Support member and method for treating object to be treated

Abstract

To obtain a support member capable of stably supporting a processing object up to its outer periphery.SOLUTION: A support member (20) is fixed to one surface (11) of a processing object (10) having a chamfered portion (13) on its outer periphery, and the support member has a recess (23) on its fixing surface (21) for fixing to the processing object, which accommodates at least a part of the processing object and conforms to the shape of the chamfered portion.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a support member for supporting an object to be processed, and a processing method for processing an object to be processed. [Background technology]

[0002] When performing any processing on a processing object such as a wafer, the processing object is fixed to a support member and supported by the support member. For example, a dicing tape disclosed in Patent Document 1 is known as a support member. In addition, a support member is used to support the processing object during grinding and polishing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-064885 Summary of the Invention [Problem to be solved by the invention]

[0004] In the case of an object having a chamfered outer periphery, the outer periphery of the object may float above the support member. If the object is processed in this state, the object is unstable at the outer periphery that floats above the support member, which can lead to a problem of poor processing quality.

[0005] An object of the present invention is to provide a support member that can stably support an object to be processed up to its outer periphery, and to provide a method for processing an object to be processed that performs processing while stably supporting the object up to its outer periphery and that achieves excellent processing quality. [Means for solving the problem]

[0006] One aspect of the present invention is a support member that is fixed to one surface of an object to be processed, the object having a chamfered portion on its outer periphery, and the support member is characterized in that the surface that is fixed to the object to be processed has a recess that accommodates at least a portion of the object to be processed and conforms to the shape of the chamfered portion.

[0007] The support member is, for example, a thermoplastic resin having no adhesive layer.

[0008] One aspect of the present invention is a method for processing an object to be processed using the above-mentioned support member, comprising a fixing step of fixing the support member to a first surface of the object to be processed while the object to be processed is positioned in the recess of the support member, and a processing step of processing the object to be processed after the fixing step.

[0009] The processing step includes, for example, a grinding step in which the processing object is thinned with a grinding wheel, and a polishing step in which the processing object is polished with a polishing pad.

[0010] The object to be processed may have a device region in which a device is formed and an excess region surrounding the device region, and the method for processing the object to be processed may include, before the fixing step, a groove forming step of forming a groove at the boundary between the device region and the excess region, the groove having a depth that does not divide the object to be processed.

[0011] The object to be processed may have a device region in which a device is formed and an excess region surrounding the device region, and the method for processing the object to be processed may include, before the fixing step, a modified layer formation step of forming a modified layer that serves as a starting point for separation at the boundary between the device region and the excess region. [Effects of the Invention]

[0012] According to the above-described aspect, by providing the support member with a recess that accommodates at least a portion of the processing object and conforms to the shape of the chamfered portion, it is possible to obtain a support member that can stably support the processing object up to its outer periphery. Also, it is possible to obtain a processing method for processing an object with excellent processing quality, in which the processing is performed while stably supporting the processing object up to its outer periphery. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 4 is a cross-sectional view showing a fixing step of fixing the support member of the first embodiment to the processing object. [Figure 2] FIG. 10 is a cross-sectional view showing an object to be processed and a support member according to a comparative example. [Figure 3] FIG. 10 is a cross-sectional view showing a fixing step of fixing the support member of the second embodiment to the processing object. [Figure 4] 10 is a cross-sectional view showing a state in which a grinding step is performed on a processing object fixed to a support member. FIG. [Figure 5] 10 is a cross-sectional view showing a state in which a polishing step is performed on an object to be processed fixed to a support member. FIG. [Figure 6] FIG. 1 is a perspective view showing a processing object having a device region and a surplus region. [Figure 7] 10 is a cross-sectional view showing a state in which a processing groove forming step is performed on a processing object before it is fixed to a support member. FIG. [Figure 8] 10 is a cross-sectional view showing a state in which a modified layer forming step is performed on a processing object before the processing object is fixed to a support member. FIG. [Figure 9] 10 is a top view of the processing object after the processed groove forming step or the modified layer forming step has been performed. FIG. [Figure 10] 10 is a cross-sectional view showing a fixing step of fixing the processing object having the processed groove formed therein to a support member. FIG. [Figure 11] 10 is a cross-sectional view showing a state in which a grinding step is performed on the processing object after the fixing step. FIG. [Figure 12] 10 is a cross-sectional view showing a state in which a polishing step is performed on the processing object after the fixing step. FIG. [Figure 13] 10 is a cross-sectional view showing a state in which a cutting step is performed on the processing object after the fixing step. FIG. [Figure 14] 5A to 5C are cross-sectional views showing a method for manufacturing a support member. [Figure 15] 10A to 10C are cross-sectional views showing another method for manufacturing a support member. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of a support member and a method for processing an object to which the present invention is applied will be described with reference to the accompanying drawings. The Z-axis direction shown in each drawing is the thickness direction of the plate-shaped object to be processed. When processing the object to be processed, the +Z direction is upward and the -Z direction is downward.

[0015] 1 shows a fixing step of fixing the support member 20 of the first embodiment to the processing object 10. The processing object 10 is, for example, a disk-shaped semiconductor wafer or an optical device wafer, and is made of a material such as silicon, sapphire, or gallium arsenide. The type and material of the processing object 10 are not limited to these examples. The processing object 10 may be a single wafer or a stacked wafer in which multiple wafers are bonded together.

[0016] The processing object 10 has a first surface 11 facing one side in the thickness direction and a second surface 12 facing the other side in the thickness direction. A chamfered portion 13 is formed on the outer periphery of the processing object 10. The chamfered portion 13 has a first curved surface 14 connected to the outer periphery of the first surface 11 and a second curved surface 15 connected to the outer periphery of the second surface 12, and the first curved surface 14 and the second curved surface 15 are connected near the center of the thickness of the processing object 10. The first curved surface 14 and the second curved surface 15 are curved surfaces that incline so that the distance between them in the Z-axis direction decreases as they move toward the outer periphery of the processing object 10. In other words, the thickness of the chamfered portion 13 in the Z-axis direction decreases as they move toward the outer periphery of the processing object 10. The first curved surface 14 and the second curved surface 15 are connected to each other while maintaining their curved shape, and there is no sharp shape between the first curved surface 14 and the second curved surface 15. In this way, the chamfered portion 13 is shaped so as to eliminate any points where the angle changes suddenly on the outer peripheral edge of the object to be processed 10, and by providing the chamfered portion 13, the object to be processed 10 is less likely to crack or chip.

[0017] In the illustrated chamfered portion 13, the first curved surface 14 and the second curved surface 15 are curved surfaces and have an arc-shaped cross-sectional shape, but the chamfered portion may be formed by combining a linear shape and an arc-shaped cross-sectional shape, or may have a polygonal cross-sectional shape. In other words, the chamfered portion only needs to have a shape that makes the outer periphery of the processing object 10 smoother than when the first surface 11 and the second surface 12 are connected by a surface extending in the Z-axis direction.

[0018] The support member 20 has a shape that covers the first surface 11 of the processing object 10, and has a predetermined thickness. The support member 20 has a fixing surface 21 that faces the processing object 10 in the Z-axis direction, and a supported surface 22 that faces the opposite side to the processing object 10. The processing object 10 is fixed to the fixing surface 21 side of the support member 20.

[0019] A recess 23 is formed on the fixing surface 21 of the support member 20. The recess 23 is configured to accommodate a portion of the object 10 to be processed and conforms to the shape of the chamfered portion 13. The recess 23 is recessed toward the supported surface 22, and has a bottom surface 24 and a rising surface 25 located on the outer periphery of the bottom surface 24. The bottom surface 24 is a flat surface facing the first surface 11 of the object 10 to be processed. The rising surface 25 is a surface that protrudes from the bottom surface 24 in the Z-axis direction and conforms to the chamfered portion 13 of the object 10 to be processed. More specifically, the rising surface 25 conforms to the first curved surface 14 of the chamfered portion 13.

[0020] 1, with the first surface 11 of the processing object 10 and the fixing surface 21 (recess 23) of the support member 20 facing each other, the processing object 10 and the support member 20 are moved relatively closer in the Z-axis direction, so that a part of the processing object 10 enters the inside of the recess 23. Then, with the first surface 11 in contact with the bottom surface 24 and the first curved surface 14 of the chamfered portion 13 in contact with the rising surface 25, the support member 20 is fixed to the processing object 10.

[0021] The depth of the recess 23 in the Z-axis direction in the support member 20 is smaller than the thickness of the processing object 10. Therefore, a portion of the processing object 10 in the thickness direction is accommodated in the recess 23, and the other portion is exposed and not accommodated in the recess 23. In the configuration example of FIG. 1 , the depth D of the recess 23 is approximately half the thickness T of the processing object 10, and the lower half of the processing object 10, the outer surface of which is formed by the first surface 11 and the first curved surface 14, is accommodated in the recess 23, and the upper half of the processing object 10, the outer surface of which is formed by the second surface 12 and the second curved surface 15, is exposed and not accommodated in the recess 23.

[0022] Various embodiments can be selected for the material and configuration of the support member 20 and the method for fixing the support member 20 to the processing object 10. In a first embodiment, the support member 20 is made of a tape having an adhesive layer laminated on a base layer, and the adhesive layer is placed on the fixing surface 21 (recess 23) side, so that the support member 20 can be fixed to the processing object 10 by the adhesive force of the adhesive layer.

[0023] In a second embodiment, the support member 20 can be made of a thermoplastic resin tape that does not have an adhesive layer, and the support member 20 can be heated and fixed to the object to be processed 10 by thermocompression bonding.

[0024] In a third embodiment, the support member 20 can be configured as a substrate made of a hard material such as quartz glass, rather than a flexible tape, and the support member 20 can be fixed to the processing object 10 via an adhesive.

[0025] The support member 20 is formed with a recess 23 that accommodates at least a portion of the processing object 10 and conforms to the shape of the chamfered portion 13 of the processing object 10, and is therefore able to stably hold the outer periphery of the processing object 10 having the chamfered portion 13. By performing various processes on the processing object 10 while it is supported by the support member 20, it is possible to prevent quality defects that would occur when the outer periphery of the processing object 10 floats from the support member 20.

[0026] If the depth D of the recess 23 in the Z-axis direction is too shallow, the outer peripheral portion of the object to be processed 10 including the chamfered portion 13 cannot be stably held. Therefore, when processing the object to be processed 10, it is preferable to set the depth D to a value that can stably hold the outer peripheral portion of the object to be processed 10. For example, as shown in FIG. 1, a recess 23 having a depth D about half the thickness of the object to be processed 10 can stably hold the outer peripheral portion of the object to be processed 10.

[0027] On the condition that the outer peripheral portion of the object to be processed 10 can be stably held, it is also possible to apply a recess shallower or deeper than the illustrated recess 23 in the Z-axis direction. Basically, the deeper the recess is and the larger the support area for the chamfered portion 13 is, the higher the effect of stabilizing the position of the object to be processed 10 becomes.

[0028] Also, the appropriate depth of the recess 23 varies depending on the processing and machining conditions for the object to be processed 10. When the relationship between the depth D of the recess 23 and the thickness T of the object to be processed 10 is D≧T, when performing processing on the second surface 12 of the object to be processed 10 such as the grinding and polishing processes described later, not only the object to be processed 10 but also the supporting member 20 on the outer peripheral side thereof will be contacted by the processing tool (grinding wheel or polishing pad). That is, the supporting member 20 will be processed together with the object to be processed 10. Therefore, by setting D<T, the supporting member 20 will not be processed by the processing tool, and it is possible to prevent the deterioration of the processing quality due to processing the supporting member 20 together with the object to be processed 10. In particular, when the object to be processed 10 after processing becomes thinner than before processing by grinding or polishing, by considering the reduction amount R of the thickness of the object to be processed 10 due to processing and making D+R<T, the processing tool can be prevented from contacting the supporting member 20 until the completion of the processing. However, if there are no problems such as deterioration of the processing quality even when the supporting member 20 is processed together with the object to be processed 10, D≧T may be set.

[0029] 1, if the recess has a surface that is in close contact with the second curved surface 15 of the chamfered portion 13 (a surface with an overhanging structure that faces the rising surface 25), this may hinder the operation of bringing the processing object 10 and the support member 20 closer together in the Z-axis direction to allow the processing object 10 to enter the recess when the support member 20 is fixed. Therefore, if the support member 20 is made of a hard material and it is difficult to widen the opening diameter of the recess to allow the processing object 10 to pass through when the processing object 10 is fixed, it is preferable not to provide the support member 20 with an overhanging structure that prevents the processing object 10 from entering the recess, but to make the recess have a flared shape like the recess 23 shown in FIG. 1 (a shape that has only the rising surface 25 whose opening diameter gradually increases with increasing distance from the bottom surface 24).

[0030] 2 shows a support member 100, which is a comparative example of the support member 20 of this embodiment. The support member 100 has a fixing surface 101 that fixes the first surface 11 of the processing object 10, which is an entirely flat surface. Therefore, there is a gap between the first curved surface 14 of the processing object 10 and the fixing surface 101, and the processing object 10 is supported in a state where the chamfered portion 13 is floating above the fixing surface 101 of the support member 100. If various processes are performed on the processing object 10 in this state, there is a risk of quality defects occurring due to the outer periphery of the processing object 10 floating above the support member 100.

[0031] When fixing the processing object 10 to a support member with a uniform thickness, such as the support member 100 of the comparative example, if the support member is flexible, it is possible to apply strong pressure to the region of the processing object 10 inside the chamfered portion 13, thereby deforming the support member so that it is recessed along the processing object 10. However, if the processing object 10 is fixed to the support member in this manner, there is a risk of excessive pressure being applied to the device formation region if a device such as a semiconductor chip is formed on the processing object 10. Therefore, it is preferable to use a configuration in which a recess 23 capable of accommodating at least a portion of the processing object 10 is pre-formed, as in the support member 20 of the present embodiment. By providing the recess 23 in advance, the support member 20 can be fixed without applying excessive load to the processing object 10.

[0032] FIG. 3 shows a fixing step for fixing a support member 26 of the second embodiment to the processing object 10. The recess 23 (bottom surface 24, raised surface 25) of the support member 26 has the same configuration as the support member 20 of the first embodiment, and therefore a description thereof will be omitted. The support member 26 has an outer peripheral portion 27 that surrounds the outside of the central region in which the recess 23 is formed, and a ring-shaped frame 28 is attached to the outer peripheral portion 27. The frame 28 is made of metal or synthetic resin. The frame 28 is fixed to the supported surface 22 on the opposite side from the fixing surface 21 that fixes the processing object 10. The support member 26 with the frame 28 attached is called a support unit 29.

[0033] When the support member 26 is fixed to the first surface 11 of the processing object 10 in the fixing step, a portion of the processing object 10 is accommodated in the recess 23, and the raised surface 25 of the recess 23 supports the processing object 10 along the first curved surface 14 of the chamfered portion 13. This allows the processing object 10 to be stably held without floating up at its outer periphery. Note that the depth of the recess 23 of the support member 26 shown in FIG. 3 is smaller than the depth D of the recess 23 of the support member 20 shown in FIG. 1, and the raised surface 25 of the support member 26 supports the inner region of the first curved surface 14 of the processing object 10 that connects to the first surface 11, but does not support the outer region that connects to the second curved surface 15. The depth of the recess 23 in the support member 26 is set in this manner in consideration of the thinning of the processing object 10 by grinding or polishing, which will be described later. Note that the support member 26 configured as described above can sufficiently stably hold the processing object 10 via the recess 23.

[0034] Next, a description will be given of a processing method for processing the processing object 10. In this processing method, a fixing step shown in Fig. 3 is performed, and the processing object 10 is supported by the support unit 29, and then a processing step for processing the processing object 10 is performed. As specific examples of the processing steps performed on the processing object 10, a grinding step is shown in Fig. 4 and a polishing step is shown in Fig. 5.

[0035] The grinding step will be described with reference to Fig. 4. The grinding step is performed by transporting the workpiece 10 supported by the support unit 29 to the grinding device 30. The grinding device 30 includes a chuck table 31 that holds the workpiece 10 via the support unit 29, and a grinding wheel 32 that is a processing tool arranged above the chuck table 31.

[0036] The chuck table 31 has a holding surface made of a porous material, on which the supported surface 22 of the support member 26 is placed. A suction source 33 sucks air to apply negative pressure to the holding surface of the chuck table 31, thereby suction-holding the support member 26. The chuck table 31 holds the frame 28 with a clamp (not shown). The chuck table 31 is rotated about an axis extending in the Z-axis direction by a table rotation mechanism 34 driven by a motor.

[0037] A plurality of grinding stones 32 are arranged in a ring shape on the underside of the grinding wheel 35. The grinding wheel 35 is attached to a mount provided at the lower end of a spindle 36, which is a rotation shaft extending in the Z-axis direction. The spindle 36 is driven to rotate by a spindle drive mechanism 37 equipped with a motor, and the rotation of the spindle 36 rotates the grinding wheel 35 and the grinding stones 32 on its underside. The spindle 36 is moved in the Z-axis direction by an elevating mechanism 38 composed of a ball screw mechanism, an air cylinder, etc.

[0038] When the workpiece 10 is processed by the grinding device 30, the support member 26 is suction-held on the holding surface of the chuck table 31, and the frame 28 is held by the clamps of the chuck table 31, thereby fixing the workpiece 10 on the chuck table 31 via the support unit 29. The workpiece 10 is held with its second surface 12 facing the grinding wheel 32. The chuck table 31 is rotated by a table rotation mechanism 34, the grinding wheel 35 and the grinding wheel 32 are rotated by a spindle drive mechanism 37, and the spindle 36 is lowered in the -Z direction by an elevation mechanism 38 to bring the grinding wheel 32 closer to the workpiece 10. When the grinding wheel 32 comes into contact with the second surface 12 of the workpiece 10, the workpiece 10 and the grinding wheel 32 are rotated relative to each other, and the grinding wheel 32 is ground. When the workpiece 10 has been ground to a desired thickness, the spindle 36 is raised in the +Z direction by the lifting mechanism 38 to separate the grinding wheel 32 from the workpiece 10, thereby completing the grinding process.

[0039] If grinding is performed to thin the workpiece 10 while the chamfered portion 13 is floating, the outer periphery of the workpiece 10 having the chamfered portion 13 may flap, resulting in chipping. In the grinding step shown in Figure 4, the recess 23 of the support member 26 supports the chamfered portion 13 of the workpiece 10 to prevent it from floating, thereby suppressing flapping of the outer periphery of the workpiece 10 having the chamfered portion 13 and preventing chipping. This improves the processing quality of the workpiece 10 in the grinding device 30.

[0040] 4, the depth of the recess 23 in the support member 26 is smaller than the finished thickness of the workpiece 10 after grinding. Therefore, during grinding, the grinding wheel 32 does not come into contact with the support member 26, and grinds only the workpiece 10. Note that if grinding the support member 26 together with the workpiece 10 with the grinding wheel 32 does not significantly deteriorate the processing quality or processing efficiency, the depth of the recess 23 in the support member 26 may be set to be equal to or greater than the finished thickness of the workpiece 10 after grinding, and the support member 26 may be ground together with the workpiece 10.

[0041] The polishing step will be described with reference to Fig. 5. The grinding step is performed by transporting the workpiece 10 supported by the support unit 29 to the polishing device 40. The polishing device 40 includes a chuck table 41 that holds the workpiece 10 via the support unit 29, and a grinding pad 42, which is a processing tool, arranged above the chuck table 41.

[0042] The chuck table 41 has a holding surface made of a porous material, on which the supported surface 22 of the support member 26 is placed. A suction source 43 sucks air to apply negative pressure to the holding surface of the chuck table 41, thereby suction-holding the support member 26. The chuck table 41 holds the frame 28 with a clamp (not shown). The chuck table 41 is rotated about an axis extending in the Z-axis direction by a table rotation mechanism 44 driven by a motor.

[0043] The grinding stone 32 is attached to the underside of the grinding wheel 45. The grinding wheel 45 is attached to the lower end of a spindle 46, which is a rotation shaft extending in the Z-axis direction. The spindle 46 is driven to rotate by a spindle drive mechanism 47 equipped with a motor, and the rotation of the spindle 46 rotates the grinding wheel 45 and the grinding pad 42 on its underside. The spindle 46 is moved in the Z-axis direction by an elevating mechanism 48 composed of a ball screw mechanism, an air cylinder, etc.

[0044] When the workpiece 10 is processed by the polishing apparatus 40, the support member 26 is suction-held on the holding surface of the chuck table 41, and the frame 28 is held by the clamps of the chuck table 41, thereby fixing the workpiece 10 to the chuck table 41 via the support unit 29. The workpiece 10 is held with its second surface 12 facing the grinding pad 42. The table rotation mechanism 44 rotates the chuck table 41, the spindle drive mechanism 47 rotates the grinding wheel 45 and the grinding pad 42, and the lifting mechanism 48 lowers the spindle 46 in the -Z direction to bring the grinding pad 42 closer to the workpiece 10. When the grinding pad 42 comes into contact with the second surface 12 of the workpiece 10, the workpiece 10 and the grinding pad 42 are rotated relative to each other, and the grinding pad 42 is polished by the grinding pad 42. The polishing process performed by the polishing device 40 may be either chemical mechanical polishing (CMP), which is performed while supplying a polishing liquid to the contact point between the workpiece 10 and the grinding pad 42, or dry polishing, which does not supply a polishing liquid. Once the workpiece 10 has been polished to a desired thickness, the lifting mechanism 48 raises the spindle 46 in the +Z direction to separate the grinding pad 42 from the workpiece 10, completing the polishing process.

[0045] During polishing, the pressure of the grinding pad 42 is more likely to be applied to the outer periphery of the workpiece 10 than to the center. Therefore, if the workpiece 10 is polished while the chamfered portion 13 is unsupported and floating, the outer periphery of the workpiece 10 having the chamfered portion 13 may sag, resulting in an uneven thickness of the polished workpiece 10. In the polishing step shown in FIG. 5 , the chamfered portion 13 of the workpiece 10 is supported by the recess 23 of the support member 26 without any gaps. Therefore, even if the pressure of the grinding pad 42 is concentrated on the outer periphery of the workpiece 10, the outer periphery of the workpiece 10 is held without sagging. This reduces variations in the thickness of the workpiece 10, improving the processing quality of the workpiece 10 in the polishing apparatus 40.

[0046] 5, the depth of the recesses 23 in the support member 26 is smaller than the finished thickness of the workpiece 10 after polishing. Therefore, during polishing, the grinding pad 42 does not come into contact with the support member 26, and polishes only the workpiece 10. Note that if polishing the support member 26 together with the workpiece 10 with the grinding pad 42 does not significantly deteriorate the processing quality or processing efficiency, the depth of the recesses 23 in the support member 26 may be set to be equal to or greater than the finished thickness of the workpiece 10 after polishing, and the support member 26 may be polished together with the workpiece 10.

[0047] 4 and 5, the grinding wheel 32 in the grinding device 30 and the grinding pad 42 in the polishing device 40 are located near the outer periphery 27 of the support member 26 during grinding or polishing. Therefore, if the frame 28 were attached to the fixing surface 21 side of the support member 26, the frame 28 would interfere with the grinding wheel 32 and the grinding pad 42. Therefore, the frame 28 is attached to the supported surface 22 side so that the frame 28 does not interfere with the grinding wheel 32 and the grinding pad 42. Note that if there is no risk of the frame 28 interfering with processing tools such as the grinding wheel 32 and the grinding pad 42, the frame 28 may be attached to the fixing surface 21 side.

[0048] The processing object 16 shown in FIG. 6 has a device region 18 in which devices 17 are formed, and a surplus region 19 surrounding the device region 18. In the processing object 16, the chamfered portion 13 (first curved surface 14, second curved surface 15) has the same configuration as the processing object 10 described above, and therefore description thereof will be omitted. The processing object 16 has, on its first surface 11, a plurality of device formation portions partitioned by lattice-shaped streets S, and devices 17 are formed in each device formation portion. The devices 17 are, for example, semiconductor devices or optical devices. The chamfered portion 13 formed on the outer periphery of the processing object 16 is included in the surplus region 19.

[0049] Next, a processing method for processing the processing object 16 will be described. In this processing method, a processed groove forming step shown in Fig. 7 or a modified layer forming step shown in Fig. 8 is performed to turn the processing object 16 into an intermediate processed state shown in Fig. 9, and then the processing object 16 is fixed to the support unit 29 in a fixing step shown in Fig. 10, and a processing step for processing the processing object 16 is performed. The processing steps performed on the processing object 16 are a grinding step shown in Fig. 11 and a polishing step shown in Fig. 12. In the grinding step and polishing step, grinding and polishing are performed on the second surface 12 opposite to the first surface 11 on which the device 17 is formed.

[0050] The machining groove forming step will be described with reference to Fig. 7. The machining groove forming step is performed by transporting the processing object 16, before it is supported by the support unit 29, to the cutting device 50. The cutting device 50 includes a chuck table 51 that holds the processing object 16, and a cutting blade 52 that is a processing tool arranged above the chuck table 51.

[0051] The chuck table 51 has a holding surface formed of a porous material, and the second surface 12 of the processing object 16 is placed on the holding surface. Air is sucked in by a suction source 53 to apply negative pressure to the holding surface of the chuck table 51, thereby suction-holding the processing object 16. The chuck table 51 is rotated about an axis extending in the Z-axis direction by a table rotation mechanism 54 driven by a motor.

[0052] The cutting blade 52 is attached to the tip of a spindle 55, which is a rotation axis extending horizontally perpendicular to the Z-axis direction. The spindle 55 is driven to rotate by a spindle drive mechanism 56 equipped with a motor, and the cutting blade 52 rotates together with the spindle 55. The spindle drive mechanism 56 is moved in the Z-axis direction by an elevating mechanism 57 composed of a ball screw mechanism, an air cylinder, etc.

[0053] When the cutting device 50 processes the workpiece 16, the workpiece 16 is suction-held on the holding surface of the chuck table 51. The workpiece 16 is held with the first surface 11 facing the cutting blade 52. The cutting blade 52 is positioned above the boundary between the device region 18 and the excess region 19 of the workpiece 16, and then the cutting blade 52 is rotated by the spindle drive mechanism 56. The spindle 55 is lowered in the -Z direction by the lifting mechanism 57 to bring the cutting blade 52 close to the workpiece 16. As the cutting blade 52 rotates, it cuts into the first surface 11 of the workpiece 16. Once the cutting blade 52 has cut into the workpiece 16 to a predetermined depth, the table rotation mechanism 54 rotates the chuck table 51. This forms an annular processing groove 90 extending circumferentially of the workpiece 16 on the first surface 11 side along the boundary between the device region 18 and the excess region 19. Once the processed groove 90 is formed, the spindle drive mechanism 56 is raised in the +Z direction by the lifting mechanism 57 to separate the cutting blade 52 from the processing object 16, thereby completing the cutting process.

[0054] The processed groove 90 is a bottomed half-cut groove formed partway through the thickness of the processing object 16. The processed groove 90 separates the device region 18 from the excess region 19 on the outer periphery when processing steps such as a grinding step ( FIG. 11 ) or a polishing step ( FIG. 12 ) are performed, and acts to prevent the behavior of the excess region 19 side from being transmitted to the device region 18 side. By forming the processed groove 90 on the first surface 11 side of the processing object 16 that is fixed to the support member 26, the above-mentioned effect can be reliably obtained when the second surface 12 side is processed in the grinding step or polishing step to thin the processing object 16.

[0055] The cutting blade 52 has a shape that is thinner in the axial direction on the radially outer periphery side than on the radially central side closer to the spindle 55, so that forming a half-cut groove uses the thinner portion of the cutting blade 52 rather than forming a full-cut groove that penetrates the workpiece 16 in the thickness direction, thereby making it possible to narrow the width of the processed groove 90. As a result, the device region 18 in the workpiece 16 can be widened, and a decrease in the amount (number) of devices 17 formed in the device region 18 can be prevented. In other words, the production efficiency of the devices 17 is improved.

[0056] Instead of cutting using the cutting blade 52 provided on the cutting device 50, the groove 90 may be formed by a method such as laser ablation, which involves irradiating a laser beam, or plasma etching, which involves supplying plasma gas.

[0057] The modified layer forming step will be described with reference to Fig. 8. The modified layer forming step is performed by transporting the processing object 16, before it is supported by the support unit 29, to a laser processing device 60. The laser processing device 60 includes a chuck table 61 that holds the processing object 16, and a laser irradiation unit 62, which is a processing tool, arranged above the chuck table 61.

[0058] The chuck table 61 has a holding surface formed of a porous material, and the second surface 12 of the processing object 16 is placed on the holding surface. Air is sucked in by a suction source 63 to apply negative pressure to the holding surface of the chuck table 61, thereby suction-holding the processing object 16. The chuck table 61 is rotated about an axis extending in the Z-axis direction by a table rotation mechanism 64 driven by a motor.

[0059] The laser irradiation unit 62 focuses a pulsed laser beam oscillated by a laser oscillator using a focusing optical system, and irradiates a processing laser beam L in the -Z direction. The laser irradiation unit 62 can change the focusing point of the laser beam L in the Z axis direction by moving in the Z axis direction or adjusting the focusing optical system.

[0060] When processing the processing object 16 using the laser processing device 60, the processing object 16 is suction-held on the holding surface of the chuck table 61. The processing object 16 is held with the first surface 11 facing the laser irradiation unit 62. The laser irradiation unit 62 is positioned above the boundary between the device region 18 and the excess region 19 of the processing object 16, and then a laser beam L is irradiated from the laser irradiation unit 62. The focal point of the laser beam L is set at a predetermined depth in the thickness direction of the processing object 16, and a modified layer 91 is formed inside the processing object 16. The modified layer 91 is a portion of the processing object 16 whose internal physical properties have been modified by irradiation with the laser beam L to be different from those of the surrounding area. As a result of the modification, the modified layer 91 becomes a region with reduced strength compared to the surrounding area, i.e., a splitting starting point. Furthermore, a crack 92 is formed from the modified layer 91 toward the second surface 12.

[0061] While irradiating the laser beam L from the laser irradiation unit 62, the chuck table 61 is rotated by the table rotation mechanism 64. As a result, a modified layer 91 and a crack 92 are formed in an annular region extending in the circumferential direction of the processing object 16 along the boundary between the device region 18 and the excess region 19. Note that the formation of the crack 92 is not essential, as long as at least the modified layer 91 is formed. Once the formation of the modified layer 91 is complete, the irradiation of the laser beam L from the laser irradiation unit 62 is stopped, and the laser processing is completed.

[0062] 9 shows the processing object 16 in a state where a groove 90 has been formed in the processing groove forming step, or where a modified layer 91 (and cracks 92) has been formed in the modified layer forming step. The annular groove 90 or modified layer 91 is formed along the boundary between the device region 18 and the excess region 19. The chamfered portion 13 in the processing object 16 is included in the excess region 19, and the outer periphery of the processing object 16 having the chamfered portion 13 is partially separated from the device region 18 where the device 17 will be formed by the groove 90 or modified layer 91.

[0063] Next, a fixing step is performed in which the support member 26 is fixed to the processing object 16 in this state. Note that the following steps with reference to Figures 10 to 12 show the case where a processed groove 90 is formed in the processing object 16, but the content of each step is the same even when a modified layer 91 is formed in the processing object 16, and the same action and effect are obtained.

[0064] 10 shows a fixing step in which the support member 26 is fixed to the processing object 16 after the processing groove 90 has been formed. The configuration of the support unit 29 including the support member 26 has already been explained with reference to FIG. 3 and the like, so explanation of the overlapping content will be omitted.

[0065] 10 , the processing object 16 and the support member 26 are oriented such that the first surface 11 and the recess 23 (fixing surface 21) face each other in the Z-axis direction. That is, the processing object 16 is oriented such that the first surface 11, which is the surface opposite to the second surface 12 supported by the chuck table 51 in the previous groove formation step, is supported by the recess 23 of the support member 26. Then, the processing object 16 and the support member 26 are brought relatively close to each other in the Z-axis direction, and the support member 26 is fixed to the processing object 16 with a portion of the processing object 16 inserted inside the recess 23. The groove 90 formed in the processing object 16 faces the recess 23.

[0066] The workpiece 16 with the support member 26 fixed in the fixing step is transported to the grinding device 30, where the grinding step shown in Fig. 11 is performed. The grinding device 30 that performs the grinding step has the same configuration as that previously described with reference to Fig. 4, and the grinding operation performed using the grinding device 30 is also the same as that previously described when grinding the workpiece 10, so a description of the overlapping content will be omitted.

[0067] When the support member 26 after the processing groove 90 is formed is ground by the grinding device 30, the device region 18 and the surplus region 19 are separated by the processing groove 90 on the side of the first surface 11 supported by the support member 26. Therefore, even if the surplus region 19, which is the outer periphery of the processing object 16, becomes wobbly during grinding, the behavior of the surplus region 19 is unlikely to be transmitted to the device region 18, and the processing accuracy of the device region 18 having the devices 17 is unlikely to be affected. Furthermore, the chamfered portion 13 included in the surplus region 19 is supported by the recess 23 of the support member 26 so as not to float, and therefore wobbles are unlikely to occur at the outer periphery of the processing object 16. In this way, by first forming the processing groove 90 and then grinding the workpiece 16, the synergistic effect of the stability of support provided by the support member 26 with the recess 23 makes it possible to extremely effectively prevent chipping on the outer periphery of the workpiece 16, thereby significantly improving the processing quality of the workpiece 10 in the grinding device 30.

[0068] When the modified layer 91 is formed on the processing object 16, the presence of the modified layer 91 between the device region 18 and the excess region 19 makes it difficult for the behavior of the excess region 19 to be transmitted to the device region 18, and therefore it is difficult to affect the processing accuracy of the device region 18 having the devices 17. Therefore, the same effect as when a processed groove 90 is formed on the processing object 16 can be obtained.

[0069] As shown in Figure 11, by thinning the processing object 16 by grinding, the device region 18 and the excess region 19 are completely separated by the processing groove 90, or even if they are not completely separated, most of the area between the device region 18 and the excess region 19 is separated.

[0070] After the grinding step is performed, the workpiece 16 to which the support member 26 is fixed is transported to the polishing device 40, where the polishing step shown in Fig. 12 is performed. The polishing device 40 that performs the polishing step has the same configuration as that described above with reference to Fig. 5, and the polishing operation performed using the polishing device 40 is also the same as that described above when polishing the workpiece 10, so a description of the overlapping content will be omitted.

[0071] As explained above, during polishing, the pressure of the grinding pad 42 tends to be applied more to the periphery of the workpiece 16 than to its center. When polishing a workpiece 16 in which the device region 18 and the excess region 19 are (completely or almost completely) separated by the groove 90, the pressure of the grinding pad 42 applied to the periphery of the workpiece 16 is concentrated on the separated excess region 19, preventing the pressure of the grinding pad 42 from acting strongly locally on the device region 18. Furthermore, the chamfered portion 13 included in the excess region 19 is supported without gaps by the recess 23 of the support member 26, so the periphery of the workpiece 16 is held without sagging. In this way, by first forming the groove 90 and then polishing the workpiece 16, the synergistic effect of the support stability provided by the support member 26 with the recess 23 effectively reduces thickness variations in the workpiece 16, significantly improving the processing quality of the workpiece 10 in the polishing apparatus 40.

[0072] When the modified layer 91 is formed on the processing object 16, the presence of the modified layer 91 between the device region 18 and the excess region 19 makes it easier for the pressure of the grinding pad 42 to be concentrated on the excess region 19, which is less likely to affect the processing accuracy of the device region 18 having the devices 17. Therefore, the same effect as when a processing groove 90 is formed on the processing object 16 can be obtained.

[0073] As a processing step after the fixing step (FIG. 10) of fixing the support member 26 to the processing object 16, a cutting step shown in FIG. 13 may be performed instead of the grinding step or polishing step described above. The cutting device 50 that performs the cutting step has a similar configuration to that described above with reference to FIG. 7, and redundant description will be omitted. Note that it is also possible to choose not to form the processed groove 90 or modified layer 91 in the processing object 16 before the fixing step or cutting step. In this case, unlike the fixing step shown in FIG. 10, the processing object 16 without the processed groove 90 or modified layer 91 is attached to the support member 26.

[0074] 13, the frame 28 is attached to the fixed surface 21 side relative to the outer periphery 27 of the support member 26. When cutting the processing object 16 with the cutting blade 52 of the cutting device 50, the operation is controlled so that the cutting blade 52 does not move to the position of the frame 28, so that the processing can be performed without the frame 28 attached to the fixed surface 21 side interfering with the cutting blade 52.

[0075] The cutting device 50 includes a processing feed mechanism 58 and an indexing feed mechanism 59 that move the chuck table 51 and the cutting blade 52 relative to each other in the horizontal direction. The processing feed mechanism 58 moves the chuck table 51 in a first horizontal direction. The indexing feed mechanism 59 moves the cutting unit, including the cutting blade 52 and the spindle 55, in a second direction perpendicular to the first direction. The second direction is the direction in which the axis of the spindle 55 extends.

[0076] 13, cutting is performed with the cutting blade 52 along grid-like streets S (see FIGS. 6 and 9) formed in the device region 18 of the processing object 16, to form processed grooves 93 along the streets S. The processed grooves 93 may be full-cut grooves that penetrate the processing object 16 in the thickness direction, or may be bottomed half-cut grooves that are formed partway through the thickness of the processing object 16. The cutting device 50 is equipped with a cutting water supply unit that supplies cutting water near the cutting blade 52, and performs cutting on the processing object 16 while supplying cutting water.

[0077] During the cutting step, the workpiece 16 is suction-held on the holding surface of the chuck table 51. The workpiece 16 is held with the first surface 11 facing the cutting blade 52. The cutting blade 52 is positioned above the end of the street S to be cut in the workpiece 16, and then the cutting blade 52 is rotated by the spindle drive mechanism 56. The spindle 55 is lowered in the -Z direction by the lifting mechanism 57 to bring the cutting blade 52 closer to the workpiece 16. As the cutting blade 52 rotates, it cuts into the first surface 11 of the workpiece 16. Once the cutting blade 52 has cut into the workpiece 16 to a predetermined depth, the processing feed mechanism 58 moves the chuck table 51 in a first direction. This forms a cutting groove 93 along the street S extending in the first direction.

[0078] When the formation of the machined groove 93 along one street S is complete, the lifting mechanism 57 raises the spindle drive mechanism 56 in the +Z direction to move the cutting blade 52 away from the workpiece 16. Next, the indexing feed mechanism 59 moves the cutting blade 52 in the second direction to position the cutting blade 52 above the end of the next street S to be cut. Then, in the same manner as above, the cutting blade 52 is lowered in the -Z direction to cut into the workpiece 16, and the machining feed mechanism 58 moves the chuck table 51 in the first direction. This forms the machined groove 93 along the second street S.

[0079] The same operation is repeated to form the machined grooves 93 along all the streets S aligned in the second direction, and then the chuck table 51 is rotated 90 degrees by the table rotation mechanism 54. This causes the uncut streets S to be aligned in the second direction. Then, by repeating the cutting process along the streets S in the same manner as above, the formation of the machined grooves 93 along all the streets S on the processing object 16 is completed.

[0080] Since cutting is performed with a portion of the workpiece 16 housed in the recess 23 of the support member 26, and in particular with the outer periphery of the workpiece 16 supported along the rising surface 25 that follows the chamfered portion 13 and not floating up, chipping can be prevented from occurring in the outer periphery even when a machined groove 93 is formed up to the outer periphery of the workpiece 16 as shown in Figure 13. In other words, since the support member 26 provides stable support over the entire workpiece 16, including its outer periphery, machined grooves 93 can be formed with high precision in all areas of the workpiece 16, and chipping can be suppressed.

[0081] If the outer periphery of the workpiece 16 is raised, chipping is particularly likely to occur when cutting is performed with the cutting blade 52 while cutting water is supplied. For this reason, the support member 26, which supports the outer periphery of the workpiece 16 without raising it, is highly useful in the cutting device 50, which performs cutting while supplying cutting water. However, in addition to the cutting device 50 that performs cutting, the above-mentioned effects of the support member 26 can also be obtained in devices that form grooves in the workpiece 16 by methods such as laser processing, plasma processing, and water jet processing. Furthermore, in addition to devices that form grooves, the support structure for the workpiece 16 using the support member 26 is also useful in devices that deburr by spraying a water jet along the grooves of the street S.

[0082] 13 is performed as a processing step, the cutting blade 52 can cut into the workpiece 16 to form the groove 93 from either the side where the device 17 is formed or the opposite side. In other words, when the processing step is a cutting step, the device 17 may be formed on the second side 12 of the workpiece 16, rather than on the first side 11 fixed to the support member 26. In this respect, the conditions for the placement of the device 17 on the workpiece 16 are slightly different from when the processing step is the grinding step of FIG. 11 or the polishing step of FIG. 12. Therefore, the first side 11 and the second side 12 of the workpiece 16 are defined to distinguish between the side fixed to the support member 26 in the fixing step and the opposite side, and are not a concept that uniquely defines on which side the device 17 is placed.

[0083] As described above, according to the support member and processing method of the object to be processed of each embodiment to which the present invention is applied, the support member provides stable support all the way to the outer periphery of the object to be processed, thereby improving the processing quality in various processes performed on the object to be processed.

[0084] The processing performed on the object to be processed in the processing step may include not only the grinding, polishing, cutting, etc. mentioned above, but also inspection, imaging, transportation, cleaning, film formation, tape application, tape peeling, etc., and may include any processing performed while the object is supported by a support member.

[0085] 14 shows an example of a manufacturing method for manufacturing the above-described support member 20 or support member 26. As shown in the preparation step of FIG. 14(A), support members 20 and 26 are prepared in a state in which there are no recesses 23 and both fixing surface 21 and supported surface 22 are flat, and supported surface 22 is placed on holding table 70.

[0086] A jig 72 having the same shape as the processing objects 10, 16 is held on a movable table 71 that is movable in the thickness direction of the support members 20, 26. The jig 72 has a first surface 73 corresponding to the first surface 11 of the processing objects 10, 16, a first curved surface 74 corresponding to the first curved surface 14, a second surface 75 corresponding to the second surface 12, and a second curved surface 76 corresponding to the second curved surface 15. A chamfered portion 77 is formed by the first curved surface 74 and the second curved surface 76. As shown in FIG. 14 (A) , the movable table 71 holds the second surface 75 of the jig 72, and the first surface 73 of the jig 72 faces the fixing surface 21 of the support members 20, 26.

[0087] After setting up as described above, as in the recess forming step of Fig. 14(B), the moving table 71 is brought close to the holding table 70, and the jig 72 is pressed against the fixing surfaces 21 of the support members 20, 26. When the jig 72 is pressed against the support members 20, 26 with a predetermined force, the fixing surfaces 21 of the support members 20, 26 become recessed, accommodating part of the jig 72.

[0088] As shown in (C) of Figure 14, when the movable table 71 is moved away from the holding table 70 and the jig 72 is retracted from the support members 20, 26, a recess 23 is formed on the fixed surface 21 of the support members 20, 26 as a trace of the jig 72 being pressed against it.

[0089] When forming the recesses 23 of the support members 20, 26, the jig 72 is able to form the bottom surface 24 and the rising surface 25 of the recesses 23 as long as it has at least the first surface 73 and the first curved surface 74. Therefore, the jig 72 may have a shape that does not have the second curved surface 76 around the second surface 75 (the entire side that is held by the moving table 71 may have a flat shape like the second surface 75).

[0090] 15 shows another example of a manufacturing method for manufacturing the above-described support member 20 or support member 26. A tape- or sheet-like material 80, which is the material for support members 20, 26, is prepared. A molding device that shapes material 80 to form support members 20, 26 includes a holding table 81 that holds material 80. Holding table 81 has a holding surface 82 that holds material 80 and has protrusions 83 that correspond to the shapes of objects 10, 16 to be processed.

[0091] 15(A), a material 80 is held on a holding surface 82 of a holding table 81, and a roller 84 presses the material 80 from the side opposite to the holding surface 82. The roller 84 moves in a direction along the holding surface 82, and presses the entire material 80 toward the holding surface 82. The shape of the protrusions 83 of the holding table 81 is transferred to the material 80 by the pressing force applied by the roller 84.

[0092] 15(B), when the formed material 80 is removed from the holding table 81, the support members 20, 26 are completed. The support members 20, 26 have recesses 23 formed thereon as traces of the protrusions 83 of the holding table 81 being pressed against them.

[0093] The manufacturing method of the support members 20, 26 is not limited to that shown in Figures 14 and 15. For example, if the support members 20, 26 are made of a hard material, the recesses 23 can also be formed by cutting.

[0094] The embodiments of the present invention are not limited to the above-described embodiments and modifications, and may be variously changed, substituted, or modified without departing from the spirit of the technical idea of ​​the present invention. Furthermore, if the technical idea of ​​the present invention can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea of ​​the present invention. [Industrial Applicability]

[0095] As described above, the support member of the present invention can provide stable support for a processing object having a chamfered portion all the way to its outer periphery, and is useful in a variety of situations where stable support of the processing object is required. Furthermore, the processing method of the present invention can improve processing quality by processing the processing object while stably supporting the processing object all the way to its outer periphery. [Explanation of symbols]

[0096] 10: Processing object 11: First page (one side) 12:Second side 13: Chamfered part 14: First curved surface 15:Second curved surface 16: Processing object 17: Device 18: Device area 19: Excess area 20: Support member 21:Fixed surface 22: Supported surface 23: Recess 24: Bottom 25: Rising surface 26: Support member 27: Outer periphery 28: Frame 29: Support unit 30: Grinding equipment 31: Chuck table 32: Grinding wheel 35: Grinding wheel 40: Polishing equipment 41: Chuck table 42: Grinding pad 45: Abrasive wheel 50: Cutting equipment 51: Chuck table 52: Cutting blade 60: Laser processing equipment 61: Chuck table 62: Laser irradiation unit 70: Holding table 71: Moving table 72: Jig 80: Material 81: Holding table 83: Convex part 84: Roller 90: Machining groove 91: Modified layer 92: Crack 93: Machining groove L: Laser beam S: Street

Claims

1. A support member fixed to one surface of an object to be processed, the support member having a chamfered portion on its outer periphery, The support member has a recess on its fixing surface for receiving the object, the recess accommodating at least a portion of the object and conforming to the shape of the chamfered portion.

2. 2. The support member of claim 1, wherein the support member is a thermoplastic resin having no glue layer.

3. With the object to be processed positioned in the recess of the support member according to claim 1, a fixing step of fixing the support member to a first surface of the object to be processed; a processing step of processing the object after the fixing step.

4. 4. The method for treating an object according to claim 3, wherein the treating step includes a grinding step of thinning the object with a grinding wheel.

5. 4. The method for treating an object according to claim 3, wherein the treating step includes a polishing step of polishing the object with a polishing pad.

6. the processing object has a device region in which a device is formed and a surplus region surrounding the device region; The method for treating the object to be treated comprises:

6. The method for processing an object according to claim 4 or 5, further comprising, before the fixing step, a groove forming step of forming a groove at the boundary between the device region and the excess region, the groove having a depth that does not divide the object to be processed.

7. the processing object has a device region in which a device is formed and a surplus region surrounding the device region; The method for treating the object to be treated comprises:

6. The method for processing an object according to claim 4, further comprising, before the fixing step, a modified layer forming step of forming a modified layer that serves as a separation starting point at a boundary between the device region and the excess region.

Images