Method for adjusting the thickness of a protective component

Abstract

The present invention provides a method for adjusting the thickness of a protective member, which suppresses unevenness in the thickness of a wafer including the protective member. A height gauge of a grinding device is used to measure the thickness of the wafer including the protective member at at least three points, and the tilt relationship between the film holding surface of a stage and the wafer holding surface of a holding unit in a protective member forming device is adjusted based on the difference in the thicknesses measured at the three points, i.e., the thickness difference, to improve the parallelism between the film holding surface and the wafer holding surface. As a result, when the protective member is formed on the wafer in the protective member forming device, unevenness in the thickness of the wafer including the protective member can be suppressed.

Description

Technical Field

[0001] This invention relates to a method for adjusting the thickness of protective components. Background Technology

[0002] A circular, plate-shaped pre-cut wafer can be obtained, for example, by slicing a cylindrical silicon ingot using a wire dicing machine. This circular, plate-shaped pre-cut wafer has warpage and irregularities. The pre-cut wafer is then ground using a grinding wheel to remove the warpage and irregularities, and to adjust the thickness of the pre-cut wafer to a specified thickness.

[0003] During the grinding of the original diced wafer, liquid resin is spread on one surface of the wafer and then hardened. This forms a protective component made of resin on one surface of the original diced wafer.

[0004] Regarding the formation of the protective component, for example, it is disclosed in Patent Document 1. In the technology of that document, a film is held using a film holding surface on the upper surface of a stage. Liquid resin is provided onto the film, and pressure is applied from above the liquid resin to the lower surface of the wafer, whose upper surface is held on the wafer holding surface. Furthermore, a load is applied to the liquid resin through the lower surface of the wafer, pushing the liquid resin across the entire surface of the lower surface of the wafer. The pushed-away liquid resin is then hardened to form the protective component.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2017-220548

[0006] In the technology described in Patent Document 1, in order to make the thickness of the wafer, including the protective component, uniform, the film holding surface for holding the film and the wafer holding surface for holding the wafer are adjusted to be parallel to each other. However, sometimes the thickness of the wafer, including the protective component, is uneven due to slight misalignment between the film holding surface and the wafer holding surface, or misalignment of the liquid resin supply position on the film with the center of the wafer. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide a method for adjusting the thickness of a protective component, which can suppress thickness non-uniformity of the wafer including the protective component.

[0008] According to the present invention, a method for adjusting the thickness of a protective component is provided. The protective component forming apparatus and a grinding apparatus are used to adjust the thickness of the protective component. The protective component forming apparatus has a stage and a holding unit. The stage has a film holding surface for holding a film, and the holding unit has a wafer holding surface for holding a wafer. One side of the wafer held by the wafer holding surface is pressed against liquid resin provided on the film held by the film holding surface, thereby pushing the liquid resin across the entire surface of that one side of the wafer and hardening the liquid resin, thereby forming a protective component across the entire surface of that one side of the wafer. The protective component is composed of resin obtained by hardening the liquid resin and the film. The grinding apparatus calculates the thickness of the protective component by measuring the height of the holding surface and the upper surface height of the wafer held on the holding surface using a height gauge on the side of the wafer held by the holding surface, with the protective component in between. The thickness of the wafer is adjusted by grinding the wafer with a grinding tool. The method for adjusting the thickness of the protective component includes the following steps: a protective component forming step, in which a protective component is formed on the entire surface of one side of the wafer using a protective component forming apparatus; a thickness calculation step, in which the protective component is held by the holding surface of the grinding apparatus, and the thickness of the wafer, including the protective component, is calculated at at least three locations on the circumference centered on the center of the wafer using a height gauge; a calculation step, in which one of the at least three thickness values ​​calculated by the thickness calculation step is used as a reference value, and the difference between the reference value and the other two thickness values ​​is calculated as the thickness difference; and a tilt adjustment step, in which the tilt relationship between the film holding surface of the stage in the protective component forming apparatus and the wafer holding surface of the holding unit is adjusted using the thickness difference calculated by the calculation step before the protective component is formed.

[0009] The preferred method for adjusting the thickness of the protective component further includes a peeling step: after the thickness calculation step or the tilt adjustment step, the protective component is peeled off from the wafer using a peeling device. The preferred method for adjusting the thickness of the protective component repeatedly performs the protective component formation step, the thickness calculation step, the calculation step, the tilt adjustment step, and the peeling step.

[0010] In this thickness adjustment method, a height gauge of a grinding apparatus is used to calculate the thickness of the wafer, including the protective component, at at least three locations. The tilt relationship between the film holding surface of the stage and the wafer holding surface of the holding unit in the protective component forming apparatus is adjusted based on the thickness difference calculated at these three locations, thereby improving the parallelism between the film holding surface and the wafer holding surface. Therefore, when a protective component is formed on a wafer in the protective component forming apparatus, thickness non-uniformity of the wafer including the protective component can be suppressed. Attached Figure Description

[0011] Figure 1 This is a perspective view showing one embodiment of a wafer manufacturing apparatus.

[0012] Figure 2 This is a perspective view showing the structure of the protective component forming apparatus in a wafer manufacturing device.

[0013] Figure 3 This is an explanatory diagram showing the process of forming the protective component.

[0014] Figure 4 This is a partial cross-sectional side view showing the process of forming the protective component.

[0015] Figure 5 It is a cross-sectional view of a wafer with protective components.

[0016] Figure 6 This is a perspective view showing the structure of the grinding device in a wafer manufacturing apparatus.

[0017] Figure 7 This is a cross-sectional view showing the thickness calculation process.

[0018] Figure 8 This is a top view showing the thickness calculation process.

[0019] Figure 9 This is a cross-sectional view showing an example of a calculation process.

[0020] Figure 10 This is a side view showing an example of the tilt adjustment process.

[0021] Figure 11 This is a top view showing the relationship between the calculation point of the wafer thickness and the three adjustment axes and the outer diameter of the wafer.

[0022] Figure 12 This is a perspective view showing the structure of a stripping device in a wafer manufacturing apparatus.

[0023] Label Explanation

[0024] 100: Wafer; 101: Front side; 102: Back side; 103: Film; 104: Resin layer; 105: Protective component; 107: Notch; 1: Wafer manufacturing apparatus; 5: Transfer box section; 51: Transfer box; 52: Box stage; 511: Shelf; 512: First opening; 513: Second opening; 2: Protective component forming apparatus; 20: First control unit; 21: First transfer robot; 220: Stage; 221: Film holding surface; 224: Liquid resin; 250: Holding unit; 251: Support structure; 254: Connecting shaft; 255: Adjustment shaft; 253: Wafer holding section; 252: Wafer holding surface; 270: Curing unit; 271: Ultraviolet light; 3: Grinding apparatus; 31: Second transfer robot; 36: Second control unit; 315: First transfer unit; 316: Second transfer unit 350: Rotary cleaning unit; 310: Chuck worktable; 311: Holding surface; 312: Outer frame; 317: Motor; 318: Encoder; 320: Altimeter; 321: First contact; 322: Second contact; 401: Rotation axis; 402: Circumference; 410: Outer frame measurement position; 501: Central axis; 502: Circumference; 411: First calculation position; 412: Second calculation position; 413: Third calculation position; 4: Peeling device; 42: Holding unit; 43: Overall peeling unit; 443: Outer part peeling unit; 420: Arm; 421: Holding pad; 422: Y-axis direction movement unit; 423: Z-axis direction movement unit; 406: Temporary worktable; 460: Plate; 479: Box; T1~T3: Thickness value; ΔT: Thickness difference; ΔS: Adjustment value. Detailed Implementation

[0025] Figure 1 The wafer manufacturing apparatus 1 shown removes deformation elements from a wafer 100 containing deformation elements such as undulations and warping, and manufactures a wafer 100 of a predetermined thickness. This wafer manufacturing apparatus 1 includes: a protective member forming apparatus 2 that forms protective members on the wafer 100; a grinding apparatus 3 that grinds the wafer 100; and a stripping apparatus 4 that strips the protective members from the wafer 100. The protective member forming apparatus 2, the grinding apparatus 3, and the stripping apparatus 4 are arranged in an X-direction configuration.

[0026] Furthermore, the wafer manufacturing apparatus 1 has a transfer box 5 for transferring the wafer 100 from the protective component forming apparatus 2 to the grinding apparatus 3. The transfer box 5 is disposed between the protective component forming apparatus 2 and the grinding apparatus 3.

[0027] The wafer 100 is a pre-cut wafer cut from a silicon ingot (hereinafter referred to as the ingot) by a wire dicing machine (not shown). The wafer 100 is formed, for example, in a circular plate shape, having a front side 101 and a back side 102. In addition, a notch 107 is formed on the outer periphery of the wafer 100.

[0028] The back side 102 and the front side 101 of the wafer 100 are examples of one side and the other side of the wafer 100, respectively.

[0029] The protective component forming apparatus 2 forms a protective component containing a resin layer on the entire surface of the back side 102 of the wafer 100. The protective component forming apparatus 2 includes a first transfer robot 21, which houses the wafer 100 with the protective component in the transfer box 5.

[0030] The junction box section 5 has a junction box 51 that holds the wafer 100 in a shelf-like shape and a box platform 52 for placing the junction box 51. The junction box 51 has a plurality of shelves 511 for holding the wafer 100. The shelves 511 are arranged to pass through the junction box 51 from the protective component forming apparatus 2 side to the grinding apparatus 3 side, and have a first opening 512 on the protective component forming apparatus 2 side and a second opening 513 on the grinding apparatus 3 side for the wafer 100 to enter and exit relative to the shelf 511.

[0031] The first transport robot 21 of the protective component forming apparatus 2 stores the chip 100 with the protective component on the shelf 511 of the transfer box 51 through the first opening 512.

[0032] The grinding apparatus 3 grinds the front side 101 and back side 102 of the wafer 100. The grinding apparatus 3 has a second transfer robot 31. The second transfer robot 31 takes the wafer 100 with protective components from the shelf 511 of the transfer box 51 through the second opening 513 and places it in a predetermined position in the grinding apparatus 3. The grinding apparatus 3 has a housing 300, and a loading port 301 for accommodating the wafer 100 whose two sides have been ground is provided on the front surface of the housing 300 in the -Y direction.

[0033] The stripping device 4 strips the protective component from the wafer 100 conveyed by the grinding device 3. The wafer 100 with the protective component stripped is returned to the protective component forming device 2 via the grinding device 3.

[0034] The following describes a method for adjusting the thickness of a protective component, which is one of the operations of the wafer manufacturing apparatus 1.

[0035] The thickness adjustment method for the protective component involved in this embodiment includes a protective component forming process, a thickness calculation process, a calculation process, a tilt adjustment process, and a peeling process.

[0036] [Protective component forming process]

[0037] like Figure 2As shown, the protective component forming apparatus 2 with housing 200 has a first control unit 20 that controls each structure of the protective component forming apparatus 2. The protective component forming apparatus 2 performs the protective component forming process, for example, under the control of the first control unit 20. In the protective component forming process, the protective component forming apparatus 2 is used to form a protective component on the entire surface of the back side 102 of the wafer 100.

[0038] In the protective component forming process, firstly, the first transfer robot 21 takes a wafer 100 from the cassette 201 containing wafers 100 that serve as the original cut wafers and transfers it to the first support stage 202. The wafer detection unit 27 detects the center position and orientation of the wafer 100. Then, the wafer transfer unit 25 removes the wafer 100 from the first support stage 202 and hands it over to the holding unit 250.

[0039] The holding unit 250 has a support structure 251 and a circular plate-shaped wafer holding portion 253 with a wafer holding surface 252. The wafer 100's front surface 101 is attracted and held by the wafer holding surface 252.

[0040] Furthermore, the holding unit 250 has a connecting shaft 254 that supports the center of the wafer holding portion 253 between the support structure 251 and the wafer holding portion 253. The wafer holding portion 253 can move up and down together with the support structure 251 while being supported by the connecting shaft 254.

[0041] Furthermore, the holding unit 250 has three adjustment shafts 255 around the connecting shaft 254 between the support structure 251 and the wafer holding part 253, which serve as a tilt adjustment mechanism. This tilt adjustment mechanism is used to adjust the tilt of the wafer holding surface 252 relative to the support structure 251, i.e., the angular relationship between the wafer holding surface 252 and the film holding surface 221.

[0042] The adjustment shafts 255 are arranged at equal intervals (120 degrees) around the center of the wafer holding surface 252. The adjustment shafts 255 allow for expansion and contraction of the gap between the support structure 251 and the wafer holding portion 253 at the locations where each adjustment shaft 255 is provided. Thus, the three adjustment shafts 255 can adjust the angular relationship between the wafer holding surface 252 and the film holding surface 221.

[0043] In parallel with the transfer of wafer 100 to holding unit 250, the clamping portion 232 of wafer mounting unit 230 clamps a film 103 formed of a transparent material that transmits ultraviolet light and moves it in the Y-axis direction, thereby pulling the film 103 out from roller portion 211. Figure 3As shown, the membrane 103 is placed on the membrane holding surface 221 of a glass stage 220. The membrane holding surface 221 is connected to the attraction source 222 via the attraction path 223. The membrane holding surface 221 uses the attraction force from the attraction source 222 to attract and hold the membrane 103.

[0044] Thus, the protective component forming apparatus 2 includes: a stage 220 having a film holding surface 221; and a holding unit 250 having a wafer holding surface 252.

[0045] after, Figure 2 The resin supply unit 240 shown rotates the resin supply nozzle 241, thereby positioning the supply port 243 of the resin supply nozzle 241 above the stage 220. Then, the dispenser 242 draws in liquid resin, such as UV-curable resin, contained in a resin container (not shown) and delivers it to the resin supply nozzle 241.

[0046] Therefore, as Figure 3 As shown, a predetermined amount of liquid resin 224 is dripped from the resin supply nozzle 241 onto the membrane 103, which is held and attracted by the stage 220.

[0047] Figure 2 The expansion unit 260 shown holds the support structure 251 of the holding unit 250 via a lifting plate 264. The expansion unit 260 rotates the ball screw 261 via a motor 262, thereby causing the holding unit 250 and the lifting plate 264 to descend together. Thus, as... Figure 3 As indicated by the middle arrow 701, the holding unit 250 descends.

[0048] As the holding unit 250 decreases, such as Figure 4 As shown, the back surface 102 of the wafer 100, held by the wafer holding surface 252, is pressed onto the liquid resin 224 provided to the film 103, which is held by the film holding surface 221 of the stage 220. As a result, the liquid resin 224 is pushed across the entire back surface 102 of the wafer 100.

[0049] Below the stage 220 is a curing unit 270, for example, serving as an ultraviolet light source (LED). The curing unit 270 irradiates ultraviolet light 271 onto liquid resin 224 pushed onto the back surface 102 of the wafer 100, across the stage 220. As a result, the liquid resin 244 hardens, forming a resin layer of the hardened resin across the entire back surface 102 of the wafer 100. Then, Figure 2 The expansion unit 260 shown causes the holding unit 250, which holds the wafer 100 via the wafer holding surface 252, to rise together with the lifting plate 264. As a result, the wafer 100 is separated from the stage 220.

[0050] Afterwards, using Figure 2The wafer transport unit 25 shown transports the wafer 100 to the second support stage 203, and uses the film cutter 28 to cut off the excess film 103 along the outline of the wafer 100. At this time, the diameter of the film 103 is slightly larger than the diameter of the wafer 100.

[0051] Thus, as Figure 5 As shown, a protective member 105 is formed on the entire back surface 102 of the wafer 100, consisting of a resin layer 104 (obtained by curing liquid resin 244) and a film 103. After the protective member 105 is formed, the first transport robot 21 transports the wafer 100 with the protective member 105 with its front surface 101 facing upwards via... Figure 1 The first opening 512 shown is stored in the junction box 51.

[0052] After the protective component forming process in the protective component forming apparatus 2, the wafer 100 is processed by the grinding apparatus 3.

[0053] Figure 6 The grinding apparatus 3 shown includes: a chuck stage 310 having a holding surface 311 for holding a wafer 100; a grinding unit 330 for grinding the wafer 100 held on the holding surface 311; and a grinding feed unit 306 for feeding the grinding unit 330. The grinding unit 330 has a grinding wheel 331 having a grinding tool 332.

[0054] Furthermore, the grinding apparatus 3 includes: a rotary cleaning unit 350 for cleaning the ground wafer 100; and a second control unit 36 ​​for controlling each structure of the grinding apparatus 3. The grinding apparatus 3 also includes a height gauge 320 for calculating the thickness of the wafer 100 held by the holding surface 311.

[0055] Furthermore, the grinding apparatus 3 calculates the thickness of the wafer 100, including the protective member 105, using a height gauge 320, while grinding the wafer 100, which is held on the holding surface 311 with respect to the protective member 105, using a grinding tool 332. In the protective member thickness adjustment method of this embodiment, the grinding apparatus 3 performs a thickness calculation process and a calculation process.

[0056] [Thickness Calculation Process]

[0057] In the thickness calculation process, the grinding apparatus 3 calculates the thickness of the wafer 100 to which the protective member 105 is formed, that is, the thickness of the wafer 100 including the protective member 105 (the thickness obtained by adding the thickness of the protective member 105 to the thickness of the wafer 100 alone). In addition, hereafter, the thickness of the wafer 100 including the protective member 105 will sometimes be simply referred to as the thickness of the wafer 100.

[0058] In this process, firstly, the second transfer robot 31 removes the wafer 100 with protective component 105 from the transfer box 5 through the second opening 513. The second transfer robot 31 then places the wafer 100 on its front side 101 (see reference). Figure 5 It is placed on the temporary workbench 32 with its orientation upwards.

[0059] Then, the first transport unit 315 attracts and holds the front side 101 of the wafer 100 and transports it to the chuck stage 310. The chuck stage 310 attracts and holds the protective member 105 formed on the back side 102 of the wafer 100 through the holding surface 311. Thus, as Figure 7 As shown, the chip 100 is held on the chuck stage 310 with its front side 101 exposed.

[0060] Then, the second control unit 36 ​​calculates the thickness of the wafer 100 at at least three locations on the circumference centered on the center of the wafer 100 using the altimeter 320.

[0061] The height gauge 320 contacts the first contact 321 and the second contact 322, which are coplanar with the holding surface 311 of the chuck stage 310 and the front surface 101 of the wafer 100, respectively. Thus, the height gauge 320 can measure the height of the holding surface 311 of the chuck stage 310 and the height of the wafer 100. The height gauge 320 can calculate the thickness of the wafer 100 based on the difference between the measured height of the holding surface 311 and the height of the wafer 100.

[0062] And, as this Figure 7 and Figure 6 As shown, below the chuck stage 310 are: a motor 317 serving as a rotation unit, which rotates the chuck stage 310; and an encoder 318 for detecting the rotation angle of the motor 317, i.e., the rotation angle of the chuck stage 310. The chuck stage 310 rotates about a rotation axis 401 passing through the center of the holding surface 311 and the center of the wafer 100, via the motor 317.

[0063] Furthermore, in the thickness calculation process of the grinding apparatus 3, the second control unit 36 ​​rotates the chuck table 310 via the motor 317 while calculating the thickness of the wafer 100 via the height gauge 320.

[0064] That is, such as Figure 8As shown, the second control unit 36 ​​rotates the chuck stage 310 while sequentially contacting at least three locations on the circumference 402 centered on the center of the wafer 100, namely the first calculation position 411, the second calculation position 412, and the third calculation position 413. Simultaneously, the second control unit 36 ​​also contacts the first contact 321 of the height gauge 320 with the outer frame measurement position 410 on the outer frame 312 of the chuck stage 310, located outside each calculation position 411-413.

[0065] Therefore, the second control unit 36 ​​calculates three thickness values ​​of the wafer 100 related to the first calculation position 411, the second calculation position 412, and the third calculation position 413. Hereinafter, the thickness values ​​of the wafer 100 related to the first calculation position 411, the second calculation position 412, and the third calculation position 413 will be referred to as the first thickness value T1, the second thickness value T2, and the third thickness value T3, respectively.

[0066] [Calculation Process]

[0067] In this calculation process, the second control unit 36 ​​takes one of the three thickness values ​​T1 to T3 calculated in the thickness calculation process as a reference value, and calculates the difference between the reference value and the other two thickness values, i.e., the thickness difference ΔT.

[0068] For example, through a thickness calculation process, a thickness value like the one shown below can be obtained.

[0069] The first thickness value T1 at the first calculation location 411 is 850 μm.

[0070] The second thickness value T2 at the second calculation location 412 is 900 μm.

[0071] The third thickness value T3 at the third calculation location 413 is 900 μm.

[0072] In this case, the second control unit 36, for example, uses the first thickness value T1 (850 μm) as a reference value and calculates 50 μm as the thickness difference ΔT.

[0073] After the calculation process, the second transfer unit 316 attracts and holds the front side 101 of the wafer 100 on the holding surface 311 of the chuck stage 310, and transfers the wafer 100 to the rotary cleaning unit 350.

[0074] [Tilt Adjustment Process]

[0075] In this tilt adjustment process, Figure 2The first control unit 20 of the protective component forming apparatus 2 shown uses the thickness difference ΔT calculated by the calculation process to adjust the tilt relationship between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250 in the protective component forming apparatus 2 before forming the protective component.

[0076] For example, as shown in the example above, the first thickness value T1, which serves as the reference value, is 850 μm, while the second thickness value T2 and the third thickness value T3 are 900 μm, and the thickness difference ΔT is 50 μm.

[0077] In addition, such as Figure 9 As shown, Figure 8 The distance from the rotation axis 401 to the first calculation position 411, the second calculation position 412 and the third calculation position 413 shown is the radius of the circle 402 of the specified calculation positions 411 to 413, which is 124.5 mm.

[0078] and, Figure 2 The three adjusting shafts 255 in the holding unit 250 of the protective component forming device 2 shown are located at intervals of 120 degrees and are positioned at... Figure 10 The wafer holding section 253 shown is centered on a central axis 501 that passes through the center of the wafer holding surface 252. Moreover, the radius of this circumference, that is, the distance between the central axis 501 and the three adjustment axes 255, is 120 mm.

[0079] And, as Figure 11 The relationships between the first calculation position 411, the second calculation position 412, and the third calculation position 413, as three calculation points, and the three adjustment axes 255 and the outer diameter of the wafer 100 are set as shown. Each calculation position 411 to 413 is configured in a manner corresponding to the three adjustment axes 255. Figure 11 In addition to showing the outer diameter of the wafer 100 and the circumference 402 of the specified calculation positions 411 to 413, the circumference 502 of the specified three adjustment axes 255 is also shown.

[0080] In this case, since the radius of the circumference 402 is 124.5 mm and the thickness difference ΔT is 50 μm, the first control unit 20 of the protective component forming apparatus 2 makes the following judgment: the wafer holding surface 252 and the film holding surface 221 deviate from parallel at an angle θ such that tanθ = 50 μm / 124.5 mm.

[0081] Furthermore, in order to adjust this offset, the first control unit 20 uses two adjustment axes 255 corresponding to the second calculation position 412 and the third calculation position 413, such as... Figure 10As shown, the interval between the support structure 251 and the wafer holding part 253 at the part where these adjustment shafts 255 are provided is adjusted according to the adjustment value ΔS.

[0082] In the example above, the distance between the central axis 501 and the three adjustment axes 255 is 120 mm, therefore ΔS is 48.19 μm (120 mm tanθ). That is, the first control unit 20 uses two adjustment axes 255 corresponding to the second calculation position 412 and the third calculation position 413 to extend the interval ΔS between the support structure 251 and the wafer holding part 253 at the setting position of these adjustment axes 255. As a result, the parallelism between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250 can be improved.

[0083] [Stripping Process]

[0084] In this stripping process, using Figure 12 The peeling device 4 shown includes a protective component 105 (see reference 105) comprising a resin layer 104 and a film 103. Figure 5 (etc.) are peeled off from chip 100.

[0085] like Figure 12 As shown, the stripping device 4 has a holding unit 42 for holding and transporting the wafer 100. The holding unit 42 includes: a holding pad 421 for attracting and holding the wafer 100; an arm 420 for supporting the holding pad 421; a Z-axis moving unit 423 for supporting the arm 420 and causing the arm 420 to reciprocate in the Z-axis direction; a movable plate 429 for supporting the Z-axis moving unit 423; and a Y-axis moving unit 422 for causing the movable plate 429 to reciprocate in the Y-axis direction.

[0086] In the peeling device 4, firstly, the holding pad 421 of the holding unit 42 is moved to a position adjacent to the peeling device 4 using the Y-axis moving unit 422 and the Z-axis moving unit 423. Figure 6 The grinding apparatus 3 shown has a rotary cleaning unit 350. Then, the holding pad 421 attracts and holds the front side 101 of the wafer 100 placed in the rotary cleaning unit 350.

[0087] Then, the holding unit 42 places the wafer 100 on the holding stage 441 with its front side 101 facing upwards. The holding stage 441 attracts and holds the wafer 100. Then, the holding stage 441 and the outer portion stripping unit 443 strip the wafer 100 at multiple locations (e.g., 7 locations) only. Figure 5 The outer portion of the protective member 105 of the wafer 100 shown is peeled off from the back surface 102 of the wafer 100. After this peeling, the holding stage 441 is released from its attraction to the wafer 100.

[0088] Next, the holding unit 42 attracts the wafer 100 on the holding stage 441 through the holding pad 421, and transports the wafer 100 to a position above the overall stripping unit 43 and fixes it in that position.

[0089] The overall stripping unit 43 includes a gripping portion 431 and a moving member 432 that moves the gripping portion 431 along the X-axis. The gripping portion 431 grips the stripped outer portion on the -X side of the protective member 105 of the wafer 100. In this state, the moving member 432 moves the gripping portion 431 towards the +X side. Since the position of the wafer 100 is fixed, the protective member 105 is stripped from the back surface 102 of the wafer 100 by the movement of the gripping portion 431 holding the protective member 105. At this time, the guide roller 452 abuts against the lower surface of the protective member 105.

[0090] The stripped protective component 105 is temporarily placed on a temporary stage 406. The temporary stage 406 has a plurality of plates 460 extending along the X-axis. The plurality of plates 460 are arranged at predetermined intervals in the Y-axis direction. Each plate 460 extends in a manner longer than the diameter of the wafer 100 and has a predetermined thickness in the Y-axis direction. In addition, the temporary stage 406 as a whole has a placement area larger than that of the wafer 100.

[0091] Below the temporary worktable 406 is a protective component feeding unit 407 that feeds the protective component 105 placed on the temporary worktable 406 into the box 479. The protective component feeding unit 407 has an arm 470 extending along the Y-axis direction and two pins 471 on the arm 470. The pins 471 extend in a manner that protrudes from the upper surface of the plate 460 of the temporary worktable 406.

[0092] When the arm 470 is moved in the X-axis direction by the actuator 472 driven by the electric motor, the pin 471 protruding from the plate 460 of the temporary worktable 406 also moves in the X-axis direction. As a result, the protective component 105 placed on the temporary worktable 406 falls into the box 479.

[0093] In the housing 479, a pair of optical sensors 480 are provided at the upper part of one of the opposite sides. The optical sensor 480 includes a light-emitting part and a light-receiving part. The light-receiving part of the optical sensor 480 receives light generated from the light-emitting part, and detects whether the protective component 105 recycled into the housing 479 is full based on the change in the amount of light received by the light-receiving part.

[0094] Then, in the stripping device 4, the holding unit 42 transports the wafer 100 to... Figure 6The grinding device 3 shown is placed in the rotary cleaning unit 350 with its front 101 facing upwards. When the wafer 100 is placed in the rotary cleaning unit 350, the second transport robot 31 of the grinding device 3 holds the wafer 100 and stores it on the shelf 511 of the transfer box 51 through the second opening 513.

[0095] Alternatively, the second transfer robot 31 may stand by above the rotary cleaning unit 350, and the holding unit 42 of the peeling device 4 may transfer the wafer 100 to the second transfer robot 31.

[0096] then, Figure 2 The first transfer robot 21 of the protective component forming apparatus 2 shown in the diagram removes the wafer 100 from the shelf 511 of the transfer box 51 via the first opening 512 and places it on the first support stage 202 of the protective component forming apparatus 2. Then, the aforementioned protective component forming process, thickness calculation process, calculation process, tilt adjustment process, and peeling process are repeatedly performed until, for example, the thickness difference ΔT calculated by the calculation process becomes below a predetermined value.

[0097] As described above, in this embodiment, the thickness of the wafer 100, including the protective member 105, is calculated at at least three locations using the height gauge 320 of the grinding apparatus 3. Based on the difference in thickness calculated at these three locations (i.e., the thickness difference), the tilt relationship between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250 in the protective member forming apparatus 2 is adjusted, thereby improving the parallelism between the film holding surface 221 and the wafer holding surface 252. Therefore, when the protective member 105 is formed on the wafer 100 in the protective member forming apparatus 2, thickness non-uniformity of the wafer 100, including the protective member 105, can be suppressed.

[0098] Furthermore, in this embodiment, the protective component formation process, thickness calculation process, calculation process, tilt adjustment process, and stripping process can be performed without the intervention of an operator. This allows for the automation of adjusting the tilt relationship between the film holding surface 221 and the wafer holding surface 252 in the protective component formation apparatus 2. Consequently, it is easier to suppress thickness non-uniformity of the wafer 100, including the protective component 105.

[0099] Furthermore, in this embodiment, the wafer 100, from which the protective component 105 has been removed through the peeling process, is returned to the protective component forming apparatus 2, and the protective component forming process, thickness calculation process, calculation process, tilt adjustment process, and peeling process are repeatedly performed. This improves the accuracy of the adjustment of the tilt relationship between the film holding surface 221 and the wafer holding surface 252. Additionally, since a single wafer 100 is reused, the cost of adjustment can be reduced.

[0100] Furthermore, in this embodiment, the protective component formation process, thickness calculation process, calculation process, tilt adjustment process, and peeling process are repeatedly performed. However, these processes can also be set to be performed only once each without repetition. In this case, the parallelism between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250 can also be improved to a certain extent.

[0101] In this embodiment, the peeling process is performed after the tilt adjustment process. Alternatively, the peeling process can be performed after the thickness calculation process and before the tilt adjustment process, or it can be performed simultaneously with the tilt adjustment process.

[0102] Alternatively, the stripping process may not be performed. In this case, the wafer manufacturing apparatus 1 may not have the stripping device 4. That is, in the thickness adjustment method for the protective component of this embodiment, at least the following is used: Figure 1 The protective component forming apparatus 2 and the grinding apparatus 3 shown are sufficient. In this case, the parallelism between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250 can also be improved.

[0103] Furthermore, in this embodiment, the thickness calculation locations in the thickness calculation process are set to three locations: the first calculation location 411, the second calculation location 412, and the third calculation location. However, the thickness calculation locations in the thickness calculation process can be at least three locations, or more than four locations.

Claims

1. A thickness adjustment method of a protective member, adjusting a thickness of a protective member using a protective member forming device and a grinding device, the protective member forming device having a stage having a film holding surface that holds a film, and a holding unit having a wafer holding surface that holds a wafer, pressing one surface of the wafer held by the wafer holding surface against liquid resin supplied to the film held by the film holding surface to push the liquid resin away over the entire surface of the one surface of the wafer, and hardening the liquid resin, thereby forming a protective member over the entire surface of the one surface of the wafer, the protective member being composed of resin obtained by hardening the liquid resin and the film, the grinding device grinding the wafer held by a holding surface across the protective member while calculating a thickness of the wafer including the protective member based on a value obtained by measuring a height of the holding surface and an upper surface height of the wafer held on the holding surface using a height gauge, wherein the thickness adjustment method of the protective member having the following steps: a protective member forming step of forming a protective member over the entire surface of one surface of a wafer using the protective member forming device; a thickness calculating step of holding the protective member using the holding surface of the grinding device that is a different device from the protective member forming device, and calculating a thickness of the wafer including the protective member at at least three positions on a circumference centered on a center of the wafer using the height gauge of the grinding device; a calculating step of calculating a thickness difference that is a difference between a reference value that is one of the at least three thickness values calculated by the thickness calculating step and the other two thickness values; and a tilt adjusting step of adjusting a tilt relationship between the film holding surface of the stage and the wafer holding surface of the holding unit in the protective member forming device using the thickness difference calculated by the calculating step before a protective member is formed next.

2. The thickness adjustment method of the protective member according to claim 1, wherein the thickness adjustment method of the protective member further has a peeling step of peeling the protective member from the wafer using a peeling device that peels the protective member from the wafer after the thickness calculating step or after the tilt adjusting step, the protective member forming step, the thickness calculating step, the calculating step, the tilt adjusting step, and the peeling step are repeated.

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