阅读说明：本技术 保护部件的厚度调整方法 (Method for adjusting thickness of protective member ) 是由 广内大资 于 2021-05-26 设计创作，主要内容包括：本发明提供保护部件的厚度调整方法,抑制包含保护部件在内的晶片的厚度不均匀。使用磨削装置的高度计,在至少3个部位计算包含保护部件在内的晶片的厚度,根据在该3个部位计算的厚度之差即厚度差来调整保护部件形成装置中的载台的膜保持面与保持单元的晶片保持面的倾斜关系,能够提高膜保持面与晶片保持面的平行度。由此,当在保护部件形成装置中在晶片上形成保护部件时,能够抑制包含保护部件在内的晶片的厚度不均匀。(The invention provides a method for adjusting the thickness of a protective member, which can restrain the thickness unevenness of a wafer including the protective member. The height gauge using the grinding device calculates the thickness of the wafer including the protective member at least 3 locations, and adjusts the inclination relationship between the film holding surface of the stage in the protective member forming device and the wafer holding surface of the holding unit based on the thickness difference, which is the difference between the thicknesses calculated at the 3 locations, thereby improving the parallelism between the film holding surface and the wafer holding surface. Thus, when the protective member is formed on the wafer in the protective member forming apparatus, the thickness unevenness of the wafer including the protective member can be suppressed.)

1. A method for adjusting the thickness of a protective member, which adjusts the thickness of the protective member by using a protective member forming apparatus and a grinding apparatus,

the protective member forming apparatus includes a stage having a film holding surface for holding a film, and a holding unit having a wafer holding surface for holding a wafer, wherein a protective member is formed on an entire surface of the one surface of the wafer by pressing the one surface of the wafer held by the wafer holding surface against a liquid resin supplied to the film held by the film holding surface to push the liquid resin away from the entire surface of the one surface of the wafer and hardening the liquid resin, the protective member being composed of the film and a resin obtained by hardening the liquid resin,

the grinding apparatus grinds a wafer held by a holding surface via a protective member by a grinding wheel while calculating a thickness of the wafer including the protective member from a value obtained by measuring a height of the holding surface and a height of an upper surface of the wafer held by the holding surface using a height meter,

the method for adjusting the thickness of the protective member comprises the following steps:

a protective member forming step of forming a protective member on the entire surface of one surface of the wafer by using the protective member forming apparatus;

a thickness calculating step of calculating the thickness of the wafer including the protective member at least 3 locations on a circumference around the center of the wafer by the height gauge while holding the protective member by the holding surface of the grinding device;

a calculation step of calculating a thickness difference, which is a difference between the reference value and the other 2 thickness values, using 1 of the at least 3 thickness values calculated in the thickness calculation step as a reference value; and

and an inclination adjustment step of adjusting an inclination relationship between the film holding surface of the stage and the wafer holding surface of the holding unit in the protective member forming apparatus before forming a protective member next, using the thickness difference calculated in the calculation step.

2. The method for adjusting thickness of a protective member according to claim 1,

the method for adjusting the thickness of the protective member further comprises the following peeling step: peeling the protective member from the wafer using a peeling device for peeling 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 inclination adjusting step, and the peeling step are repeated.

Technical Field

The present invention relates to a method for adjusting the thickness of a protective member.

Background

The circular plate-shaped raw sliced wafer can be obtained by slicing a cylindrical silicon ingot by a wire saw, for example. The original cut wafer in the form of a circular plate has warpage and undulation. The raw cut wafer is ground by a grinding wheel to remove warpage and undulation from the raw cut wafer and to adjust the thickness of the raw cut wafer to a prescribed thickness.

When grinding the original dicing wafer, a liquid resin is pushed away on one surface of the original dicing wafer and hardened. Thus, a protective member made of resin is formed on one surface of the original dicing wafer.

The formation of the protective member is disclosed in patent document 1, for example. In the technique of this document, a film is held by a film holding surface on the upper surface of a stage. A liquid resin is supplied onto the film, and the lower surface of the wafer, the upper surface of which is held by the wafer holding surface, is pressed from above the liquid resin. Further, a load is applied to the liquid resin through the lower surface of the wafer, and the liquid resin is pushed away over the entire lower surface of the wafer. The liquid resin pushed away is hardened to form a protective member.

Patent document 1: japanese patent laid-open publication No. 2017-220548

In the technique described in patent document 1, in order to make the thickness of the wafer including the protective member uniform, a film holding surface for holding the film and a wafer holding surface for holding the wafer are adjusted to be parallel to each other. However, the thickness of the wafer including the protective member may be uneven due to the film holding surface being slightly non-parallel to the wafer holding surface, or the supply position of the liquid resin on the film not matching the center of the wafer.

Disclosure of Invention

Therefore, an object of the present invention is to provide a method for adjusting the thickness of a protective member, which can suppress the thickness unevenness of a wafer including the protective member.

According to the present invention, there is provided a method of adjusting a thickness of a protective member, the method comprising adjusting the thickness of the protective member using a protective member forming apparatus and a grinding apparatus, the protective member forming apparatus comprising a stage having a film holding surface for holding a film, and a holding unit having a wafer holding surface for holding a wafer, wherein one surface of the wafer held by the wafer holding surface is pressed against a liquid resin supplied onto 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 the liquid resin is hardened, thereby forming a protective member over the entire surface of the one surface of the wafer, the protective member being composed of a resin obtained by hardening the liquid resin and the film, and the grinding apparatus measuring a height of the holding surface and a height of an upper surface of the wafer held by the holding surface via the protective member on the basis of a height of a use level, while measuring the height of the wafer held by the holding surface via the protective member, and the height of the upper surface of the wafer held by the holding surface And calculating the thickness of the wafer including the protective member from the obtained value, and grinding the wafer by a grinding wheel, wherein the method for adjusting the thickness of the protective member comprises the following steps: a protective member forming step of forming a protective member on the entire surface of one surface of the wafer by using the protective member forming apparatus; a thickness calculating step of calculating the thickness of the wafer including the protective member at least 3 locations on a circumference around the center of the wafer by the height gauge while holding the protective member by the holding surface of the grinding device; a calculation step of calculating a thickness difference, which is a difference between the reference value and the other 2 thickness values, using 1 of the at least 3 thickness values calculated in the thickness calculation step as a reference value; and an inclination adjustment step of adjusting an inclination relationship between the film holding surface of the stage and the wafer holding surface of the holding unit in the protective member forming apparatus before forming a protective member next, using the thickness difference calculated in the calculation step.

Preferably, the method for adjusting the thickness of the protective member further comprises the following peeling step: after the thickness calculating step or after the tilt adjusting step, the protective member is peeled from the wafer using a peeling device that peels the protective member from the wafer. Preferably, the method for adjusting the thickness of the protective member repeats the protective member forming step, the thickness calculating step, the inclination adjusting step, and the peeling step.

In the thickness adjusting method, the thickness of the wafer including the protective member is calculated at least 3 locations using the height gauge of the grinding device, and the inclination relationship between the film holding surface of the stage in the protective member forming device and the wafer holding surface of the holding unit is adjusted based on the thickness difference, which is the difference between the thicknesses calculated at the 3 locations, thereby making it possible to improve the parallelism between the film holding surface and the wafer holding surface. Thus, when the protective member is formed on the wafer in the protective member forming apparatus, the thickness unevenness of the wafer including the protective member can be suppressed.

Drawings

Fig. 1 is a perspective view showing a wafer manufacturing apparatus according to an embodiment.

Fig. 2 is a perspective view showing the structure of a protective member forming apparatus in the wafer manufacturing apparatus.

Fig. 3 is an explanatory diagram illustrating a protective member forming process.

Fig. 4 is a side view, partly in section, showing a protective member forming process.

Fig. 5 is a cross-sectional view of a wafer with a protective member.

Fig. 6 is a perspective view showing the structure of a grinding apparatus in the wafer manufacturing apparatus.

Fig. 7 is a cross-sectional view showing a thickness calculation process.

Fig. 8 is a plan view showing a thickness calculation process.

Fig. 9 is a cross-sectional view showing an example of the calculation process.

Fig. 10 is a side view showing an example of the tilt adjusting process.

Fig. 11 is a plan view showing the relationship between the calculated point of the thickness of the wafer and the 3 adjustment axes and the outer diameter of the wafer.

Fig. 12 is a perspective view showing the structure of a peeling apparatus in the wafer manufacturing apparatus.

Description of the reference symbols

100: a wafer; 101: a front side; 102: a back side; 103: a film; 104: a resin layer; 105: a protective member; 107: a recess; 1: a wafer manufacturing apparatus; 5: a transfer box section; 51: a cross-connecting box; 52: a box loading platform; 511: a shelf; 512: 1 st opening; 513: a 2 nd opening; 2: a protective member forming device; 20: a 1 st control unit; 21: 1 st transfer robot; 220: a stage; 221: a film holding face; 224: a liquid resin; 250: a holding unit; 251: a support structure; 254: a connecting shaft; 255: an adjustment shaft; 253: a wafer holding section; 252: a wafer holding surface; 270: a hardening unit; 271: ultraviolet light; 3: a grinding device; 31: 2 nd transfer robot; 36: a 2 nd control part; 315: a 1 st conveying unit; 316: a 2 nd conveying unit; 350: a rotary cleaning unit; 310: a chuck table; 311: a holding surface; 312: an outer frame; 317: an electric motor; 318: an encoder; 320: an altimeter; 321: a 1 st contact; 322: a 2 nd contact; 401: a rotating shaft; 402: a circumference; 410: measuring the position of the outer frame; 501: a central shaft; 502: a circumference; 411: 1, calculating a position; 412: computing a position; 413: calculating the position; 4: a peeling device; 42: a holding unit; 43: an integral peeling unit; 443: an outer part peeling unit; 420: an arm portion; 421: a holding pad; 422: a Y-axis direction moving unit; 423: a Z-axis direction moving unit; 406: temporarily placing a workbench; 460: a plate; 479: a tank; T1-T3: a thickness value; Δ T: thickness difference; Δ S: and adjusting the value.

Detailed Description

The wafer manufacturing apparatus 1 shown in fig. 1 removes a deformation element from a wafer 100 including the deformation element represented by undulation, warpage, or the like, and manufactures the wafer 100 having a predetermined thickness. The wafer manufacturing apparatus 1 includes: a protective member forming apparatus 2 that forms a protective member on the wafer 100; a grinding device 3 for grinding the wafer 100; and a peeling device 4 which peels the protective member from the wafer 100. The protective member forming device 2, the grinding device 3, and the peeling device 4 are arranged in the X direction.

The wafer manufacturing apparatus 1 further includes a delivery cassette unit 5 for transferring the wafer 100 from the protective member forming apparatus 2 to the grinding apparatus 3. The delivery box section 5 is disposed between the protective member forming apparatus 2 and the grinding apparatus 3.

The wafer 100 is an as-sliced wafer cut out from a silicon ingot (hereinafter, simply referred to as an ingot) by a wire saw (not shown). The wafer 100 is formed in a disk shape, for example, and has a front surface 101 and a back surface 102. Further, a notch 107 is formed in the outer periphery of the wafer 100.

The back surface 102 and the front surface 101 of the wafer 100 correspond to one surface and the other surface of the wafer 100, respectively.

The protective member forming apparatus 2 forms a protective member including a resin layer on the entire back surface 102 of the wafer 100. The protective member forming apparatus 2 includes a 1 st transfer robot 21, and the 1 st transfer robot 21 stores the wafer 100 having the protective member in the delivery cassette section 5.

The delivery cassette unit 5 includes a delivery cassette 51 for storing the wafer 100 in a shelf shape and a cassette stage 52 on which the delivery cassette 51 is placed. The pod 51 has a plurality of shelves 511 for receiving the wafers 100. The shelf 511 is provided so as to penetrate the delivery cassette 51 from the side of the protective member forming apparatus 2 to the side of the grinding apparatus 3, and has a 1 st opening 512 on the side of the protective member forming apparatus 2 for allowing the wafer 100 to enter and exit from the shelf 511 and a 2 nd opening 513 on the side of the grinding apparatus 3.

The 1 st transfer robot 21 of the protective member forming apparatus 2 stores the wafer 100 having the protective member on the shelf 511 of the delivery cassette 51 through the 1 st opening 512.

The grinding device 3 grinds the front surface 101 and the back surface 102 of the wafer 100. The grinding device 3 includes a 2 nd transfer robot 31. The 2 nd transfer robot 31 takes out the wafer 100 having the protective member from the shelf 511 of the delivery cassette 51 through the 2 nd opening 513, and places the wafer at a predetermined position in the grinding apparatus 3. The grinding apparatus 3 includes a housing 300, and a load port 301 for storing the wafer 100 whose both surfaces have been ground is provided on the front surface of the housing 300 on the-Y direction side.

The peeling device 4 peels the protective member from the wafer 100 conveyed by the grinding device 3. The wafer 100 from which the protective member is peeled is returned to the protective member forming apparatus 2 via the grinding apparatus 3.

A method of adjusting the thickness of the protective member for adjusting the thickness of the protective member, which is one of the operations of the wafer manufacturing apparatus 1, will be described below.

The method for adjusting the thickness of a protective member according to the present embodiment includes a protective member forming step, a thickness calculating step, a calculating step, an inclination adjusting step, and a peeling step.

[ protective Member Forming Process ]

As shown in fig. 2, the protective member forming apparatus 2 having the casing 200 includes a 1 st control unit 20 that controls each configuration of the protective member forming apparatus 2. The protective member forming apparatus 2 performs a protective member forming process under the control of the 1 st control unit 20, for example. In the protective member forming step, a protective member is formed on the entire back surface 102 of the wafer 100 using the protective member forming apparatus 2.

In the protective member forming step, first, the 1 st transfer robot 21 takes out one wafer 100 from the cassette 201 in which the wafers 100 as the original diced wafers are stored, and transfers the wafer to the 1 st support table 202. The wafer detection section 27 detects the center position and orientation of the wafer 100. Then, the wafer carrier 25 carries the wafer 100 out of the 1 st support base 202 and delivers it to the holding unit 250.

The holding unit 250 has a support structure 251 and a disk-shaped wafer holding portion 253 having a wafer holding surface 252. The front surface 101 of the wafer 100 is sucked and held by the wafer holding surface 252.

The holding unit 250 further includes a coupling shaft 254 that supports the center of the wafer holder 253 between the support structure 251 and the wafer holder 253. The wafer holding portion 253 can be lifted and lowered together with the support structure 251 in a state of being supported by the coupling shaft 254.

The holding unit 250 further includes 3 adjustment shafts 255 as a tilt adjustment mechanism for adjusting the tilt of the wafer holding surface 252 with respect to the supporting structure 251, that is, the angular relationship between the wafer holding surface 252 and the film holding surface 221, around the coupling shaft 254 between the supporting structure 251 and the wafer holding portion 253.

The adjustment shafts 255 are provided at regular intervals, i.e., at intervals of 120 degrees, on a circumference around the center of the wafer holding surface 252. The adjustment shafts 255 can expand and contract the gap between the support structure 251 and the wafer holder 253 at the portion where each adjustment shaft 255 is provided. Thus, the 3 adjustment shafts 255 can adjust the angular relationship between the wafer holding surface 252 and the film holding surface 221.

In parallel with the transfer of the wafer 100 to the holding unit 250, the film 103 formed of a transparent material that transmits ultraviolet rays is pulled out from the roller portion 211 by the clamping portion 232 of the sheet placing unit 230 clamping the film 103 and moving in the Y-axis direction. As shown in fig. 3, the film 103 is placed on a film holding surface 221 of a glass stage 220. The film holding surface 221 communicates with the suction source 222 via the suction passage 223. The film holding surface 221 attracts and holds the film 103 using a suction force from the attraction source 222.

In this way, the protective member forming apparatus 2 includes: a stage 220 having a film holding surface 221; and a holding unit 250 having a wafer holding surface 252.

After that, the resin supply unit 240 shown in fig. 2 rotates the resin supply nozzle 241, thereby positioning the supply port 243 of the resin supply nozzle 241 above the stage 220. Next, the dispenser 242 sucks liquid resin, for example, ultraviolet curable resin, contained in a resin container (not shown), and sends the resin to the resin supply nozzle 241.

As a result, as shown in fig. 3, a predetermined amount of liquid resin 224 is dropped from resin supply nozzle 241 onto film 103 sucked and held by stage 220.

The extension unit 260 shown in fig. 2 holds the support structure 251 of the holding unit 250 by the lifting plate 264. The expansion unit 260 rotates the ball screw 261 by the motor 262, thereby lowering the holding unit 250 together with the lifting plate 264. Thereby, the holding unit 250 descends as indicated by an arrow 701 in fig. 3.

As the holding unit 250 descends, as shown in fig. 4, the back surface 102 of the wafer 100 sucked and held by the wafer holding surface 252 is pressed against the liquid resin 224 supplied to the film 103 sucked and held by the film holding surface 221 of the stage 220. Thereby, the liquid resin 224 is pushed away over the entire back surface 102 of the wafer 100.

A curing unit 270, for example, an ultraviolet light source (LED) is provided below the stage 220. The curing unit 270 irradiates ultraviolet light 271 toward the liquid resin 224 pushed away on the back surface 102 of the wafer 100 via the stage 220. As a result, the liquid resin 244 is cured, and a resin layer made of the cured resin is formed on the entire back surface 102 of the wafer 100. Then, the expanding unit 260 shown in fig. 2 raises the holding unit 250 holding the wafer 100 by the wafer holding surface 252 together with the elevating plate 264. Thereby, the wafer 100 is separated from the stage 220.

Thereafter, the wafer 100 is transferred onto the 2 nd support table 203 by the wafer transfer unit 25 shown in fig. 2, and the excess film 103 is cut along the outer shape of the wafer 100 by the film cutter 28. At this time, the diameter of the film 103 is slightly larger than the diameter of the wafer 100.

As shown in fig. 5, the protective member 105 including the resin layer 104 and the film 103, which are resins obtained by curing the liquid resin 244, is formed on the entire back surface 102 of the wafer 100. After the protective member 105 is formed, the 1 st transfer robot 21 receives the wafer 100 having the protective member 105 into the delivery cassette 51 through the 1 st opening 512 shown in fig. 1 such that the front surface 101 faces upward.

After the protective member forming process of the protective member forming apparatus 2, the wafer 100 is processed by the grinding apparatus 3.

The grinding apparatus 3 shown in fig. 6 has: a chuck table 310 having a holding surface 311 for holding the wafer 100; a grinding unit 330 that grinds the wafer 100 held on the holding surface 311; and a grinding feed unit 306 for grinding-feeding the grinding unit 330. The grinding unit 330 has a grinding wheel 331, and the grinding wheel 331 has a grinding wheel 332.

The grinding device 3 further includes: a spin cleaning unit 350 for cleaning the ground wafer 100; and a 2 nd control unit 36 for controlling the respective configurations of the grinding device 3. The grinding apparatus 3 further includes a height meter 320 for calculating the thickness of the wafer 100 held by the holding surface 311.

The grinding apparatus 3 grinds the wafer 100 held on the holding surface 311 via the protective member 105 by the grinding whetstone 332 while calculating the thickness of the wafer 100 including the protective member 105 by using the height gauge 320. In the method for adjusting the thickness of the protective member according to the present embodiment, the grinding device 3 performs a thickness calculation step and a calculation step.

[ procedure for calculating thickness ]

In the thickness calculation step, the grinding apparatus 3 calculates the thickness of the wafer 100 on 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 only the wafer 100). Hereinafter, the thickness of the wafer 100 including the protective member 105 may be simply referred to as the thickness of the wafer 100.

In this step, first, the 2 nd transfer robot 31 takes out the wafer 100 having the protective member 105 in the delivery cassette part 5 through the 2 nd opening 513. The 2 nd transfer robot 31 places the wafer 100 on the temporary placement table 32 with the front surface 101 (see fig. 5) facing upward.

Then, the 1 st transfer unit 315 sucks and holds the front surface 101 of the wafer 100, and transfers the wafer to the chuck table 310. The chuck table 310 suctions and holds the protective member 105 formed on the back surface 102 of the wafer 100 by the holding surface 311. As a result, the wafer 100 is held on the chuck table 310 with the front surface 101 exposed, as shown in fig. 7.

Then, the 2 nd control part 36 calculates the thickness of the wafer 100 at least 3 locations on the circumference centering on the center of the wafer 100 by the height meter 320.

The height gauge 320 makes the 1 st contact 321 and the 2 nd contact 322 contact the outer frame 312 and the front surface 101 of the wafer 100, respectively, which are coplanar with the holding surface 311 of the chuck table 310. Thus, the height gauge 320 can measure the height of the holding surface 311 of the chuck table 310 and the height of the wafer 100. The height gauge 320 can calculate the thickness of the wafer 100 from the difference between the measured height of the holding surface 311 and the height of the wafer 100.

As shown in fig. 7 and 6, the chuck table 310 includes, below it: a motor 317 as a rotation unit that rotates the chuck table 310; and an encoder 318 for detecting a rotation angle of the motor 317, that is, a rotation angle of the chuck table 310. The chuck table 310 is rotated by a motor 317 around a rotation axis 401 passing through the center of the holding surface 311 and the wafer 100.

In the thickness calculating step of the grinding apparatus 3, the 2 nd control unit 36 calculates the thickness of the wafer 100 by the height gauge 320 while rotating the chuck table 310 by the motor 317.

That is, as shown in fig. 8, the 2 nd control unit 36 rotates the chuck table 310 and causes the 2 nd contact 322 of the height gauge 320 to sequentially contact the 1 st calculated position 411, the 2 nd calculated position 412, and the 3 rd calculated position 413, which are at least 3 locations on the circumference 402 around the rotation axis 401, which is the center of the wafer 100. At this time, the 2 nd control unit 36 brings the 1 st contact 321 of the height gauge 320 into contact with the outer frame measurement position 410 on the outer frame 312 of the chuck table 310 located outside the respective calculation positions 411 to 413.

Thus, the 2 nd controller 36 calculates 3 thickness values of the wafer 100 at the 1 st calculation position 411, the 2 nd calculation position 412, and the 3 rd calculation position 413. Hereinafter, the thickness values of the wafer 100 at the 1 st, 2 nd and 3 rd calculated positions 411, 412 and 413 are referred to as the 1 st, 2 nd and 3 rd thickness values T1, T2 and T3, respectively.

[ calculating procedure ]

In this calculation step, the 2 nd controller 36 calculates the thickness difference Δ T, which is the difference between the reference value and the other 2 thickness values, using 1 of the 3 thickness values T1 to T3 calculated in the thickness calculation step as a reference value.

For example, the following thickness values are obtained in the thickness calculation step.

1 st thickness value T1 for 1 st calculated position 411: 850 μm

The 2 nd thickness value T2 for the 2 nd calculated position 412: 900 μm

3 rd thickness value T3 for the 3 rd calculated position 413: 900 μm

In this case, the 2 nd control unit 36 calculates 50 μm as the thickness difference Δ T, while taking, for example, the 1 st thickness value T1(850 μm) as a reference value.

After the calculation step, the 2 nd transfer unit 316 sucks and holds the front surface 101 of the wafer 100 on the holding surface 311 of the chuck table 310, and transfers the wafer 100 to the spin cleaning unit 350.

[ gradient adjustment Process ]

In this tilt adjustment step, the 1 st control unit 20 of the protective member forming apparatus 2 shown in fig. 2 adjusts 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, using the thickness difference Δ T calculated in the calculation step, before forming the protective member next.

For example, as shown in the above example, the 1 st thickness value T1 as the reference value is 850 μm, while the 2 nd and 3 rd thickness values T2 and T3 are 900 μm, and the thickness difference Δ T is 50 μm.

As shown in fig. 9, the distances from the rotation axis 401 to the 1 st calculation position 411, the 2 nd calculation position 412, and the 3 rd calculation position 413 shown in fig. 8, that is, the radius of the circumference 402 of the predetermined calculation positions 411 to 413 is 124.5 mm.

The 3 adjustment axes 255 in the holding unit 250 of the protective member forming apparatus 2 shown in fig. 2 are located at intervals of 120 degrees on a circumference centered on the central axis 501 passing through the center of the wafer holding surface 252 in the wafer holding portion 253 shown in fig. 10. The radius of the circumference, that is, the distance between the center axis 501 and the 3 adjustment axes 255 is 120 mm.

Further, as shown in fig. 11, the relationship between the 1 st calculation position 411, the 2 nd calculation position 412, and the 3 rd calculation position 413 as 3 calculation points and the outer diameters of the 3 adjustment axes 255 and the wafer 100 is set, and the calculation positions 411 to 413 are arranged so as to correspond to the 3 adjustment axes 255. In FIG. 11, a circle 502 defining 3 adjustment axes 255 is shown in addition to the outer diameter of the wafer 100 and the circle 402 defining the calculated positions 411 to 413.

In this case, since the radius of the circumference 402 is 124.5mm and the thickness difference Δ T is 50 μm, the 1 st control unit 20 of the protective member forming apparatus 2 determines that: the wafer holding surface 252 and the film holding surface 221 are deviated from being parallel to each other at an angle θ such that tan θ becomes 50 μm/124.5 mm.

Then, in order to adjust the offset, the 1 st control unit 20 uses 2 adjustment axes 255 corresponding to the 2 nd calculation position 412 and the 3 rd calculation position 413, and adjusts the interval between the support structure 251 and the wafer holding portion 253 at the portion where these adjustment axes 255 are provided, as shown in fig. 10, in accordance with the adjustment value Δ S.

In the above example, since the distance between the center axis 501 and the 3 adjustment axes 255 is 120mm, Δ S is 48.19 μm (120mm · tan θ). That is, the 1 st control unit 20 uses 2 adjustment shafts 255 corresponding to the 2 nd calculation position 412 and the 3 rd calculation position 413 to extend the distance Δ S between the support structure 251 and the wafer holding portion 253 at the installation position of these adjustment shafts 255. This can improve the parallelism between the film holding surface 221 of the stage 220 and the wafer holding surface 252 of the holding unit 250.

[ peeling Process ]

In this peeling step, the protective member 105 (see fig. 5 and the like) including the resin layer 104 and the film 103 is peeled from the wafer 100 using the peeling apparatus 4 shown in fig. 12.

As shown in fig. 12, the peeling apparatus 4 has a holding unit 42 for holding and carrying the wafer 100. The holding unit 42 has: a holding pad 421 for performing suction holding of the wafer 100; an arm portion 420 that supports the holding pad 421; a Z-axis direction moving unit 423 for supporting the arm 420 and reciprocating the arm 420 in the Z-axis direction; a movable plate 429 that supports the Z-axis direction moving means 423; and a Y-axis direction moving unit 422 for reciprocating the movable plate 429 in the Y-axis direction.

In the peeling apparatus 4, first, the holding pad 421 of the holding unit 42 is moved to the spin cleaning unit 350 of the grinding apparatus 3 shown in fig. 6 adjacent to the peeling apparatus 4 by the Y-axis direction moving unit 422 and the Z-axis direction moving unit 423. Then, the holding pad 421 performs suction holding on the front surface 101 of the wafer 100 placed on the spin cleaning unit 350.

Then, the holding unit 42 places the wafer 100 on the holding table 441 such that the front surface 101 faces upward. The holding stage 441 sucks and holds the wafer 100. Then, the holding table 441 and the outer-portion peeling unit 443 peel off only the outer portions of the protective members 105 of the wafer 100 shown in fig. 5 from the back surface 102 of the wafer 100 at a plurality of locations (for example, 7 locations). After the peeling, the suction of the wafer 100 by the holding table 441 is released.

Next, the holding unit 42 sucks the wafer 100 on the holding table 441 by the holding pad 421, and conveys and fixes the wafer 100 to a position above the entire peeling unit 43.

The entire peeling unit 43 includes a grip portion 431 and a moving member 432 that moves the grip portion 431 in the X-axis direction. The holding part 431 holds an outer part of the wafer 100, which is peeled off from the-X side of the protective member 105. In this state, the moving member 432 moves the grip 431 to the + X side. Since the position of the wafer 100 is fixed, the protective member 105 is peeled off from the back surface 102 of the wafer 100 by the movement of the grip portion 431 gripping the protective member 105. At this time, the guide roller 452 abuts against the lower surface of the protective member 105.

The peeled protective member 105 is temporarily placed on the temporary placement table 406. The staging table 406 has a plurality of plates 460 extending in the X-axis direction. The plurality of plates 460 are arranged at predetermined intervals in the Y-axis direction. Each plate 460 extends to be longer than the diameter of the wafer 100 and has a predetermined thickness in the Y-axis direction. The temporary placement table 406 has a larger placement area than the wafer 100 as a whole.

A protective member feeding unit 407 for feeding the protective member 105 placed on the temporary stage 406 to the cassette 479 is provided below the temporary stage 406. The protective member feeding unit 407 has an arm 470 extending in the Y-axis direction, and 2 pins 471 included in the arm 470. The pin 471 extends in such a manner as to protrude from the upper surface of the plate 460 of the staging platform 406.

When the arm 470 is moved in the X-axis direction by the motor-driven guide actuator 472, the pin 471 protruding from the plate 460 of the temporary placement table 406 is also moved in the X-axis direction. Thereby, the protective member 105 placed on the temporary stage 406 falls down into the cassette 479.

In the cassette 479, a pair of optical sensors 480 are provided at the upper end portions of one of the opposing sides. The optical sensor 480 includes a light emitting portion and a light receiving portion. The light receiving part of the optical sensor 480 receives the light generated from the light emitting part, and detects whether or not the protective member 105 collected in the cassette 479 is full, based on a change in the amount of light received by the light receiving part.

Then, in the peeling apparatus 4, the holding unit 42 transfers the wafer 100 to the grinding apparatus 3 shown in fig. 6, and is placed on the spin cleaning unit 350 with the front surface 101 facing upward. When the wafer 100 is placed on the spin cleaning unit 350, the 2 nd transfer robot 31 of the grinding apparatus 3 holds the wafer 100 and stores the wafer on the shelf 511 of the delivery cassette 51 through the 2 nd opening 513.

Further, the 2 nd transfer robot 31 may stand by above the spin cleaning unit 350, and the holding unit 42 of the peeling apparatus 4 may deliver the wafer 100 to the 2 nd transfer robot 31.

Next, the 1 st transfer robot 21 of the protective member forming apparatus 2 shown in fig. 2 takes out the wafer 100 from the shelf 511 of the delivery cassette 51 through the 1 st opening 512, and places the wafer on the 1 st support table 202 of the protective member forming apparatus 2. After that, the protective member forming step, the thickness calculating step, the inclination adjusting step, and the peeling step are repeated until, for example, the thickness difference Δ T calculated in the calculating step becomes equal to or less than a predetermined value.

As described above, in the present embodiment, the thickness of the wafer 100 including the protective member 105 is calculated at least 3 locations using the height gauge 320 of the grinding device 3, and the inclination 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 device 2, that is, the parallelism between the film holding surface 221 and the wafer holding surface 252 can be adjusted based on the thickness difference, which is the difference in thickness calculated at the 3 locations. Thus, when the protective member 105 is formed on the wafer 100 in the protective member forming apparatus 2, the thickness unevenness of the wafer 100 including the protective member 105 can be suppressed.

In the present embodiment, the protective member forming step, the thickness calculating step, the inclination adjusting step, and the peeling step can be performed without intervening in the operation of the operator. This enables the adjustment of the inclination relationship between the film holding surface 221 and the wafer holding surface 252 in the protective member forming apparatus 2 to be automated. Therefore, the thickness unevenness of the wafer 100 including the protective member 105 can be more easily suppressed.

In the present embodiment, the wafer 100 from which the protective member 105 has been peeled in the peeling step is returned to the protective member forming apparatus 2 again, and the protective member forming step, the thickness calculating step, the inclination adjusting step, and the peeling step are repeated. This can improve the accuracy of adjusting the inclination relationship between the film holding surface 221 and the wafer holding surface 252. In addition, since one wafer 100 is repeatedly used, the cost for adjustment can be reduced.

In the present embodiment, the protective member forming step, the thickness calculating step, the inclination adjusting step, and the peeling step are repeatedly performed. However, these steps may be performed 1 time each without being repeated. In this case, the parallelism between film holding surface 221 of stage 220 and wafer holding surface 252 of holding unit 250 can be improved to some extent.

In the present embodiment, the peeling step is performed after the tilt adjustment step. Instead, the peeling step may be performed after the thickness calculation step and before the tilt adjustment step, or may be performed simultaneously with the tilt adjustment step.

Further, the peeling step may not be performed. In this case, the wafer manufacturing apparatus 1 may not include the peeling apparatus 4. That is, in the method for adjusting the thickness of the protective member according to the present embodiment, at least the protective member forming apparatus 2 and the grinding apparatus 3 shown in fig. 1 may be used. In this case, too, the parallelism between film holding surface 221 of stage 220 and wafer holding surface 252 of holding unit 250 can be improved.

In the present embodiment, the thickness calculation site in the thickness calculation step is set to 3 sites, that is, the 1 st calculation position 411, the 2 nd calculation position 412, and the 3 rd calculation position. In this regard, the thickness calculation portion in the thickness calculation step may be at least 3 portions, or may be 4 or more portions.