Method of measurement and processing device

Abstract

The present application provides a measuring method and a processing device, which can measure the grinding state of a workpiece surrounded by a grinding wheel. The measuring method comprises: a removing process, in which, for the grinding wheel opposite to the outer edge portion of the workpiece, the grinding wheel is cut into along the thickness direction of the workpiece accommodated in the area surrounded by the grinding wheel in the plan view, so as to remove the outer edge portion of the workpiece; and a first measuring process, in which a first measuring portion is used to measure the state of the outer edge portion of the workpiece ground by the grinding wheel in the removing process.

Description

Technical Field

[0001] This disclosure relates to measurement methods and processing apparatus. Background Technology

[0002] When a workpiece, such as a wafer, is ground thinner to be bonded to a substrate made of silicon, glass, or ceramic, its outer periphery is chamfered. If the workpiece is ground very thin, the outer periphery becomes a so-called cutting edge, which is prone to chipping during the grinding process. This chipping can then extend to devices on the wafer, causing device breakage. As a countermeasure to the cutting edge, edge trimming (removing the outer periphery of the workpiece) is known.

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2015-217461 Summary of the Invention The technical problem that the invention aims to solve The purpose of this disclosure is to provide a method and processing apparatus for measuring the grinding state of a workpiece near the grinding location.

[0004] Technical solutions for solving the problem The measurement method of the first technical solution disclosed herein includes: a removal step in which a grinding wheel connected to a rotatable flange and opposite to the outer edge of a workpiece is driven into the workpiece along the thickness direction of the workpiece housed in an area surrounded by the grinding wheel in a top view, thereby grinding away the outer edge of the workpiece; and a first measurement step in which a first measurement unit measures the state of the outer edge of the workpiece ground by the grinding wheel in the removal step.

[0005] The processing apparatus of the second technical solution of this disclosure includes a grinding wheel and a first measuring unit. The grinding wheel is connected to a rotatable flange and is opposite to the outer edge of the workpiece. The first measuring unit measures the state of the workpiece. The processing apparatus causes the grinding wheel to cut in along the thickness direction of the workpiece, which is housed in the area surrounded by the grinding wheel in a top view, thereby grinding the outer edge of the workpiece. The first measuring unit measures the state of the outer edge of the workpiece ground by the grinding wheel.

[0006] Invention Effects Using this disclosure, it is possible to determine the grinding condition of a workpiece surrounded by a grinding wheel. Attached Figure Description

[0007] Figure 1 This is a side view of the processing apparatus 1 according to an embodiment of the present disclosure.

[0008] Figure 2 This is a top view of flange 24 as viewed from the Z-axis direction.

[0009] Figure 3 This is a top view of the grinding wheel 21b as viewed from the Z-axis direction.

[0010] Figure 4 This is a diagram illustrating an example of the hardware structure of control device 8.

[0011] Figure 5 This is a flowchart illustrating the operation of processing device 1.

[0012] Figure 6 This is a diagram used to illustrate the operation of processing device 1.

[0013] Figure 7 This is a diagram used to illustrate the operation of processing device 1.

[0014] Figure 8 This is a diagram used to illustrate the operation of processing device 1.

[0015] Figure 9 This is a diagram showing a structural example of the processing apparatus 1A in the first modified example.

[0016] Figure 10 This is a top view of flange 24A as viewed from the Z-axis direction.

[0017] Figure 11 This is a top view of the grinding wheel 21C as viewed from the Z-axis direction.

[0018] Figure 12 It is a diagram used to illustrate the processing state of the workpiece W processed by the processing device 1A.

[0019] Figure 13 It is a diagram used to illustrate the processing state of the workpiece W processed by the processing device 1A.

[0020] Figure 14 It is a diagram used to illustrate the processing state of the workpiece W processed by the processing device 1A.

[0021] Figure 15 This is a diagram used to illustrate another processing state of the workpiece W processed by the processing device 1A.

[0022] Figure 16 This is a diagram showing the structure of the processing device 1B in the second modified example.

[0023] Figure 17 This is a flowchart illustrating the operation of the processing device 1B.

[0024] Figure 18 This is a diagram showing the structure of the processing apparatus 1C in the third modified example.

[0025] Figure 19This is a flowchart illustrating the operation of the processing device 1C.

[0026] Figure 20 This is a diagram showing the structure of the processing device 1D in the fourth modified example.

[0027] Figure 21 It is a diagram used to illustrate the processing state of the workpiece W processed by the processing device 1D.

[0028] Figure 22 This is a diagram showing a structural example of one of the other grinding wheels 21.

[0029] Figure 23 This is a diagram showing two other structural examples of the grinding wheel 21. Detailed Implementation

[0030] The embodiments will now be described with reference to the accompanying drawings. Furthermore, in each drawing, identical or equivalent components are labeled with the same or similar reference numerals, and sometimes repeated descriptions are omitted. In each drawing, the X-axis, Y-axis, and Z-axis are intersecting directions, for example, perpendicular directions; the X-axis and Y-axis are horizontal directions; and the Z-axis is a vertical direction. Therefore, the end of the arrow in the Z-axis direction is sometimes referred to as "up," and the opposite side is sometimes referred to as "down." Additionally, a view taken from above along the Z-axis is sometimes referred to as a top view.

[0031] Figure 1 This is a side view of the processing apparatus 1 according to an embodiment of the present disclosure. The processing apparatus 1 is an apparatus for grinding away the outer edge W_O of a workpiece W. As a countermeasure against the cutting edge of a workpiece W such as a bonded wafer formed by bonding multiple wafers, the processing apparatus 1 can perform edge trimming. The workpiece W is typically a silicon workpiece used for the manufacture of semiconductor devices, also called a silicon wafer. As for the structure of the workpiece W, for example, there is a structure obtained by bonding a protective workpiece or BG tape to a wafer on which a device is formed, or a mirror wafer without a device formed, etc., which is patterned with circuits, etc.

[0032] The processing device 1 may include a grinding section 2, a holding device 3, a column 4, a control device 8, and a measuring section 9. The grinding section 2 grinds the workpiece W, and the holding device 3 is a device that holds the workpiece W so that it can rotate.

[0033] (Grinding section 2) The grinding unit 2 may include at least a grinding wheel (or sometimes simply a grinding wheel) 21 capable of grinding the workpiece W, a spindle 22, a feed mechanism 23, and a flange (or sometimes a support) 24. The flange 24 is mounted at the end of the spindle 22, and the grinding wheel 21 is mounted on the flange 24. The spindle 22, for example, is rotated by a motor (not shown) or the like, around a rotation axis a1 in a rotational direction. Here, the rotational direction is, in plan view, a direction that intersects, for example, the radial direction orthogonal to the radial direction, and is the same as the circumferential direction.

[0034] The feed mechanism 23 may include: two linear guides 23a connecting the column 4 to the spindle 22; and a ball screw sliding mechanism (not shown) that causes the spindle 22 to move up and down in the vertical direction.

[0035] The flange 24 is mounted coaxially with the spindle 22. Alternatively, the flange 24 may not be coaxial with the spindle 22. The flange 24 may have at least one hole 24H1 extending through the flange 24 along the Z-axis direction. Figure 2 In the example shown, a plurality of holes 24H1 are formed on the outer edge (outer periphery) of the flange 24. Alternatively, a plurality of holes 24H1 may be formed on the flange 24 at a position further inward than the outer edge. The plurality of holes 24H1 can be formed from the first surface 24_1 on the workpiece W side of the flange 24 (see reference). Figure 1 The second surface 24_2, which faces the flange 24 on the side opposite to the first surface 24_1 (see reference). Figure 1 The holes 24H1 can be arranged separately from each other in the direction of rotation about the axis of rotation a1. Alternatively, the holes 24H1 can be arranged continuously in the direction of rotation. The hole 24H1 can also be a single hole formed in the direction of rotation. In addition, if the diameter of the flange 24 is smaller than the diameter of the grinding wheel 21, the hole 24H1 may not be provided.

[0036] The grinding wheel 21 has a grinding wheel base (grinding wheel platform) 21a and at least one grinding wheel 21b. Hereinafter, one grinding wheel 21b is sometimes referred to as grinding wheel 21b, and multiple grinding wheels 21b are sometimes referred to as grinding wheels 21b. The grinding wheel 21 is mounted on the flange 24 on the side opposite to the spindle 22.

[0037] The grinding wheel holder 21a is mounted coaxially with the flange 24. Alternatively, the grinding wheel holder 21a may not be coaxial with the flange 24. The diameter of the grinding wheel holder 21a is, for example, equal to the diameter of the flange 24. Alternatively, the diameter of the grinding wheel holder 21a may be larger or smaller than the diameter of the flange 24. The grinding wheel holder 21a may be, for example, a hollow annular member, but it may also be formed in other shapes.

[0038] The grinding wheel 21b is mounted on the outer edge (outer periphery) of the grinding wheel holder 21a on the side opposite to the flange 24. The grinding wheel 21b is mounted coaxially with the grinding wheel holder 21a. That is, the grinding wheel 21b is arranged coaxially with the spindle 22. Alternatively, the grinding wheel 21b may not be coaxial with the grinding wheel holder 21a. Figure 3 In the example shown, multiple grinding wheels 21b are arranged in a ring at predetermined intervals along the direction of rotation. Viewed from above, the multiple grinding wheels 21b are configured to surround the workpiece W. That is, the diameter of the grinding wheels 21b is relatively large compared to the diameter of the workpiece W. Furthermore, the diameter of the grinding wheels 21b can be the same as or smaller than the diameter of the workpiece W.

[0039] The grinding wheel 21b is configured such that a portion of it abuts against the outer edge W_O of the workpiece W when the spindle 22 is lowered by the feed mechanism 23 and it is fed downwards in the Z-axis direction. For example, the grinding wheel 21b is configured such that its inner cutting edge abuts against the outer edge W_O of the workpiece W when the spindle 22 is lowered by the feed mechanism 23 and it is fed downwards in the Z-axis direction. Alternatively, the grinding wheel 21b can be configured such that its entire lower surface abuts against the outer edge W_O of the workpiece W when it is fed downwards in the Z-axis direction, or its outer cutting edge abuts against the outer edge W_O of the workpiece W. Here, the portion of the grinding wheel 21b that is radially inward of the outer cutting edge is sometimes referred to as the inner cutting edge, and the portion of the grinding wheel 21b that is radially outward of the inner cutting edge is sometimes referred to as the outer cutting edge. For example, the portion radially inward of the grinding wheel 21b that is about halfway inward is sometimes referred to as the inner cutting edge, but sometimes the portion from about halfway outward to the inner end is also referred to as the inner cutting edge.

[0040] The grinding wheel 21 may have at least one hole 21H extending through along the Z-axis. Figure 3 In the example shown, the grinding wheel 21 has a plurality of holes 21H extending through the grinding wheel holder 21a along the Z-axis. The plurality of holes 21H can be arranged at intervals along the rotation direction. The holes 21H can be formed between two adjacent grinding wheels 21b that are at intervals along the rotation direction. The plurality of holes 21H can be respectively connected to… Figure 2 The multiple holes 24H1 shown are connected in the Z-axis direction. Furthermore, the number of holes 21H is not limited to multiple; one or more is sufficient. For improving measurement accuracy, it is preferable to have two or more holes 21H on the grinding wheel 21. Alternatively, the grinding wheel 21 can also be as follows... Figure 22 As shown, at least one hole 21H is formed, penetrating the grinding wheel holder 21a and the grinding wheel 21b along the Z-axis direction. Furthermore, the grinding wheel 21 may also be as shown... Figure 23 As shown, at least one hole 21H is formed through the grinding wheel holder 21a along the Z-axis direction; and at least one hole 21H is formed through the grinding wheel holder 21a and the grinding wheel 21b along the Z-axis direction.

[0041] (Workpiece W) Workpiece W comprises a wafer. Workpiece W can be formed from materials such as single-crystal silicon. Workpiece W can also be formed from materials other than silicon, such as sapphire, GaAs (gallium arsenide), InP (indium phosphide), GaN (gallium nitride), SiC (silicon carbide), quartz glass, borosilicate glass, lithium tantalate, ceramics, etc. Workpiece W can also be formed from other materials. Workpiece W is, for example, a laminated wafer formed by bonding multiple wafers together. Alternatively, workpiece W can also be a single ordinary wafer. Workpiece W has an outer edge W_O on its radially outer side. The outer edge W_O is a region removed by edge trimming from the end of the outer edge (outer periphery) of workpiece W to a position radially inward separated from that end by a predetermined distance; for example, it is an annular region.

[0042] (Holding device 3) The retaining device 3 is located below the grinding section 2. The retaining device 3 may include a chuck 31 and an air bearing 32.

[0043] An adsorption body can be embedded on the upper surface of the chuck 31. The holding device 3 can be contained within an unshown conduit that passes through the chuck 31 and the air bearing 32 and extends towards the surface of the chuck 31. This conduit can be connected to a vacuum source, a compressed air source, and a water supply source (also unshown) via a rotary joint (unshown) connected to the rotor 32a of the air bearing 32. When the vacuum source is activated, the workpiece W placed on the chuck 31 is adsorbed and held in the chuck 31. When adsorbed and held in the chuck 31, the workpiece W can be housed within the area surrounded by the grinding wheel 21b in plan view. Alternatively, the workpiece W can be configured such that, when adsorbed and held in the chuck 31, a portion of the workpiece W is housed within the area surrounded by the grinding wheel 21b in plan view. Furthermore, when the compressed air source or water supply source is activated, the adsorption of the workpiece W on the chuck 31 is released.

[0044] The air bearing 32 may include a rotor 32a rotatable about a rotation axis a2 and a stator 32b disposed on the outer periphery of the rotor 32a. The rotor 32a and the chuck 31 may be fixed by fastening components such as bolts (not shown). The rotor 32a is connected to a rotary joint, causing the chuck 31 to rotate about the rotation axis a2 in the rotational direction. Here, the rotational direction of the chuck 31 may be either the same as or opposite to the rotational direction of the grinding wheel 21b. A predetermined gap (air gap) is provided between the rotor 32a and the stator 32b, and by supplying compressed air from the outside into this gap, the rotor 32a can rotate relative to the stator 32b in a non-contact manner.

[0045] (Measurement Section 9) The measuring unit 9 can be interpreted as a sensor capable of detecting the thickness of the workpiece W in a non-contact manner. The measuring unit 9 can be interpreted as the first measuring unit of this disclosure. The measuring unit 9 is, for example, an optical sensor, in which a self-emitting part emits visible light and infrared light, and a light-receiving part detects changes in the light reflected by the detected object to obtain an output signal. The measuring unit 9 can also be a laser sensor instead of an optical sensor; in this case, a laser is used instead of visible light or infrared light. The characteristic of optical or laser sensors is that, although they may be affected by water, they can increase the distance from the detected object, so even in environments with splashing water, they can detect the state of the workpiece W from a position a certain distance away from it. Furthermore, the measuring unit 9 is not limited to a non-contact sensor; it can be any sensor capable of detecting the thickness of the workpiece W through the through-holes (hole 21H, hole 24H1, etc.) described later, and can be, for example, a contact sensor or other types of sensors.

[0046] The measuring part 9 can be disposed on the upper part of the flange 24, for example, fixed to the housing 2a of the grinding unit 2. Specifically, the measuring part 9 can be fixed to the housing 2a of the grinding unit 2 at a position where its lower end faces the surface of the workpiece W via a hole 24H1 formed in the flange 24 and a hole 21H formed in the grinding wheel 21b. The center position of the measuring part 9 can be disposed directly above the radial center of the grinding wheel 21b. Alternatively, the center position of the measuring part 9 can be disposed directly above the radial center of the inner cutting edge of the grinding wheel 21b, i.e., the outer edge W_O. Furthermore, the method of fixing the measuring part 9 is not limited to this; for example, it can be fixed to a support member extending vertically from the ground on which the processing device 1 is provided. In other words, it is sufficient to support the measuring part 9 at a position where its lower end faces the surface of the workpiece W via a hole 24H1 formed in the flange 24 and a hole 21H formed in the grinding wheel 21b, replacing the housing 2a. The measuring unit 9 can also be configured within a passage formed inside the flange 24, grinding wheel seat 21a, or spindle 22, etc., to measure the state of the outer edge W_O by means of a mirror or the like. Alternatively, the measuring unit 9 can be configured in a location other than those described above, as long as it can measure the state of the outer edge W_O.

[0047] The measuring unit 9 can be connected to the control device 8 via a control signal line, receive commands from the control device 8 to control its operation, and send data related to the detected workpiece W to the control device 8. This data may include the thickness of the workpiece W at a position relative to its center (in other words, the relationship between the position relative to the center of the workpiece W and its thickness), the surface roughness of the workpiece W, etc. This data can be temporarily stored in memory or stored in a storage device for a longer period.

[0048] The measuring unit 9 can measure the state of the outer edge portion W_O of the workpiece W, for example, through a hole 24H1 through which the flange 24 passes. Specifically, the measuring unit 9 can measure the state of the outer edge portion W_O of the workpiece W through the hole 24H1 through which the flange 24 passes and the hole 21H through which the grinding wheel 21 passes. That is, the measuring unit 9 can measure the state of the outer edge portion W_O of the workpiece W through a through hole extending from the upper surface (first surface) 24S of the flange 24 to the lower surface (second surface) 21S of the grinding wheel 21 (e.g., grinding wheel holder 21a). Alternatively, the measuring unit 9 can be configured to measure the state of the outer edge portion W_O without passing through the holes in the flange 24 and / or the grinding wheel 21.

[0049] In machining apparatuses where the workpiece is surrounded by a grinding wheel, structural limitations restrict the placement of sensors and other detectors, making it difficult to accurately monitor the workpiece's condition during grinding. While it's possible to install a measuring instrument in the feed mechanism to estimate the grinding amount by measuring the feed rate, the grinding wheel wears as the workpiece progresses, making it difficult to accurately measure the amount of material removed from the workpiece W. In the machining apparatus 1 of this disclosure, the measuring unit 9 can directly measure the condition of the workpiece, specifically the outer edge W_O of the workpiece W, through a through-hole that passes through the flange 24 and the grinding wheel 21. Therefore, even when the workpiece W is surrounded by the grinding wheel 21b, the condition (thickness, roughness) of the workpiece W during grinding by the grinding wheel 21b can be easily observed near the workpiece being machined (ground). This improves the productivity and quality of the grinding process. Furthermore, since the machined portion of the workpiece W is constantly monitored, the cause of any errors occurring during machining can be addressed immediately. In addition, the grinding state of the workpiece W can be observed with high precision by effectively utilizing the space formed between two adjacent grinding wheels 21b.

[0050] (Control device 8) The control device 8 can control each component constituting the processing device 1 individually. The control device 8 can, for example, be a computer. Figure 4 As shown, it may include a processor 81, memory 82, storage 83, communication interface 84, and power supply 85.

[0051] The processor 81 may be, for example, a central processing unit (CPU). The processor 81 can be interpreted as the control unit of this disclosure.

[0052] The processor 81 can send control signals to various components of the processing apparatus 1 based on control instructions stored in the memory 82, thereby controlling each component. The processor 81 can process various information in the control device 8. The processor 81 can be a single processor or two or more processors. The processor 81 may include a CPU, a graphics processing unit (GPU), a microprocessor, a circuit board, and other circuits. The processor 81 can execute programs and manipulate data to perform actions of the control device 8, including actions using any of the algorithms, methods, functions, processes, procedures, and sequences described in this disclosure.

[0053] Memory 82 can temporarily or permanently store programs, data, etc., used for information processing in control device 8. Memory 82 can store programs used by control device 8 to make various decisions and judgments. These programs can be added to or modified afterward (i.e., after control device 50 is manufactured). Memory 82 can be a single memory or two or more memory units. Memory 82 can include volatile memory such as RAM (Random Access Memory) and cache, as well as non-volatile memory such as ROM (Read Only Memory). Memory 82 can store programs containing control instructions, etc., which, when executed by processor 81, can control processing device 1.

[0054] The memory 83 can also store measurement values ​​of the state of the ground workpiece W as needed. The memory 83 can store programs used by the control device 8 to make various judgments and decisions. The memory 83 can store other programs, including an operating system, that can be executed by the control device 8 or other devices. The memory 83 can include hard disk drives (HDDs), solid-state drives (SSDs), and flash memory, etc.

[0055] The communication interface 84 can send control signals to control the operation of the holding device 3, grinding unit 2, feed mechanism 23, and measuring unit 9. The components of the control device 8 (processor 81, memory 82, storage 83, and communication interface 84) can be connected to and communicate with each other via buses such as system bus and control bus.

[0056] Power supply 85 typically includes a power plug for connecting to power from a commercial power source or other power source. Power supply 85 may also include a replaceable or non-replaceable battery, which may also be able to accept and charge power from a commercial power source or other power source.

[0057] In the hardware structure of the control device 8, programs and / or data stored in memory 82 and / or storage 83 may be stored in a non-transitory computer-readable medium. The non-transitory computer-readable medium stores computer-readable commands and / or data used to execute methods implemented by the computer. The computer-readable medium may include magneto-optical discs and optical memory devices, digital video discs (DVDs), CD-ROMs (disc read-only memories), DVD+ / -Rs (recordable digital video discs), DVD-RAMs (rewritable digital video discs), DVD-ROMs (read-only digital video discs), HD-DVDs (high-definition digital video discs), and Blu-ray discs (registered trademarks), etc. The computer-readable medium may also include magnetic devices such as magnetic tapes, cassette tapes, cartridge memory, and removable disks. Each program, for execution by an information processing device including a computer (in this embodiment, the control device 8), or for controlling the operation of the information processing device, may include one or more modules of computer program commands encoded in a tangible non-transitory computer-readable medium. Alternatively, the program and / or data can also be configured to be downloaded from an external device via a network.

[0058] (Removal section 81a) The removal section 81a can further press the grinding wheel 21b downward while rotating it, and cut into the workpiece W in the downward direction (thickness direction) of the workpiece W, thereby performing the work of grinding and removing the outer edge W_O of the workpiece W (edge ​​trimming). The grinding wheel 21b is conveyed downward as the spindle 22 is lowered by the feed mechanism 23, and comes into contact with the surface of the outer edge W_O of the workpiece W.

[0059] (Condition Measurement Unit 81b) The state measuring unit 81b uses the measuring unit 9 to measure the state of the outer edge W_O of the workpiece W. The state measuring unit 81b uses the measuring unit 9 (first measuring unit), which is an optical sensor, to measure the state of the outer edge W_O of the workpiece W through the hole 24H1 through which the flange 24 and the grinding wheel 21 pass. The state measuring unit 81b uses the measuring unit 9 to measure the state of the outer edge W_O of the workpiece W being ground by the grinding wheel 21b through the hole 24H1.

[0060] (Adjustment section 81c) The adjustment unit 81c may perform at least one of shaping dressing of the grinding wheel 21b and sharpening dressing of the grinding wheel 21b based on the measurement results obtained by the condition measurement unit 81b.

[0061] Next, refer to Figures 5-8The operation of the machining apparatus 1 is explained. Using the machining apparatus 1 described above, the machining of the workpiece W described below is performed. The machining of the workpiece W can be provided in the form of a program for causing the processor 81 of the control device 8 to perform the prescribed actions or in the form of a non-transitory computer-readable medium storing the program, and the control device 8 controls the various components of the machining apparatus 1.

[0062] Figure 5 This is a flowchart illustrating the operation of the machining apparatus 1. The workpiece W to be ground is placed in the chuck 31 (S1). Typically, at this time, a robotic arm (not shown), controlled by the control device 8, removes one workpiece W from a plurality of workpieces W housed in a box (not shown) and places it in the chuck 31. The workpiece W is placed in the chuck 31 with the grinding surface facing upwards and the center of the workpiece W aligned with the rotation center of the chuck 31.

[0063] The processing device 1 adsorbs and holds the workpiece W placed on the chuck 31 (S2). After the workpiece W is adsorbed and held, the grinding wheel 21b cuts into the workpiece W in the thickness direction of the area contained in the area surrounded by the grinding wheel 21b in the view from above, thereby grinding away the outer edge W_O of the workpiece W (S3).

[0064] For example, as part of the removal process S3, according to instructions from the control device 8, the chuck 31 rotates, the spindle 22 rotates, and the feed mechanism 23 descends. The grinding wheel 21b, rotating and descending appropriately, contacts the outer edge W_O of the rotating workpiece W, thereby machining the workpiece W (see reference). Figures 6-8 Additionally, in Figure 8 In the text, the workpiece W and the spindle 22 (flange 24) are described as rotating in opposite directions, but they can also rotate in the same direction.

[0065] The processing apparatus 1 uses a measuring unit (first measuring unit) 9 to measure the state of the outer edge W_O of the workpiece W being ground by the grinding wheel 21b in the removal process (S4). While measuring the processing state of the workpiece W, such as the processing state of the outer edge W_O of the workpiece W, the processing amount and processing position of the workpiece W are adjusted (S5).

[0066] The processing unit 1 determines whether the grinding of workpiece W has been completed (S6). Typically, the control unit 8 determines whether grinding of workpiece W has been completed by determining whether a preset thickness amount of grinding has been performed. If the grinding of workpiece W has not been completed, the processing unit 1 repeats the process after S3.

[0067] After grinding of workpiece W is completed, the machining device 1, according to the instruction from the control device 8, raises the feed mechanism 23, stops the rotation of the spindle 22, and stops the rotation of the chuck 31 (S7). The machining device 1 releases the gripping and holding of workpiece W on the chuck 31 (S8) and removes the ground workpiece W from the chuck 31 (S9). Regarding the removal of workpiece W, typically, a robotic arm (not shown) controlled by the control device 8 grasps the workpiece W placed on the chuck 31 and houses it in a box (not shown) for the machined workpiece W, thereby removing the workpiece W.

[0068] The machining apparatus 1 described above can sense the state of the workpiece W near the machining position where it is being processed by the grinding wheel 21b. Therefore, even if the workpiece W is surrounded by the grinding wheel 21b, the state (thickness, roughness) of the workpiece W during the grinding process can be easily observed. Consequently, the productivity and machining quality of the grinding process of the workpiece W can be improved. Furthermore, since the machined portion of the workpiece W can be monitored continuously, the cause of the error can be addressed immediately even if an error occurs during machining.

[0069] Hereinafter, a variation of the processing apparatus 1 according to the embodiments of the present disclosure will be described.

[0070] (Example 1) Figure 9 This is a diagram showing a structural example of the processing apparatus 1A in the first modified example. The processing apparatus 1A can be replaced by a measuring unit 9A, a grinding wheel 21C, and a flange 24A. Figure 1 The measuring section 9, grinding wheel 21, and flange 24 are shown. In the first modification, the measuring section 9A can be interpreted as the first measuring section of this disclosure. The measuring section 9A can be located at a position closer to the measuring section 9, for example, closer to the spindle 22.

[0071] At least one hole 24H2 extending through the flange 24A along the Z-axis direction can be formed in the flange 24A. For example... Figure 10 as well as Figure 11 As shown, a plurality of holes 24H2 extending through the flange 24A along the Z-axis direction can be formed in the flange 24A. The plurality of holes 24H2 can be arranged separately from each other along the rotation direction. The plurality of holes 24H2 can be formed in a region of the flange 24A that is closer to the inner side of the grinding wheel 21C. Specifically, the plurality of holes 24H2 can be formed in the region between the spindle 22 and the grinding wheel 21b, the spindle 22 being the rotating shaft that supports the flange 24A for rotation. Where the grinding wheel 21C is not formed... Figure 3The hole 21H is shown. When configured in this way, the grinding state of the workpiece W, housed within the area surrounded by the grinding wheel 21b, can be observed through the hole 24H2 through which the flange 24A passes. Furthermore, the number of holes 24H2 formed in the flange 24A is not limited to multiple, as long as there is one or more. For improving measurement accuracy, it is preferable to have two or more holes 24H2 in the flange 24A. Additionally, if the grinding wheel 21C is not a hollow annulus, or if a portion of the grinding wheel seat overlaps with the hole 24H2, a hole communicating with the hole 24H2 may also be formed in the grinding wheel 21C.

[0072] When machining workpiece W using the machining apparatus 1A configured in this way, after workpiece W is held in the chuck 31, according to the command from the control device 8, the chuck 31 rotates, the spindle 22 rotates, and the feed mechanism 23 descends (see reference). Figure 12 The grinding wheel 21b, which rotates and descends appropriately, contacts the outer edge W_O of the rotating workpiece W, thereby machining the workpiece W. Figure 13 At this time, such as Figure 14 As shown, the measuring unit 9A can indirectly measure the machining state of the workpiece W near the workpiece being machined (ground) via the hole 24H2 of the flange 24A. The machining apparatus 1A, using the data measured by the measuring unit 9A, measures the machining state of the workpiece W while simultaneously cutting into the workpiece W along the thickness direction by a predetermined amount to grind the outer edge W_O of the workpiece W. Furthermore, as... Figure 15 As shown, it can also be used with Figure 13 The spindle 22 is positioned close to the hole 24H2 of the flange 24A, and the measuring unit 9A is also close to the spindle 22. Thus, the measuring unit 9A measures the machining state of the outer edge W_O of the workpiece W at a position separate from the grinding position where the workpiece W is ground by the grinding wheel 21b.

[0073] Using the processing apparatus 1A described above, even in situations where the space between two adjacent grinding wheels 21b is narrow, or even when it is impossible to provide an observation through-hole in that space, the grinding state of the workpiece W housed within the area surrounded by the grinding wheels 21b can be observed, just like with processing apparatus 1. Furthermore, depending on the position of the hole 24H2 and the shape of the grinding wheel 21C, the processing state of the workpiece W can be determined without machining the grinding wheel 21C, thus reducing manufacturing costs, for example, the grinding wheel 21C, which has a higher replacement frequency than the flange 24A.

[0074] (Second variation) Figure 16This is a diagram illustrating the structure of the processing apparatus 1B in the second modification. The processing apparatus 1B may include a measuring unit 9 and a measuring unit 9A, and further include a flange 24B instead of the flange 24. The aforementioned holes 24H1 and 24H2 may be formed in the flange 24B. In the second modification, the measuring unit 9 can be interpreted as the first measuring unit of this disclosure, and the measuring unit 9A can be interpreted as the second measuring unit of this disclosure. The measuring unit 9A can be interpreted as a sensor having the same function as the measuring unit 9, preferably an optical sensor.

[0075] Figure 17 This is a flowchart illustrating the operation of processing device 1B. Figure 5 The difference in the flowchart shown is that steps S41 and S42 have been added to replace step S4. The other steps are the same as described above, therefore their descriptions are omitted.

[0076] The processing apparatus 1B uses a first measuring unit (measuring unit 9) to measure the state of the outer edge W_O of the workpiece W being ground by the grinding wheel 21b. It further uses a second measuring unit (measuring unit 9A), different from the first measuring unit, to measure the state of the portion of the workpiece W inside the outer edge W_O via a hole 24H2 formed in the region of the flange 24B, which is inside the grinding wheel 21b (S41). The processing apparatus 1B uses the measurement results from both the first and second measuring units to measure the thickness of the outer edge W_O of the workpiece W (S42). For example, the measurement result from the second measuring unit can use the surface of the unground workpiece W as a reference, and the measurement result from the first measuring unit can measure the state of the outer edge W_O of the actually ground workpiece W. Therefore, both sensors can be used as displacement sensors to measure the actual thickness of the workpiece W.

[0077] By using the processing apparatus 1B described above, multiple different measuring units are combined to measure the state of the workpiece W, thereby enabling high-precision measurement of the displacement (actual thickness) of the workpiece W during cutting. Furthermore, by combining the measurement results from the first measuring unit (measuring unit 9) with the measurement results from the second measuring unit (measuring unit 9A), even when there is water for grinding on the surface of the workpiece W, the displacement of the portion cut off by the grinding wheel 21b can be measured with high precision, using the uncut portion of the workpiece W, i.e., the portion measured by the second measuring unit (measuring unit 9A), as a reference. Additionally, by using a temperature sensor as the second measuring unit to measure the temperature of the workpiece W during processing, and using an infrared sensor as the first measuring unit to measure the state of the outer edge W_O of the workpiece W actually being ground, the temperature of the workpiece W can be managed while controlling the processing of the workpiece W.

[0078] (3rd variation) Figure 18 This is a diagram showing a structural example of the processing apparatus 1C in the third modified example. The processing apparatus 1C can, in addition to... Figure 1 In addition to the structure shown, it also includes a measuring unit 9B and a support member 33. In the third variation, the measuring unit 9 can be interpreted as the first measuring unit of this disclosure, and the measuring unit 9B can be interpreted as the third measuring unit of this disclosure. The measuring unit 9B can be interpreted as a sensor having the same function as the measuring unit 9, preferably an optical sensor. The measuring unit 9B can be fixed, for example, to the support member 33 extending vertically from the tilting table 32c. The measuring unit 9B can measure, in a non-contact manner, a reference position that serves as a reference for measuring the thickness of the workpiece W, such as the position in the Z-axis direction of the chuck 31. Furthermore, the installation position of the measuring unit 9B is not limited to the example shown, as long as it is a position that can measure the aforementioned reference position. In addition, the mounting part of the measuring unit 9B can be, for example, the housing 2a of the grinding unit 2, besides the support member 33.

[0079] Figure 19 This is a flowchart illustrating the operation of the processing device 1C. Figure 5 The difference in the flowchart shown is that steps S410 and S420 have been added to replace step S4. The other steps are the same as described above, therefore their descriptions are omitted.

[0080] The machining apparatus 1C uses a first measuring unit (measuring unit 9) to measure the state of the outer edge W_O of the workpiece W being ground by the grinding wheel 21b, and further uses a third measuring unit (measuring unit 9B), which is different from the first measuring unit (measuring unit 9), to measure the state of the chuck 31 located outside the workpiece W (S410). The machining apparatus 1C uses the measurement results of the first measuring unit and the third measuring unit to measure the thickness of the outer edge W_O of the workpiece W (S420). For example, the measurement result of the third measuring unit includes a reference position in terms of measuring the thickness of the workpiece W, and the measurement result of the first measuring unit can measure the state of the outer edge W_O of the workpiece W that is actually being ground, so the two sensors can be used as displacement sensors to measure the actual thickness of the workpiece W.

[0081] By employing the processing apparatus 1C described above, the state of the workpiece W can be measured with high precision by combining multiple different measuring units. Furthermore, since the drilling of the flange 24 can be reduced, the manufacturing cost of the flange 24 can be decreased. Additionally, by using a temperature sensor as a third measuring unit to measure the temperature of the workpiece W during processing, and using an infrared sensor as a first measuring unit to measure the state of the outer edge W_O of the workpiece W being ground, the processing of the workpiece W can be controlled while simultaneously managing its temperature.

[0082] Furthermore, this disclosure describes an example of processing apparatus 1, 1A, 1B, and 1C performing edge trimming on a workpiece W used for bonding wafers; however, processing apparatus 1, 1A, 1B, and 1C can also be used as an apparatus for back-side grinding of workpiece W. Back-side grinding is typically a process in which the entire back side of workpiece W is ground after a circuit pattern has been formed on the front side of workpiece W, thereby thinning the workpiece W.

[0083] Figure 20 This is a diagram showing the structure of the processing device 1D in the fourth modified example. Figure 21 This is a diagram illustrating the machining state of workpiece W performed by machining device 1D. It can be shown as follows: Figure 20 The diameter of the grinding wheel 21b is set to be the same as the diameter of the workpiece W, as shown, or the diameter of the grinding wheel 21b can be set slightly smaller than the diameter of the workpiece W. Thus, as... Figure 21 As shown, the grinding wheel 21b, which rotates and descends appropriately, contacts the entire outer edge W_O of the rotating workpiece W, thereby enabling the grinding of the entire outer edge W_O of the workpiece W in one pass.

[0084] In addition, this disclosure can be implemented in various ways without departing from its spirit.

[0085] Furthermore, all of these changes are included in the technical concept disclosed herein.

[0086] Figure Identification 1. 1A, 1B, 1C, Machining device; 2. Grinding unit; 2a. Housing; 3. Holding device; 4. Column; 8. Control device; 9. 9A, 9B, Measuring unit; 21. 21C. Grinding wheel; 21b. Grinding wheel; 21H. Hole; 22. Spindle; 23. Feed mechanism; 24. 24A. Flange; 24_1. First surface; 24_2. Second surface; 24a. Hole; 24H1, 24H2. Hole; 31. Chuck; 32. Air bearing; 32a. Rotor; 32b. Stator; 32c. Tilting table; 33. Support component; 81. Processor; 81a. Removal unit; 81b. Status measuring unit; 81c. Adjustment unit; 82. Memory; 83. Storage device; 84. Communication interface; 85. Power supply.

Claims

1. A determination method, wherein, The determination method includes: In the removal process, the grinding wheel, which is connected to a rotatable flange and is opposite to the outer edge of the workpiece, is driven into the workpiece along the thickness direction of the workpiece, which is housed in the area surrounded by the grinding wheel in a top view, thereby grinding away the outer edge of the workpiece. as well as In the first measurement step, the state of the outer edge of the workpiece being ground by the grinding wheel in the removal step is measured using the first measurement unit.

2. The determination method according to claim 1, wherein, The grinding wheel performs grinding in such a way that a portion of its periphery contacts the outer edge.

3. The determination method according to claim 2, wherein, The first measuring unit measures the state of the outer edge portion via a hole through which the flange passes.

4. The determination method according to claim 3, wherein, The first measuring unit measures the state of the outer edge portion via the hole formed between two adjacent grinding wheels in the grinding wheel.

5. The determination method according to claim 3, wherein, The first measuring unit measures the state of the outer edge portion via a hole formed in the region of the flange that is closer to the inside of the grinding wheel.

6. The determination method according to claim 3, wherein, The first measuring unit measures the state of the outer edge portion via a hole through which the flange and the grinding wheel pass.

7. The determination method according to claim 3, wherein, The determination method includes: The second measurement step involves using a second measurement unit, which is different from the first measurement unit, to measure the state of the workpiece that is inside the outer edge of the workpiece via the hole formed in the region of the flange that is inside the grinding wheel. as well as In the thickness measurement process, the thickness of the outer edge is measured using the measurement results of the first measurement process and the second measurement process, respectively.

8. The determination method according to claim 1, wherein, The determination method includes: In the third measurement step, a third measurement unit, different from the first measurement unit, is used to measure the state of the holding part that holds the workpiece, which is located on the outer side of the workpiece. as well as The thickness measurement process uses the measurement results of the first measurement process and the third measurement process to measure the thickness of the outer edge.

9. The determination method according to claim 1, wherein, In the first measurement step, an optical sensor is used as the first measurement unit to measure the state of the outer edge of the workpiece. The optical sensor irradiates light onto the outer edge of the workpiece through a hole, which penetrates from a first surface of the flange on the workpiece side toward a second surface of the grinding wheel on the side opposite to the first surface.

10. The determination method according to claim 1, wherein, The measurement method includes an adjustment step, which, based on the measurement results of the first measurement step, performs at least one of shaping and dressing the grinding wheel to form its shape and sharpening the grinding wheel to make it sharp.

11. The determination method according to claim 2, wherein, A portion around the grinding wheel includes the radially inner side surface of the grinding wheel.

12. A processing apparatus for grinding away the outer edge of a workpiece, wherein, The processing apparatus includes a grinding wheel and a first measuring unit. The grinding wheel is connected to a rotatable flange and faces the outer edge of the workpiece. The first measuring unit measures the state of the workpiece. The processing device grinds the outer edge of the workpiece by causing the grinding wheel to cut into it along the thickness direction of the workpiece housed in the area surrounded by the grinding wheel when viewed from above. The first measuring unit measures the state of the outer edge of the workpiece being ground by the grinding wheel.

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