Bearing device for grinding apparatus, grinding apparatus, grinding method, and silicon wafer

Abstract

Provided in the embodiments of the present disclosure are a bearing device for a grinding apparatus, a grinding apparatus, a grinding method, and a silicon wafer. The bearing device is used for supporting a silicon wafer in a horizontal direction, such that a first surface of the silicon wafer is ground from above. The bearing device comprises: a housing; and a soft portion at least partially surrounded by the housing, the soft portion being configured to be in contact with a second surface of the silicon wafer via an upper surface thereof, so as to deform on the basis of the shape of the second surface when the silicon wafer is ground, the first surface being opposite to the second surface.

Description

Supporting devices for grinding equipment, grinding equipment, grinding methods, and silicon wafers.

[0001] Cross-reference to related applications

[0002] This disclosure claims priority to Chinese Patent Application No. 202411716191.1, filed in China on November 27, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of silicon wafer processing technology, and more particularly to a support device for a grinding equipment, a grinding equipment, a grinding method, and a silicon wafer. Background Technology

[0004] As the carrier of semiconductor circuit manufacturing processes, the quality of silicon wafers has a decisive impact on the formation of integrated circuits. Currently, the main processes in silicon wafer processing include: physical grinding, chemical grinding, chemical etching, physical polishing, and chemical polishing of silicon wafers cut from single-crystal silicon rods.

[0005] During production and processing, factors such as internal stress, thermal stress, or other external forces can cause deformation of silicon wafers, resulting in poor wafer morphology. For example, silicon wafers may have excessive bow and warp, which are parameters used to describe the bending and warping of silicon wafers. Silicon wafers with excessive bow and warp are not only more prone to cracking or damage during processing and use, but also affect the performance and yield of the final device.

[0006] In actual production and processing, it is desirable to eliminate or reduce bending and warping of silicon wafers that may have occurred in previous processes such as wire cutting through the grinding process. In the horizontal grinding process, the silicon wafer needs to be placed horizontally on the worktable so that the grinding head can uniformly thin it.

[0007] However, if the silicon wafer has significant bending and warping before entering the polishing process, resulting in an uneven surface, only a portion of the supported surface will contact the worktable when the wafer is placed on a flat surface, while the other portion will be suspended in the air. In this situation, polishing cannot be performed while the silicon wafer is stably held. Furthermore, polishing not only fails to correct the bending and warping of the wafer but also causes increased bending and warping, uneven thickness, decreased surface quality, and damage to the internal structure, among other problems. Summary of the Invention

[0008] In view of this, embodiments of the present disclosure aim to provide a support device, a polishing apparatus, a polishing method, and a silicon wafer for a polishing device. The support device is configured to effectively adapt to the surfaces of silicon wafers with different curvatures and warpages, providing uniform support for different silicon wafers during the polishing process, effectively avoiding damage caused by stress concentration, and ensuring that the amount of polishing applied to different areas of the silicon wafer meets expectations, thereby obtaining silicon wafers with reduced curvature and warpage, improved thickness uniformity, and enhanced surface quality.

[0009] The technical solution of this disclosure embodiment is implemented as follows:

[0010] In a first aspect, embodiments of this disclosure provide a support device for a grinding apparatus, the support device being used to support a silicon wafer in a horizontal direction so that a first surface of the silicon wafer is ground from above, wherein the support device includes:

[0011] case;

[0012] A soft portion at least partially surrounded by the housing, the soft portion being configured to contact a second surface of the silicon wafer via its upper surface to deform according to the shape of the second surface when the silicon wafer is polished, wherein the first surface is opposite to the second surface.

[0013] In some optional examples, the soft portion includes an insulating layer and a filling layer, wherein,

[0014] The upper surface of the isolation layer is in contact with the second surface of the silicon wafer, and the isolation layer and the housing enclose a sealed cavity.

[0015] The sealed chamber is filled with a soft material to form the filling layer.

[0016] In some optional examples, the carrier device further includes a supply section for supplying fluid to the upper surface of the isolation layer, and a discharge section for discharging the fluid away from the carrier device.

[0017] In some alternative examples, the supply section includes a first injection port formed on the housing, and the discharge section includes a first discharge port formed on the housing.

[0018] In some optional examples, the isolation layer is formed as a soft membrane.

[0019] In some alternative examples, the soft material is a fluid.

[0020] In some alternative examples, the housing is formed with a second inlet for injecting the fluid into the sealed chamber and a second outlet for discharging the fluid from the sealed chamber.

[0021] In some alternative examples, the support device is provided with a connection configured to transmit power to the support device to cause the support device to rotate in the horizontal direction.

[0022] Secondly, embodiments of this disclosure provide a grinding apparatus, the grinding apparatus comprising:

[0023] According to the first aspect, a support device for grinding equipment;

[0024] A grinding head configured to grind a first surface of a silicon wafer supported by the carrier from above.

[0025] In some optional examples, the grinding apparatus further includes a worktable on which the support device is disposed, the worktable being configured to drive the support device to rotate in the horizontal direction.

[0026] In some alternative examples, the worktable is provided with a drive unit configured to connect to the connection portion of the support device to drive the support device to rotate in the horizontal direction.

[0027] Thirdly, embodiments of this disclosure provide a grinding method, which is performed by a grinding apparatus according to the second aspect, the grinding method comprising:

[0028] The silicon wafer is supported horizontally by the bearing device of the grinding equipment;

[0029] The first surface of the silicon wafer is ground from above using the grinding head of the grinding equipment;

[0030] The method of supporting the silicon wafer in the horizontal direction by the bearing device of the grinding equipment includes: bringing the second surface of the silicon wafer, which is opposite to the first surface, into contact with the upper surface of the soft part of the bearing device, so that the soft part can deform according to the shape of the second surface when the silicon wafer is being ground.

[0031] Fourthly, embodiments of this disclosure provide a silicon wafer manufactured using a grinding method according to the third aspect, wherein the curvature and warpage of the silicon wafer are each less than 20 micrometers, and the total thickness deviation of the silicon wafer is less than 1.5 micrometers.

[0032] Embodiments of this disclosure provide a support device, a grinding apparatus, a grinding method, and a silicon wafer for a grinding machine. The support device is used to support the silicon wafer horizontally so that a first surface of the silicon wafer is ground from above. The support device is provided with a housing and a soft portion at least partially surrounded by the housing. This soft portion is configured to deform according to the actual shape of the second surface of the silicon wafer when in contact with and under pressure from the silicon wafer, thereby maximizing the contact area with the second surface. Thus, by compensating for the unevenness of the silicon wafer through the deformability of the soft portion, a more comprehensive, uniform, and stable support of the silicon wafer by the support device can be ensured during the grinding process, improving the stability of the grinding operation. This results in significant improvements in the curvature and warp, total thickness variation, and surface quality of the ground silicon wafer, and reduces the aggravated deformation and internal damage to the silicon wafer caused by uneven pressure distribution during the grinding process. Attached Figure Description

[0033] Figure 1 is a schematic diagram of conventional grinding equipment;

[0034] Figure 2 is a schematic diagram of the grinding equipment provided in an embodiment of this disclosure;

[0035] Figure 3 is a top view of a part of the grinding equipment in Figure 2;

[0036] Figure 4 is a schematic diagram of the support device provided in an embodiment of this disclosure;

[0037] Figure 5 is a schematic diagram of a support device provided in another embodiment of this disclosure;

[0038] Figure 6 is a schematic diagram of a support device provided in another embodiment of this disclosure;

[0039] Figure 7 is a schematic diagram of a support device provided in another embodiment of the present disclosure;

[0040] Figure 8 is a schematic diagram of a grinding apparatus provided in another embodiment of the present disclosure;

[0041] Figure 9 is a flowchart of the grinding method provided in an embodiment of this disclosure. Detailed Implementation

[0042] The technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0043] Referring to Figure 1, a schematic diagram of a conventional polishing apparatus is shown. This polishing apparatus 1 mainly includes a worktable 11 and a polishing head 12. The worktable 11 is used to ensure that the silicon wafer W is stably held during the polishing process. The polishing head 12 is used to polish the surface of the silicon wafer W held on the worktable 11.

[0044] The worktable 11 may have a horizontal bearing surface 111 for bearing the silicon wafer W in the horizontal direction. The worktable 11 may, for example, hold the silicon wafer W by vacuum adsorption during the grinding process to prevent the silicon wafer from shifting under the action of the grinding head 12.

[0045] The grinding head 12 may include a grinding section 121, a pressure section 122, and a driving section 123. The grinding section 121 can be used to directly grind the surface of a material. The pressure section 122 can be used to apply pressure to the silicon wafer W through the grinding section 121. The driving section 123 can be used to drive the grinding head 12 to move vertically and rotate about its own axis of rotation.

[0046] When grinding a silicon wafer using grinding equipment 1, the first surface of the silicon wafer can be ground first using grinding head 12. During this process, the silicon wafer contacts the bearing surface 111 of the worktable 11 through the second surface opposite to the first surface, so that it is supported by the worktable 111. After this grinding operation is completed, the silicon wafer can be flipped over, and the second surface of the silicon wafer can be ground while the silicon wafer is supported by the worktable through the first surface. Alternatively, the grinding order can be changed, that is, the first surface can be ground after the second surface. It should be noted that in the various embodiments of this disclosure, the surface of the silicon wafer refers to: the surface of the silicon wafer used to form a semiconductor device and the surface opposite to that surface. In the art, these two surfaces can also be referred to as the front and back surfaces of the silicon wafer, respectively.

[0047] In this field, it is desirable to eliminate or reduce morphological defects in silicon wafers caused by previous processes through polishing operations, such as reducing wafer curvature and warpage, improving wafer thickness uniformity, and enhancing surface quality. However, in actual production, the morphology of polished silicon wafers often still fails to meet requirements.

[0048] To address the aforementioned problems, the inventors discovered that in existing grinding equipment 1, the bearing surface 111 of the worktable 11 is flat. However, the silicon wafer to be processed is non-flat due to morphological defects, especially having two non-flat surfaces. When the non-flat silicon wafer is placed on the flat bearing surface 111 of the worktable 11, the bearing surface of the silicon wafer only partially contacts the bearing surface 111. In fact, only the high points on this surface of the silicon wafer can contact the bearing surface 111 and form support points, while the low point areas are suspended or have poor contact with the bearing surface 111, as shown in Figure 1.

[0049] Further research revealed that the inventors noticed the aforementioned issues could lead to numerous problems in subsequent silicon wafer processing. Specifically, during the grinding process, uneven contact between the silicon wafer and the worktable's supporting surface could cause the wafer to wobble upon contact with the grinding head, resulting in unstable grinding operations. Furthermore, it could cause excessive pressure on high-point areas and insufficient pressure on low-point areas. This localized excessive pressure could create stress concentration in these areas, leading to structural damage to the silicon wafer, such as lattice deformation. When the stress exceeds the intrinsic strength of the silicon wafer material, cracks might form in the pressure concentration areas. In severe cases, these cracks could propagate to other parts of the silicon wafer, particularly edges or weak areas with existing micro-defects, causing localized wafer breakage. Additionally, when a bent or warped silicon wafer flattens under the pressure of the grinding head, it might push low-point areas that were previously out of contact with the grinding head towards it, subjecting these areas to excessive grinding. Moreover, the unstable support of the silicon wafer directly contributes to the instability of the grinding operation, making the specific grinding position of the grinding head on the silicon wafer surface uncertain. These factors result in uneven overall thickness and poor surface quality of the milled silicon wafer, and may even introduce new or exacerbate existing bends and warps, such as introducing new bends and warps in the edge areas of the silicon wafer.

[0050] In view of the above, embodiments of this disclosure aim to provide a support device, a polishing apparatus, a polishing method, and a silicon wafer for a polishing device. The support device is configured to effectively adapt to the surfaces of silicon wafers with different curvatures and warpages, providing comprehensive and uniform support for different silicon wafers during the polishing process. This improves the stability of the polishing operation and ensures that the amount of polishing applied to different areas of the silicon wafer meets expectations. The result is a silicon wafer with reduced curvature and warpage, uniform thickness, and improved surface quality, while effectively preventing silicon wafer damage caused by stress concentration.

[0051] The embodiments of this disclosure are described in detail below with reference to the accompanying drawings.

[0052] Referring to Figure 2, some embodiments of this disclosure provide a support device 13 for a grinding apparatus. The support device 13 is used to support a silicon wafer W in a horizontal direction so that the first surface S1 of the silicon wafer W can be ground from above.

[0053] The support device 13 may include a housing 131 and a soft portion 132 at least partially surrounded by the housing 131. The soft portion 132 may be configured to contact the second surface S2 of the silicon wafer W through its upper surface, so as to deform according to the shape of the second surface S2 when the silicon wafer W is polished, wherein the first surface S1 is opposite to the second surface S2.

[0054] Specifically, the carrier device 13 can be configured to hold the silicon wafer W in a generally horizontal direction and expose the first surface S1 or the second surface S2 above it so as to grind the exposed first surface S1 or the second surface S2 from above without interfering with the grinding operation.

[0055] In some embodiments of this disclosure, as shown in Figures 2 and 3, the housing 131 of the support device 13 can be configured as generally annular to restrict the silicon wafer W from its outer periphery, thereby preventing the silicon wafer W from displacing horizontally relative to the support device 13. The housing 131 can be made of materials such as metal or rigid plastic. To prevent the silicon wafer W from rotating in the same direction as the grinding head during the grinding process, thus affecting the grinding efficiency, as shown in Figure 3, the support device 13 can also be provided with an anti-rotation part 133. The anti-rotation part 133 can be configured to engage with a notch on the silicon wafer W, thereby preventing the silicon wafer W from rotating about its center relative to the support device 13. It should be noted that the support device 13 can also restrict the rotation of the silicon wafer W relative to it in other ways, which are not limited here.

[0056] With the housing 131 formed in a generally annular shape, the housing 131 can be disposed around the soft portion 132 in the circumferential direction. The soft portion 132 may or may not be connected to the worktable 11, and this disclosure does not limit this. The soft portion 132 may be made of a soft material, such as rubber, silicone, or other materials with deformability and shape memory properties, to allow the soft portion 132 to deform according to the surface of the silicon wafer it contacts during silicon wafer grinding. The support device 13 can contact one surface of the silicon wafer W via the soft portion 132, so the surface of the soft portion 132 for contacting the silicon wafer W can have a shape corresponding to the first surface S1 or the second surface S2 of the silicon wafer W. To ensure full support of the silicon wafer W by the soft portion 132, the surface of the soft portion 132 for contacting the silicon wafer W has an area larger than the first surface S1 or the second surface S2 of the silicon wafer W.

[0057] As shown in Figure 2, a silicon wafer W can be placed on the flexible portion 132 in a generally horizontal direction, such that the flexible portion 132 contacts the second surface S2 of the silicon wafer W. Once the silicon wafer W is placed on the flexible portion 132, the flexible portion 132 can deform under the gravity of the silicon wafer W. This deformation increases the contact area between the flexible portion 132 and the second surface S2 of the silicon wafer W. In this case, the flexible portion 132 not only contacts the high points on the second surface S2 of the silicon wafer W, but can also contact other areas on the second surface S2, even the low-lying areas.

[0058] During the grinding process, the grinding head applies pressure to the first surface S1 of the silicon wafer W while grinding it. The pressure on the silicon wafer W can be directly transmitted to the soft part 132. Under the combined action of the pressure and the weight of the silicon wafer W itself, the soft part 132 is further deformed, thereby further increasing the contact area between the silicon wafer W and the soft part 132.

[0059] The material and dimensions of the flexible portion 132 can be determined based on the specifications of the silicon wafer and grinding process parameters, such as the pressure applied by the grinding head to the silicon wafer during grinding. The flexible portion 132 can be designed to not only increase the contact area with the silicon wafer by deforming according to pressure and the shape of the silicon wafer, especially filling low-point areas, but also to maintain sufficient rigidity after deformation to provide necessary support for the silicon wafer. In other words, it can withstand continuous grinding operations without complete deformation in terms of mechanical properties, thereby ensuring the flatness and stability of the silicon wafer during the grinding process.

[0060] With the deformed soft portion 132 providing comprehensive and uniform support to the second surface S2 of the silicon wafer W, the grinding head can remove material from the first surface S1 of the silicon wafer W in a top-to-bottom sequence, gradually flattening the uneven first surface S1 until the grinding amount on the first surface S1 reaches a preset value. This grinding amount can be set according to the final product thickness requirements and the morphology of the silicon wafer before grinding. Because the soft portion 132 maintains stable support for the silicon wafer W throughout this process, and the housing 131 restricts the silicon wafer W, the silicon wafer W essentially does not deform or shift. This avoids damage to the silicon wafer due to stress concentration, ensuring that the amount of material removed by the grinding head in each area is as expected, preventing under-grinding of high-point areas or over-grinding of low-point areas. Consequently, the curvature and warpage of the ground silicon wafer are reduced, and the overall thickness is more uniform. Furthermore, performing the grinding operation under these stable conditions ensures that the surface of the silicon wafer is uniformly ground, thus resulting in improved surface quality. Embodiments of this disclosure provide a support device 13 for a grinding apparatus. The support device 13 is used to support the silicon wafer W in a horizontal direction so that the first surface of the silicon wafer W can be ground from above. The support device 13 is provided with a housing 131 and a soft part 132 at least partially surrounded by the housing 131. The soft part 132 is configured to deform according to the actual shape of the second surface S2 of the silicon wafer W when it comes into contact with and is subjected to pressure from the silicon wafer W, so as to maximize the contact area with the second surface S2. Thus, by compensating for the unevenness of the silicon wafer W through the deformability of the soft part 132, it is ensured that the support device 13 provides more comprehensive, uniform and stable support for the silicon wafer W during the grinding process, thereby improving the stability of the grinding operation. This results in significant improvements in the curvature and warp, total thickness variation and surface quality of the ground silicon wafer W, and reduces the aggravated deformation and internal damage of the silicon wafer caused by uneven pressure distribution during the grinding process.

[0061] Besides using a single material, the soft portion 132 can also be a composite structure made of multiple materials. In some embodiments of this disclosure, referring to FIG4, the soft portion 132 may include an isolation layer 132a and a filling layer 132b, wherein the upper surface of the isolation layer 132a is in contact with the second surface S2 of the silicon wafer W, and the isolation layer 132a and the housing 131 enclose a sealed cavity 131a, the sealed cavity 131a being filled with a soft material to form the filling layer 132b.

[0062] Unlike the embodiments shown in Figures 2 and 3, in the embodiment shown in Figure 4, the housing 131 includes a bottom and a circumferential portion extending around the outer peripheral edge of the bottom, i.e., additionally having a bottom compared to the annulus in Figures 2 and 3.

[0063] The isolation layer 132a can be sealed to the inner wall of the circumferential portion of the housing 131, and the bottom and circumferential portion of the housing 131 can be integrally formed, thereby defining a sealed chamber 131a together with the circumferential portion and the bottom of the housing 131. In other embodiments of this disclosure, the bottom and circumferential portion of the housing 131 can be formed separately and sealed together. This disclosure does not limit this aspect.

[0064] The isolation layer 132a, as part of the soft portion, is used for direct contact with the second surface S2 of the silicon wafer. Therefore, the isolation layer 132a can possess good deformability to adapt to the irregularities of the second surface S2. In some embodiments of this disclosure, the isolation layer 132a is formed as a soft film.

[0065] To achieve the above functions, the material of the isolation layer can be selected to be a material with compressibility and resilience, such as rubber, silicone or polyurethane, so as to provide the necessary deformation during the silicon wafer grinding process.

[0066] The filler layer 132b may be made of a soft material to provide support and ensure that the silicon wafer is subjected to uniform pressure during the polishing process. In some embodiments of this disclosure, the soft material may be a fluid.

[0067] Specifically, the soft material of the filling layer can be a liquid such as deionized water, hydraulic oil, or silicone oil, or a gas such as air, nitrogen, or argon. Liquid filling materials can provide better pressure control and uniformity, while gas filling materials are easier to control and maintain.

[0068] The inventors also discovered through research that silicon wafers may still have impurities adhering to their surfaces before polishing. These impurities include, for example, residual cutting fluid after wire cutting, and environmental impurities that adhere to the wafer surface during transport from the wire cutting station to the polishing station. Furthermore, during polishing, the removed silicon wafer portions may also scatter into the surrounding environment as particles, eventually adhering at least partially to the supported surface of the wafer. If these impurities or particles are not cleaned, they may damage the supported surface of the wafer during the polishing process through the supporting force of the soft portions.

[0069] In order to clean the silicon wafer in a timely manner, in some embodiments of this disclosure, the carrier device 13 may further include: a supply section 131b for providing fluid to the upper surface of the isolation layer, and a discharge section 131c for discharging the fluid away from the carrier device.

[0070] The supply section 131b and the discharge section 131c can be configured to be in fluid communication with the space formed by the circumferential portion of the housing 131 of the carrier device 13 and the upper surface of the isolation layer 132a, respectively. The fluid supplied by the supply section 131b can clean the second surface S2 of the silicon wafer and the upper surface of the isolation layer 132a, and the contaminated fluid after cleaning can be discharged away from the carrier device 13 in a timely manner through the discharge section 131c to avoid secondary contamination. The supply section 131b and the discharge section 131c can be used during the polishing operation, or before or after the polishing operation, to clean the carrier device 13 in advance or at the end.

[0071] In some embodiments of this disclosure, referring to FIG5, the supply section 131b may include a first injection port 131d formed on the housing 131, and the discharge section 131c may include a first discharge port 131e formed on the housing 131.

[0072] The first inlet 131d and the first outlet 131e can be disposed on the circumferential portion of the housing 131 and open towards the inside of the housing 131. The first inlet 131d and the first outlet 131e are located above the isolation layer 132a in the vertical direction. Multiple first inlets and multiple first outlets can be provided, and the first inlets and first outlets can be arranged opposite each other to form a fluid flow path from the first inlet through the isolation layer 132a to the first outlet. In some embodiments of this disclosure, the first inlet 131d and the first outlet 131e are disposed close to the upper surface of the isolation layer 132a to increase the fluid flow rate and thus improve cleaning efficiency.

[0073] The selection, density, and volume ratio of the soft material to the sealed chamber 131a can be determined based on the grinding process parameters, the morphology of the silicon wafer before grinding, and the performance requirements after grinding, and can vary for different application scenarios. To more accurately match application scenarios and improve the versatility of the support device 13, in some embodiments of this disclosure, referring to FIG6, when the soft material is a fluid, the housing 131 has a second inlet 131f for injecting fluid into the sealed chamber 131a and a second outlet 131g for discharging fluid from the sealed chamber 131a.

[0074] The second inlet 131f and the second outlet 131g can be disposed on the circumferential portion of the housing 131 and open toward the inside of the housing 131. The second inlet 131f and the second outlet 131g are located below the isolation layer 132a in the vertical direction. A plurality of second inlets and a plurality of second outlets can be provided, and the second inlets and the second outlets can be arranged opposite each other to form a fluid flow path from the second inlet through the sealed chamber to the second outlet.

[0075] By adjusting the amount of fluid filling the sealed chamber through the second injection port 131f and the second discharge port 131g, the deformation capability of the entire soft part can be changed to accommodate silicon wafers of different morphologies and provide appropriate support for different grinding parameters.

[0076] To improve grinding efficiency and uniformity, the support device 13 can be rotated during the grinding process to drive the silicon wafer W to rotate. In some embodiments of this disclosure, referring to FIG7, the support device 13 may be provided with a connecting part 131h, which may be configured to transmit power to the support device 13 so that the support device 13 rotates in the horizontal direction.

[0077] In the embodiment shown in Figure 7, the connecting portion 131h is formed as a through hole in the housing 131. It is understood that this is only one implementation of the connecting portion. In other embodiments not shown, the connecting portion 131h can be implemented in other forms, as long as it can be driven into contact with a power supply device.

[0078] Referring to Figure 2, some embodiments of this disclosure also provide a polishing apparatus 1. The polishing apparatus 1 may include: a support device 13 for polishing apparatus as described above; and a polishing head 12 configured to polish a first surface S1 of a silicon wafer S supported by the support device 13 from above.

[0079] In order to achieve the rotation of the silicon wafer during the grinding process, in some other embodiments of this disclosure, referring to FIG8, the grinding equipment 1 may further include a worktable 11, and a support device 13 may be disposed on the worktable 11. The worktable 11 may be configured to drive the support device 13 to rotate in the horizontal direction, so as to drive the silicon wafer to rotate in the horizontal direction. The rotation direction of the silicon wafer and the rotation direction of the grinding head may be opposite, and their rotation speeds may be the same or different. This disclosure does not limit this.

[0080] In order to enable the workbench 11 to drive the support device 13, in some other embodiments of this disclosure, referring to FIG8, the workbench 11 may be provided with a drive unit 112, which is configured to be connected to the connection part 131h of the support device 13 to drive the support device 13 to rotate in the horizontal direction.

[0081] As shown in Figure 8, the drive unit 112 includes a base 112a and a drive member 112b fixedly connected to the base. The base 112a can be connected to a power source, such as an electric motor (not shown), to rotate under the drive of the power source. The drive member 112b can be connected to the connecting portion 131h of the support device 13 to transmit the power provided by the power source to the support device 13. In the embodiment shown in the figure, the drive member 112b is formed as a pin, and the connecting portion 131h is formed as a hole; the two can be in a clearance or transition fit. The drive unit 112 can also be formed in other forms, and correspondingly, the connecting portion 131h of the support device 13 can also be formed in other forms, as long as it can transmit power to realize the rotation of the support device 13; this disclosure does not limit this.

[0082] This disclosure also provides a grinding method, as shown in FIG9, which is performed by the grinding apparatus 1 described above, and includes:

[0083] S01. The silicon wafer W is supported horizontally by the bearing device 13 of the grinding equipment 1;

[0084] S02. The first surface S1 of the silicon wafer W is ground from above by the grinding head 12 of the grinding equipment 1;

[0085] The method of supporting the silicon wafer W in the horizontal direction by the bearing device 13 of the grinding equipment 1 includes: making the second surface S2 of the silicon wafer W, which is opposite to the first surface S1, contact the upper surface of the soft part 132 of the bearing device 13, so that the soft part 132 can deform according to the shape of the second surface S2 when the silicon wafer W is being ground.

[0086] In some embodiments of this disclosure, a silicon wafer can be obtained by using the polishing method provided in the embodiments of this disclosure, wherein the silicon wafer has a curvature and warp of less than 20 micrometers, a total thickness variation (TTV) of less than 1.5 micrometers, and the silicon wafer surface is free of pits or protrusions caused by polishing. The changes in curvature, warp, and TTV values ​​of the silicon wafer before polishing and after polishing using the polishing method provided in the embodiments of this disclosure are shown in Table 1.

[0087] Table 1

[0088] It should be noted that the technical solutions described in the embodiments of this disclosure can be combined arbitrarily without conflict.

[0089] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A support device for a grinding apparatus, the support device being used to support a silicon wafer in a horizontal direction so that a first surface of the silicon wafer is ground from above, wherein, The supporting device includes: case; A soft portion at least partially surrounded by the housing, the soft portion being configured to contact a second surface of the silicon wafer via its upper surface to deform according to the shape of the second surface when the silicon wafer is polished, wherein the first surface is opposite to the second surface.

2. The support device for grinding equipment according to claim 1, wherein, The soft portion includes an insulating layer and a filling layer, wherein, The upper surface of the isolation layer is in contact with the second surface of the silicon wafer, and the isolation layer and the housing enclose a sealed cavity. The sealed chamber is filled with a soft material to form the filling layer.

3. The support device for grinding equipment according to claim 2, wherein, The support device further includes: a supply section for supplying fluid to the upper surface of the isolation layer, and a discharge section for discharging the fluid away from the support device.

4. The support device for grinding equipment according to claim 3, wherein, The supply section includes a first injection port formed on the housing, and the discharge section includes a first discharge port formed on the housing.

5. The support device for a grinding equipment according to claim 2, wherein, The isolation layer is formed as a soft membrane.

6. The support device for a grinding apparatus according to any one of claims 2 to 5, wherein, The soft material is a fluid.

7. The support device for a grinding equipment according to claim 6, wherein, The housing has a second inlet for injecting the fluid into the sealed chamber and a second outlet for discharging the fluid from the sealed chamber.

8. The support device for a grinding apparatus according to any one of claims 1 to 5, wherein, The bearing device is provided with a connecting part, which is configured to transmit power to the bearing device so that the bearing device can rotate in the horizontal direction.

9. A grinding apparatus, the grinding apparatus comprising: The support device for grinding equipment according to any one of claims 1 to 8; A grinding head configured to grind a first surface of a silicon wafer supported by the carrier from above.

10. The grinding apparatus according to claim 9, wherein, The grinding equipment also includes a worktable, and the support device is disposed on the worktable. The worktable is configured to drive the support device to rotate in the horizontal direction.

11. The grinding apparatus according to claim 10, wherein, The worktable is provided with a drive unit, which is configured to be connected to the connection part of the support device to drive the support device to rotate in the horizontal direction.

12. A grinding method, said grinding method being performed by a grinding apparatus according to any one of claims 9 to 11, said grinding method comprising: The silicon wafer is supported horizontally by the bearing device of the grinding equipment; The first surface of the silicon wafer is ground from above using the grinding head of the grinding equipment; The method of supporting the silicon wafer in the horizontal direction by the bearing device of the grinding equipment includes: bringing the second surface of the silicon wafer, which is opposite to the first surface, into contact with the upper surface of the soft part of the bearing device, so that the soft part can deform according to the shape of the second surface when the silicon wafer is being ground.

13. A silicon wafer manufactured using the polishing method according to claim 12, wherein, The curvature and warpage of the silicon wafer are both less than 20 micrometers, and the total thickness deviation of the silicon wafer is less than 1.5 micrometers.

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