2 includes the boundary BS in the planned removal region ER and includes a portion closer to the center of the workpiece W than the boundary BS. In the present invention, the second planned removal region ER2 may include a region closer to the device region DR of the workpiece W than the first scheduled removal region ER1. After the second cutting step ST4, as shown in FIG. 11, the first planned removal region ER1 and the second scheduled removal region ER2 on the surface WS side of the workpiece W are removed over the entire circumference. There is. In the first embodiment, the second cutting step ST4 is, for example, 1 mm to 1.5 mm from the corner on the surface WS side formed by the first cutting step ST2 of the workpiece W to the inner peripheral side and the surface WS. A portion located at a depth of about 10 μm to 20 μm (indicated by diagonal lines intersecting in FIG. 10) is removed.

The grinding step ST5 is a step of grinding the back surface WR of the workpiece W to thin the workpiece W and remove the planned removal region ER. In the grinding process ST5, as shown in FIG. 12, the substrate SB is attached to the surface WS side of the workpiece W. The substrate SB is formed in a disk shape made of a hard material. The outer diameter of the substrate SB is slightly larger than the outer diameter of the workpiece W.

In the grinding step ST5, as shown in FIG. 13, the substrate SB is suction-held on the holding surface 71a of the chuck table 71 of the grinding apparatus 70, and the grinding wheel 72 is brought into contact with the back surface WR of the workpiece W to chuck. The table 71 and the grinding wheel 72 are rotated around the axis to grind the back surface WR of the workpiece W. As a result, the grinding step ST5 thins the workpiece W and removes the planned removal region ER from the workpiece W over the entire circumference.

The machining method according to the first embodiment is formed by forming a straight line SL that divides the thickness of the cutting blade 22 into two equal parts and a tangent line TG at the peripheral edge of the workpiece W in the plan view of the cutting device 1 in the second positioning step ST3. The chuck table 10 and the cutting blade 22 of the cutting means 20 are positioned at a position where the angle θ exceeds 0 degrees and preferably 5 degrees or more, and the cutting blade 22 is removed in the second cutting step ST4. The planned removal area ER is removed from the workpiece W by cutting into the second planned removal area ER2 including the area closer to the device area DR than the first planned removal area ER1. Therefore, it is possible to suppress chipping that occurs on the outer periphery of the workpiece W after removing the planned removal region ER, and in particular, the straight line SL that bisects the thickness of the cutting blade 22 and the peripheral edge of the workpiece W. When the angle θ formed by the tangent line TG exceeds 0 degrees and is 5 degrees or more, chipping hardly occurs on the outer circumference of the workpiece W. As a result, the processing method according to the first embodiment can remove the planned removal region ER without causing chipping in the workpiece W at the time of edge trimming.

Further, in the processing method according to the first embodiment, the first method is to position the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent TG at the peripheral edge of the workpiece W at a position of 0 degrees. After removing the planned removal region ER1 in the first cutting step ST2, the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent TG at the peripheral edge of the workpiece W exceeds 0 degrees. Since the second planned removal area ER2 including the area closer to the device area DR than the first planned removal area ER1 is removed by positioning the position, the chipping that occurs when the first planned removal area ER1 is removed is second. Can be removed when removing the planned removal area ER2. As a result, the processing method according to the first embodiment can suppress the occurrence of chipping in the vicinity of the device region DR. Therefore, the processing method according to the first embodiment can suppress the occurrence of chipping of the workpiece W at the time of edge trimming, and forms a scratch on the device D after joining the workpiece W in the subsequent steps. It has the effect of being able to suppress the process.

[Embodiment 2]
The processing method of the workpiece according to the second embodiment will be described with reference to the drawings. FIG. 14 is a flowchart showing the flow of the processing method of the workpiece according to the second embodiment. FIG. 15 is a plan view showing a first positioning step of the processing method for the workpiece according to the second embodiment. FIG. 16 is a side view showing the first cutting step of the work piece processing method according to the second embodiment. FIG. 17 is a side sectional view showing a work piece after the first cutting step of the work piece processing method according to the second embodiment. FIG. 18 is a plan view showing a second positioning step of the work piece processing method according to the second embodiment. FIG. 19 is a side view showing a second cutting step of the work piece processing method according to the second embodiment. FIG. 20 is a side view showing a first planned removal region and a second planned removal region of the work piece processing method according to the second embodiment. FIG. 21 is a side sectional view showing a work piece after the second cutting step of the work piece processing method according to the second embodiment. In FIGS. 14 to 21, the same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The processing method of the workpiece according to the second embodiment (hereinafter, simply referred to as a processing method) includes the surface WS of the outer peripheral region ER-2 of the workpiece W to be removed, as in the first embodiment. A portion deeper than the thickness of the work piece W after thinning (indicated by parallel diagonal lines and intersecting parallel diagonal lines in FIG. 20) is removed from the surface WS to perform so-called edge trimming of the work piece W and to be processed. This is a method of thinning the object W. As shown in FIG. 14, the processing methods include a first positioning process ST1-2, a first cutting process ST2-2, a second positioning process ST3-2, and a second cutting process ST4-2. , The grinding step ST5 is included. The processing method is the same as in the first embodiment, in the first positioning step ST1-2, the first cutting step ST2-2, the second positioning step ST3-2, and the second cutting step ST4-2. The cutting device 1 which is the processing device shown in 4 is used.

In the first positioning step ST1-2, the operator places the back surface WR of the workpiece W on the holding surface 10a of the chuck table 10 of the cutting device 1, and processes the cutting device 1 on the control means 100 via the input means. It is carried out by inputting a start instruction. In the first positioning step ST1-2, a straight line SL (shown by a dotted line in FIG. 15) that bisects the thickness of the cutting blade 22 in the cutting direction of the cutting blade 22 and a tangent line TG (tangent line TG) at the peripheral edge of the workpiece W ( It is a step of positioning the cutting blade 22 at an angle θ exceeding 0 degrees (shown by a alternate long and short dash line in FIG. 15). In the second embodiment, the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG at the peripheral edge of the workpiece W is 5 degrees or more.

In the first positioning step ST1-2, the control means 100 of the cutting device 1 causes the imaging means 60 to image the workpiece W held on the chuck table 10, and aligns the cutting means 20 with the workpiece W. This is carried out, and as shown in FIG. 15, the cutting blade 22 is positioned on the peripheral edge of the workpiece W in the plan view of the cutting device 1. In the first positioning step ST1-2, the angle θ formed by the control means 100 of the cutting device 1 between the straight line SL that bisects the thickness of the cutting blade 22 and the tangent TG at the peripheral edge of the workpiece W is 5 degrees. The chuck table 10 and the cutting blade 22 of the cutting means 20 are positioned at the above positions.

In the first cutting step ST2-2, the workpiece W is rotated while the cutting blade 22 is cut from the surface WS of the workpiece W, and the peripheral portion of the surface WS side of the workpiece W is to be removed. This is a step of removing the first planned removal region ER1-2 of -2. In the first cutting step ST2-2, the control means 100 rotates the cutting blade 22 of the cutting means 20 and causes the Z-axis moving means 50 to move the cutting blade 22 in the Z-axis direction as shown in FIG. By rotating the chuck table 10 around the axis of the rotation drive source 11 while cutting the cutting blade 22 into at least the first planned removal area ER1-2 of the work piece W to be removed. , The first planned removal region ER1-2 on the WS side of the surface of the workpiece W is removed over the entire circumference. After the first cutting step ST2-2, as shown in FIG. 17, the first planned removal region ER1-2 on the surface WS side of the workpiece W is removed over the entire circumference.

In the second positioning step ST3-2, the straight line SL shown by the dotted line in FIG. 18 that bisects the thickness of the cutting blade 22 in the cutting direction of the cutting blade 22 is shown in FIG. 18 at the peripheral edge of the workpiece W. This is a step of positioning in the tangent TG direction indicated by the alternate long and short dash line. In the second positioning step ST3-2, the control means 100 places the cutting blade 22 on the peripheral edge of the workpiece W in the plan view of the cutting device 1 as shown in FIG. 18 based on the alignment result. Position. In the second positioning step ST3-2, the angle θ (shown in FIG. 15) formed by the control means 100 between the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG at the peripheral edge of the workpiece W is determined. The chuck table 10 and the cutting blade 22 of the cutting means 20 are positioned at a position of 0 degrees. That is, in the second positioning step ST3-2, the control means 100 positions the tangent TG at the peripheral edge of the workpiece W and the cutting blade 22 in parallel in the plan view of the cutting device 1.

In the second cutting step ST4-2, the workpiece W is rotated while the cutting blade 22 is cut into the workpiece W to cover the second planned removal region ER2-2 of the planned removal region ER-2. This is a step of removing from the work piece W. In the second cutting step ST4-2, the control means 100 rotates the cutting blade 22 of the cutting means 20 and causes the Z-axis moving means 50 to move the cutting blade 22 in the Z-axis direction as shown in FIG. By rotating the chuck table 10 around the axis of the rotation drive source 11 while cutting the cutting blade 22 into the second planned removal area ER2-2 of the workpiece W, the second from the workpiece W The area ER2-2 to be removed is removed over the entire circumference.

In the second embodiment, as shown in FIG. 20, the second planned removal region ER2-2 refers to a portion of the planned removal region ER-2 including the boundary BS and on the curved surface CF side of the boundary BS. In the present invention, the second planned removal region ER2-2 may include a portion closer to the center of the workpiece W than the boundary BS.

Further, in the second embodiment, as shown in FIG. 20, the first planned removal region ER1-2 includes the boundary BS in the planned removal region ER-2 and is closer to the center of the workpiece W than the boundary BS. Although the portion is included, in the present invention, the first planned removal region ER1-2 may include a region closer to the device region DR of the workpiece W than the second scheduled removal region ER2-2. After the second cutting step ST4-2, as shown in FIG. 21, the work piece W has the first planned removal area ER1-2 and the second planned removal area ER2-2 on the surface WS side all around. Has been removed.

The grinding step ST5 is a step of grinding the back surface WR of the workpiece W using the grinding device 70 to thin the workpiece W and remove the planned removal region ER-2, as in the first embodiment. is there.

The machining method according to the second embodiment includes a straight line SL that divides the thickness of the cutting blade 22 into two equal parts and a tangent TG at the peripheral edge of the workpiece W in a plan view of the cutting device 1 in the first positioning step ST1-2. The chuck table 10 and the cutting means 20 are positioned at positions where the angle θ formed by the cutting exceeds 0 degrees and preferably 5 degrees or more, and the cutting blade 22 is to be removed in the first cutting step ST2-2. The first planned removal area ER1-2 including the area closer to the device area DR than the second planned removal area ER2-2 is cut into the work piece W to remove the planned removal area ER-2. For this reason, it is possible to suppress chipping that occurs on the outer periphery of the workpiece W after removing the planned removal region ER-2, and in particular, the straight line SL that bisects the thickness of the cutting blade 22 and the periphery of the workpiece W. When the angle θ formed by the tangent line TG of the portion exceeds 0 degrees and is 5 degrees or more, chipping hardly occurs on the outer circumference of the workpiece W. As a result, the processing method according to the second embodiment can remove the planned removal region ER-2 at the time of edge trimming without causing chipping in the workpiece W.

Further, the processing method according to the second embodiment is positioned at a position where the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent line TG at the peripheral edge of the workpiece W is 0 degrees. Before removing the planned removal area ER2-2 in the second cutting step ST4-2, the angle θ formed by the straight line SL that bisects the thickness of the cutting blade 22 and the tangent TG at the peripheral edge of the workpiece W. Since the first planned removal area ER1-2 including the area closer to the device area DR than the second planned removal area ER2-2 is removed at a position where is over 0 degrees, the second planned removal area ER2- Since the surface WS metal or film is not cut when the 2 is removed, chipping can be suppressed. Further, since the first planned removal region ER1-2 has already been removed before the second cutting step ST4-2 is performed, the volume to be removed in the second cutting step ST4-2 can be reduced. Therefore, it is not necessary to slow down the feed speed of the second cutting step ST4-2, and it is not necessary to use the cutting blade 22 having a large grain size in the second cutting step ST4-2.

[Modification example]
The processing method of the workpiece according to the modified example of each embodiment will be described with reference to the drawings. FIG. 22 is a plan view showing a positioning step of the processing method of the workpiece according to the modified example of each embodiment. In FIG. 22, the same parts as those in each embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the processing method of the workpiece according to the modified example, in the second positioning step ST3 of the first embodiment and the first positioning step ST1-2 of the second embodiment, the angle θ is 90 degrees in the plan view of the cutting device 1. The chuck table 10 and the cutting blade 22 of the cutting means 20 are positioned at such positions. As described above, the method for processing the workpiece of the present invention is the cutting blade in the second positioning step ST3 of the first embodiment and the first positioning step ST1-2 of the second embodiment in the plan view of the cutting device 1. The chuck table 10 and the cutting means 20 are positioned at a position where the angle θ formed by the straight line SL that divides the thickness of 22 into two equal parts and the tangent line TG at the peripheral edge of the workpiece W exceeds 0 degrees, and the angle θ is preferably 5. The chuck table 10 and the cutting means 20 are positioned at positions above and below 90 degrees, and more preferably, the chuck table 10 and cutting means 20 are positioned at positions where the angle θ is 90 degrees.

Next, the inventors of the present invention confirmed the effect of suppressing chipping in the processing method for the workpiece according to the present invention. In the confirmation, the size of chipping generated at the boundary between the cut region and the uncut surface when the planned removal regions ER and ER-2 were removed from the surface WS side of the workpiece W was measured. FIG. 23 is a diagram showing the magnitude of chipping that occurs when the angle is changed in the processing method according to each embodiment. In FIG. 23, the average value of the chipping size is shown by a diamond.

According to FIG. 23, it was clarified that the size of chipping can be suppressed as the angle θ is gradually made larger than 0 degrees. Therefore, according to FIG. 23, it was clarified that chipping can be suppressed at the time of edge trimming by setting the angle θ to an angle exceeding 0 degrees. Further, according to FIG. 23, it was clarified that chipping does not occur when the angle θ is set to an angle of 5 degrees or more. Therefore, according to FIG. 23, it was clarified that chipping can be more reliably suppressed at the time of edge trimming by setting the angle θ to 5 degrees or more. Further, according to FIG. 23, it was clarified that by setting the angle θ to 90 degrees, chipping can be suppressed more reliably at the time of edge trimming.

The present invention is not limited to the above-mentioned first embodiment, second embodiment and modified examples. That is, it can be modified in various ways without departing from the gist of the present invention.

1 Cutting device 10 Chuck table 20 Cutting means 22 Cutting blade 30 X-axis moving means (moving means)
40 Y-axis moving means (moving means)
50 Z-axis moving means (moving means)
100 Control means
ER Scheduled removal area ER-2 Scheduled removal area ER1 1st planned removal area ER1-2 1st planned removal area ER2 2nd planned removal area ER2-2 2nd planned removal area D device DR device area SL straight line ( Cutting direction)
TG tangent line W Work piece WS surface ST1 1st positioning process ST1-2 1st positioning process ST2 1st cutting process ST2-2 1st cutting process ST3 2nd positioning process ST3-2 2nd positioning process ST4 Second cutting process ST4-2 Second cutting process θ angle

Claims (4)

It is a processing method of a work piece that removes a planned removal area on the outer circumference of a disk-shaped work piece having a plurality of devices formed on the surface.
The first positioning step of positioning the cutting direction of the cutting blade in the tangential direction of the peripheral edge of the workpiece, and
The first cutting step of rotating the workpiece while cutting the cutting blade into the workpiece to remove the first planned removal region.
A second positioning step of positioning the cutting blade at an angle where the cutting direction of the cutting blade and the tangent line of the peripheral edge of the workpiece exceed 0 degrees.
A second cutting step of rotating the work piece while cutting the cutting blade into the work piece to remove a second planned removal region, and the like.
A method for processing a workpiece, wherein the second planned removal region includes a region closer to the device region than the first planned removal region. A processing method for a work piece that removes the area to be removed on the outer circumference of the disk-shaped work piece.
The first positioning step of positioning the cutting blade at an angle where the cutting direction of the cutting blade and the tangent line of the peripheral edge of the workpiece exceed 0 degrees.
A first cutting step of rotating the work piece while cutting the cutting blade from the surface of the work piece to remove the first planned removal region.
A second positioning step of positioning the cutting direction of the cutting blade in the tangential direction of the peripheral edge of the workpiece, and
A second cutting step of rotating the workpiece while cutting the cutting blade to remove a second planned removal region, and the like.
A method for processing a workpiece, wherein the first planned removal region includes a region closer to the device region than the second planned removal region. The method for processing a workpiece according to claim 1 or 2, wherein the angle exceeding 0 degrees is 5 degrees or more. The method for processing a workpiece according to claim 1 or 2, wherein the angle exceeding 0 degrees is 90 degrees.

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