Wafer polishing method and wafer polishing apparatus

Abstract

The application provides a wafer grinding method and a wafer grinding device. The wafer grinding method comprises the following steps: placing a wafer on the surface of a wafer carrier disc of a wafer grinding device; obtaining preset fine grinding parameters, wherein the fine grinding parameters comprise the rotating speed n1 of a grinding wheel of the wafer grinding device and the rotating speed n2 of the wafer carrier disc when fine grinding is performed on the wafer; and controlling the rotation of the grinding wheel and the wafer carrier disc based on the fine grinding parameters, so that the surface of the wafer is ground by the grinding component of the grinding wheel. When fine grinding is performed on the wafer, the rotating directions of the grinding wheel and the wafer carrier disc are the same, and the fine grinding parameters satisfy n2 / n1=0.1±0.025. The application improves the uniformity of the surface roughness distribution of the wafer after grinding, and can meet the processing needs of products with high roughness requirements.

Description

Technical Field

[0001] This application relates to the field of semiconductor fabrication technology, specifically to a wafer grinding method and wafer grinding equipment. Background Technology

[0002] Currently, conductive silicon carbide (SiC) substrates are limited by wafer fabrication processes, resulting in concentration spots on the back side of the substrate. For example... Figure 1 As shown, there is a concentration spot region 110 with color difference on the back side of the wafer substrate 100 (flat edge facing up). The presence of this concentration spot region 110 will affect the surface roughness uniformity after the wafer is polished. Specifically, after the substrate is polished and thinned, the local roughness corresponding to this concentration spot region is lower.

[0003] Wafer polishing primarily utilizes the In-Feed method, mostly employing a Z1+Z2 (coarse polishing + fine polishing) approach. Because some semiconductor products require a high surface roughness (Ra>10nm) on the back side (or C-side) of the silicon carbide substrate, the coarse and fine polishing stages use the same SD2000 grinding wheel. In the fine polishing stage, if the grinding wheel speed is 3000 rpm, such as... Figure 2 As shown, this results in an overall roughness that is too low, failing to meet product requirements. Therefore, during the fine grinding stage, the grinding wheel speed can be reduced to 2000 rpm to meet the roughness requirements. However, at this time, the roughness of local areas of the substrate is affected by concentration spots, such as... Figure 3 As shown, the low roughness in the concentration spot area can easily lead to other potential product risks such as easy peeling of the back gold and fluctuations in electrical parameters. Since the SiC substrate itself has stable chemical properties, it is difficult to improve the roughness distribution by wet etching after polishing.

[0004] Therefore, there is a need to provide a wafer grinding method to overcome the problem that the overall roughness uniformity is poor due to the excessively low local surface roughness after wafer grinding.

[0005] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0006] To address the problems in the prior art, the purpose of this application is to provide a wafer grinding method and wafer grinding equipment, which improves the roughness at the concentration spot location, resulting in higher uniformity of the overall wafer roughness after grinding, while ensuring a larger average roughness value, thus meeting the processing needs of products with high roughness requirements.

[0007] This application provides a wafer polishing method, including:

[0008] Place the wafer on the surface of the wafer carrier tray of the wafer grinding equipment;

[0009] Obtain preset fine grinding parameters, which include the rotational speed n1 of the grinding wheel of the wafer grinding equipment and the rotational speed n2 of the wafer carrier disk when fine grinding the wafer;

[0010] The grinding wheel and the wafer carrier disk are controlled to rotate based on the fine grinding parameters so as to grind the surface of the wafer through the grinding component of the grinding wheel. When the wafer is finely ground, the grinding wheel and the wafer carrier disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.025.

[0011] In some embodiments, when the wafer is finely ground, the rotational speed n1 of the grinding wheel is 2000 rpm ± 500 rpm.

[0012] In some embodiments, when the wafer is finely ground, the rotational speed n2 of the wafer carrier disk is 200 rpm ± 50 rpm.

[0013] In some embodiments, the rotational speed n1 of the grinding wheel is 2000 rpm, and the rotational speed n2 of the wafer carrier disk is 200 rpm.

[0014] In some embodiments, before obtaining the preset fine grinding parameters, the following steps are also included:

[0015] Obtain preset coarse grinding parameters, which include the rotational speed of the grinding wheel and the rotational speed of the wafer support disk when coarse grinding the wafer;

[0016] The grinding wheel and the wafer carrier disk are rotated based on the coarse grinding parameters so as to grind the surface of the wafer through the grinding component of the grinding wheel.

[0017] In some embodiments, during the rough grinding of the wafer, the grinding wheel and the wafer support disk rotate in the same direction, and the rotational speed of the grinding wheel is greater than n1.

[0018] In some embodiments, when coarsely grinding the wafer, the rotational speed of the grinding wheel is 3000 rpm ± 500 rpm.

[0019] In some embodiments, the wafer grinding method is used to grind a wafer on a silicon carbide substrate.

[0020] A second aspect of this application also provides a wafer grinding apparatus, comprising:

[0021] Wafer carrier disk, used to hold wafers;

[0022] The grinding wheel includes multiple grinding components, which are disposed on the side of the grinding wheel facing the wafer carrier disk and are used to grind the wafer on the wafer carrier disk;

[0023] The first drive mechanism and the second drive mechanism drive the grinding wheel and the wafer carrier disk to rotate based on preset fine grinding parameters, so as to grind the surface of the wafer through the grinding component of the grinding wheel. The fine grinding parameters include the rotational speed n1 of the grinding wheel and the rotational speed n2 of the carrier disk when fine grinding the wafer.

[0024] During the fine grinding of the wafer, the grinding wheel and the wafer support disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.025.

[0025] In some embodiments, when the wafer is finely ground, the rotational speed n1 of the grinding wheel is 2000 rpm ± 500 rpm.

[0026] In some embodiments, when the wafer is finely ground, the rotational speed n2 of the wafer carrier disk is 200 rpm ± 50 rpm.

[0027] The wafer grinding method and wafer grinding equipment provided in this application have the following advantages:

[0028] This application improves the roughness of the concentration spot area by designing the relationship between the rotational speed of the grinding wheel and the rotational speed of the wafer carrier disk in the wafer grinding equipment. This results in higher roughness uniformity of the entire wafer after grinding, while ensuring a larger average roughness value, which can meet the processing needs of products with high roughness requirements. The wafer grinding method and equipment of this application can effectively overcome the influence of the concentration spot region on roughness uniformity when used for grinding wafers on silicon carbide substrates, achieving excellent grinding results. However, this application is not limited to this; the method and equipment can also be used to grind other types of wafers. Attached Figure Description

[0029] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0030] Figure 1 This is a top view of an existing wafer substrate with a concentration spot region facing the back side upwards.

[0031] Figure 2 and Figure 3This is a schematic diagram of the surface roughness distribution of a wafer when using different grinding wheel speeds;

[0032] Figure 4 This is a schematic diagram of a wafer grinding equipment;

[0033] Figure 5 This is a top view of a wafer grinding equipment;

[0034] Figure 6 This is a flowchart of a wafer polishing method according to an embodiment of this application;

[0035] Figure 7 and Figure 8 This is a schematic diagram of the surface roughness distribution of a wafer when different wafer carrier disk rotation speeds are used.

[0036] Figure label:

[0037] 100 wafer substrate

[0038] 110 concentration spot area

[0039] 10 Grinding wheels

[0040] 11 Grinding components

[0041] 20 wafer carrier disks

[0042] 30 wafers Detailed Implementation

[0043] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted. The words “or” and “or” in the specification may mean “and” or “or”. Although the terms “upper,” “lower,” etc., may be used in this specification to describe different exemplary features and elements of this application, these terms are used herein only for convenience, such as the orientation according to the examples described in the accompanying drawings. Nothing in this specification should be construed as requiring a specific three-dimensional orientation of the structure to fall within the scope of this application. Although “first” or “second,” etc., are used in this specification to denote certain features, they are only for indication of function and not as a limitation on the number or importance of specific features.

[0044] After fine grinding of silicon carbide substrate wafers, the uniformity of surface roughness distribution is affected by concentration spot regions, thus impacting the quality of semiconductor products fabricated using such wafers. Existing technologies generally assume that only the center and edges of the roughness distribution differ after grinding, neglecting the uneven roughness distribution caused by concentration spot regions. This application is the first to discover the influence of concentration spot regions on the roughness distribution of the grinding process and proposes a novel wafer grinding method and equipment solution. This improves the roughness at the concentration spot locations, resulting in higher overall wafer roughness uniformity after grinding, while ensuring a larger average roughness value, meeting the processing requirements of products with high roughness requirements.

[0045] Specifically, this application provides a wafer grinding method and a wafer grinding apparatus. The wafer grinding apparatus includes: a wafer carrier disk for carrying a wafer; a grinding wheel including multiple grinding components for grinding the wafer on the wafer carrier disk; a first driving mechanism and a second driving mechanism, which drive the grinding wheel and the wafer carrier disk to rotate based on preset fine grinding parameters, so as to grind the surface of the wafer through the grinding components of the grinding wheel. The fine grinding parameters include the rotational speed n1 of the grinding wheel and the rotational speed n2 of the carrier disk when fine grinding the wafer.

[0046] The wafer grinding method using this type of wafer grinding equipment includes the following steps: placing the wafer on the surface of the wafer carrier disk of the wafer grinding equipment; obtaining preset fine grinding parameters, which include the rotational speed n1 of the grinding wheel and the rotational speed n2 of the wafer carrier disk during fine grinding of the wafer; controlling the rotation of the grinding wheel and the wafer carrier disk based on the fine grinding parameters, so as to grind the surface of the wafer through the grinding component of the grinding wheel, wherein, during fine grinding of the wafer, the rotation direction of the grinding wheel and the wafer carrier disk is the same, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.025. This application improves the roughness at the concentration spot location by designing the relationship between the rotational speed of the grinding wheel and the rotational speed of the wafer carrier disk during wafer grinding, resulting in higher uniformity of overall wafer roughness after grinding, while ensuring a larger average roughness value, which can meet the processing needs of products with high roughness requirements.

[0047] The following detailed description, in conjunction with the accompanying drawings, illustrates the implementation of the wafer grinding method and wafer grinding equipment in one embodiment. It is understood that the drawings and the following description are merely illustrative and not intended to limit the scope of protection of this application. Furthermore, the drawings are merely schematic illustrations of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore, repeated descriptions of them will be omitted. This application can be embodied in many different forms and is not limited to the embodiments described herein.

[0048] like Figure 4 and Figure 5 As shown in one embodiment of this application, the wafer 30 polishing apparatus includes: a wafer carrier disk 20 for carrying a wafer 30; a polishing wheel 10 including a plurality of polishing components 11, the polishing components 11 being disposed on the side of the polishing wheel 10 facing the wafer carrier disk 20, for polishing the wafer 30 on the wafer carrier disk 20; a first driving mechanism (not shown) for driving the polishing wheel 10 to rotate; and a second driving mechanism (not shown) for driving the wafer 30 polishing apparatus to rotate. During polishing, the wafer 30 is placed on the wafer carrier disk 20 with its surface to be polished (e.g., surface C) facing the polishing components 11 of the polishing wheel 10. The first driving mechanism and the second driving mechanism are, for example, drive motors. The first driving mechanism drives the rotating shaft of the polishing wheel 10 to rotate at a set speed, and the second driving mechanism drives the rotating shaft of the wafer carrier disk 20 to rotate at a set speed. When grinding the wafer 30, the first driving mechanism and the second driving mechanism respectively drive the grinding wheel 10 and the wafer carrier disk 20 to rotate in the same direction, and the rotational speed of the wafer carrier disk 20 is less than the rotational speed of the grinding wheel 10.

[0049] During the fine grinding stage, if the grinding wheel speed is reduced to meet the wafer surface roughness requirements, the grinding force will increase if the speed of the wafer carrier disk is not adjusted. Since the hardness of the concentration spot area is lower, the surface roughness after grinding is lower than other areas; therefore, the grinding force needs to be reduced in this case. The grinding force and other parameters satisfy the following formula:

[0050]

[0051] Among them, F t Let r2 be the grinding force of a grinding component, r2 be the wafer radius, and f be the grinding force. t The grinding force of a single abrasive grain, N e For effective cutting edge density, l is the length of the grinding component, w is the width of the grinding component, R1 is the radius of the grinding wheel, Cp is the set grinding pressure, n1 is the grinding wheel speed, n2 is the wafer carrier disk speed, and Δ is the grinding depth, which is affected by the spindle speed and feed rate.

[0052] From the above formula, we can see that F t It is directly proportional to the speed ratio n2 / n1. Therefore, reducing the speed ratio n2 / n1 can reduce the grinding force F. t Therefore, this application proposes a novel solution that reduces the grinding force F while satisfying the overall surface roughness of the wafer by designing a reasonable range of rotational speed ratio n2 / n1. t In this embodiment, the first driving member and the second driving member drive the grinding wheel and the wafer carrier disk to rotate based on preset fine grinding parameters, so as to grind the surface of the wafer through the grinding component of the grinding wheel. The fine grinding parameters include the rotational speed n1 of the grinding wheel and the rotational speed n2 of the carrier disk when fine grinding the wafer. Specifically, when fine grinding the wafer, the grinding wheel and the wafer carrier disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1 ± 0.025.

[0053] Therefore, by employing this wafer grinding equipment, a new rotational speed ratio range between the grinding wheel and the wafer carrier disk is provided for fine grinding, improving the roughness at the concentration spot location and resulting in higher overall wafer roughness uniformity after grinding, which can meet the processing needs of products with high roughness requirements. The wafer grinding method and equipment of this application can effectively overcome the influence of the concentration spot region on roughness uniformity when used for grinding wafers on silicon carbide substrates, achieving excellent grinding results. However, this application is not limited to this; the equipment can also be used to grind other types of wafers.

[0054] like Figure 6 As shown in the embodiments of this application, a wafer grinding method is also provided, including the following steps:

[0055] S100: Place the wafer on the surface of the wafer carrier tray of the wafer grinding equipment;

[0056] After placing the wafer on the surface of the wafer carrier, the surface of the wafer to be ground (such as the C-side) is positioned facing the grinding component of the grinding wheel;

[0057] S200: Obtain preset fine grinding parameters, the fine grinding parameters including the rotational speed n1 of the grinding wheel of the wafer grinding equipment and the rotational speed n2 of the wafer carrier disk when fine grinding the wafer;

[0058] S300: Based on the fine grinding parameters, the grinding wheel and the wafer carrier disk are controlled to rotate, so as to grind the surface of the wafer through the grinding component of the grinding wheel. During fine grinding of the wafer, the grinding wheel and the wafer carrier disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.025. As analyzed above, the smaller the rotational speed ratio n2 / n1, the lower the corresponding grinding force, which is beneficial to improving the roughness of the concentration spot area, thereby improving the overall surface roughness uniformity of the wafer after grinding. Furthermore, the rotational speed ratio n2 / n1 should not be set too small, otherwise it will also adversely affect the wafer surface grinding effect. In this embodiment, the rotational speed ratio n2 / n1 is set to 0.1±0.025 during fine grinding to meet the overall surface roughness requirements of the wafer while reducing the grinding force.

[0059] Figure 6 The flowchart shown is merely an illustrative example and does not necessarily include all steps. For example, some steps may be broken down, while others may be combined or partially combined. Therefore, the actual execution order may change depending on the specific circumstances.

[0060] This application is the first to discover the influence of concentration spot regions on the roughness distribution of the grinding process. Existing technologies generally assume that only the center and edges differ in the roughness distribution after grinding, failing to recognize the uneven roughness distribution caused by concentration spot regions. This application provides quantitative evidence and, combined with model theory, optimizes the rotational speed of the wafer carrier disk, providing a new rotational speed ratio range between the grinding wheel and the wafer carrier disk during fine grinding. This improves the roughness at the concentration spot location, resulting in higher overall wafer roughness uniformity after grinding, while ensuring a larger average roughness value, meeting the processing needs of products with high roughness requirements. The wafer grinding method and equipment of this application effectively overcome the influence of concentration spot regions on roughness uniformity when used for grinding silicon carbide substrate wafers, achieving excellent grinding results. However, this application is not limited to this; the method can also be used to grind other types of wafers.

[0061] In this embodiment, when fine grinding the wafer, the rotational speed n1 of the grinding wheel is 2000 rpm ± 500 rpm. More optionally, the rotational speed n1 of the grinding wheel is 2000 rpm. By designing the rotational speed n1 of the grinding wheel during fine grinding, it is beneficial to meet the surface roughness requirements of some semiconductor products after wafer fine grinding. The grinding wheel rotational speed here is merely an example and is not intended to limit the scope of protection of this application. For example, in different embodiments, the rotational speed of the grinding wheel may also be 1800 rpm, 2300 rpm, 2400 rpm, etc.

[0062] In this embodiment, when the wafer is finely ground, the rotational speed n2 of the wafer carrier disk is 200 rpm ± 50 rpm. Further optionally, the rotational speed n2 of the wafer carrier disk is 200 rpm.

[0063] In this embodiment, for silicon carbide substrate wafers, the grinding wheel speed n1 during fine grinding was set to 2000 rpm, and grinding experiments were conducted using different wafer carrier disk speeds n2. The experimental results are as follows: Figure 3 , 7 As shown in Figures 8 and 9. Figure 3 The diagram shows the surface roughness distribution of the wafer after fine grinding when the grinding wheel speed n1 is set to 2000 rpm and the wafer carrier disk speed n2 is set to 275 rpm.

[0064] Figure 7 The diagram shows the surface roughness distribution of the wafer after fine grinding when the grinding wheel speed n1 is set to 2000 rpm and the wafer carrier disk speed n2 is set to 200 rpm. Figure 8 This diagram illustrates the surface roughness distribution of the wafer after fine grinding, with the grinding wheel speed n1 set to 2000 rpm and the wafer carrier disk speed n2 set to 125 rpm. (Comparison) Figure 3 , Figure 7 and Figure 8 It can be seen that reducing the rotational speed n2 of the wafer carrier disk increases the surface roughness of the wafer corresponding to the concentration spot region, further improving the overall surface roughness uniformity of the wafer. Further measurement and calculation of the wafer surface roughness yields the following comparison table:

[0065] Table 1 Comparison of wafer surface roughness parameters after fine grinding using different wafer carrier disk rotation speeds.

[0066]

[0067]

[0068] As mentioned above, when the grinding wheel speed n1 is 2000 rpm and the wafer carrier disk speed n2 is 275 rpm, 200 rpm, and 125 rpm, the average thickness, roughness range, total thickness deviation, and warpage are all within the process requirements. Figure 3 , Figure 7 and Figure 8 It can be seen that, with the grinding wheel speed n1 remaining constant, continuously reducing the wafer carrier disk speed n2, i.e., reducing the n2 / n1 ratio, can reduce the grinding force and improve the roughness of the concentration spot area. However, if the wafer carrier disk speed n2 is reduced excessively (e.g., reduced to 125 rpm), such as... Figure 8As shown in Table 1, this results in excessively high roughness at the wafer edge, which negatively impacts wafer warpage. When the wafer carrier disk rotation speed n2 is 200 rpm, the roughness range and standard deviation are optimal, while other parameters remain within controllable ranges. Therefore, reducing the wafer carrier disk rotation speed n2 to approximately 200 rpm can improve the roughness distribution of the silicon carbide substrate wafer after grinding, resulting in a more uniform overall surface roughness distribution.

[0069] Therefore, the method and apparatus of this application improve the roughness difference between the concentration spot region and the normal region, reduce the risk of back gold peeling, and provide a wider range of process ideas for controlling characterization parameters such as roughness and warpage of silicon carbide substrate wafers.

[0070] In this embodiment, before step S200: obtaining the preset fine grinding parameters, the following steps are also included:

[0071] Obtain preset coarse grinding parameters, which include the rotational speed of the grinding wheel and the rotational speed of the wafer support disk when coarse grinding the wafer;

[0072] The grinding wheel and the wafer carrier disk are rotated based on the coarse grinding parameters so as to grind the surface of the wafer through the grinding component of the grinding wheel.

[0073] In this embodiment, a wafer grinding device is used to perform coarse grinding on the wafer. During coarse grinding, the grinding wheel and the wafer support disk rotate in the same direction, and the rotational speed of the grinding wheel is greater than n1. During fine grinding, the grinding wheel rotational speed is 2000 rpm ± 500 rpm, and during coarse grinding, the grinding wheel rotational speed is 3000 rpm ± 500 rpm. For example, the grinding wheel rotational speed is 3000 rpm during coarse grinding and 2000 rpm during fine grinding. The grinding wheel rotational speeds here are merely examples and are not intended to limit the scope of this application. During coarse grinding, the rotational speed of the wafer support disk can be set as needed, for example, to 275 rpm, 270 rpm, 280 rpm, etc., and this application does not impose any limitations on this.

[0074] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0075] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the scope of protection of this patent application should be determined by the scope defined in the claims.

Claims

1. A wafer grinding method, characterized in that, include: Place the wafer on the surface of the wafer carrier tray of the wafer grinding equipment; Obtain preset fine grinding parameters, which include the rotational speed n1 of the grinding wheel of the wafer grinding equipment and the rotational speed n2 of the wafer carrier disk when fine grinding the wafer; The grinding wheel and the wafer carrier disk are controlled to rotate based on the fine grinding parameters so as to grind the surface of the wafer through the grinding component of the grinding wheel. When the wafer is finely ground, the grinding wheel and the wafer carrier disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.

025. The grinding force of the grinding wheel satisfies the following formula: ； Among them, F t Let r2 be the grinding force of a grinding component, r2 be the wafer radius, and f be the grinding force of a grinding component. t The grinding force of a single abrasive grain, N e For effective cutting edge density, l is the length of the grinding component, w is the width of the grinding component, R1 is the radius of the grinding wheel, Cp is the set grinding pressure, n1 is the grinding wheel speed, n2 is the wafer carrier disk speed, and Δ is the grinding depth.

2. The wafer grinding method according to claim 1, characterized in that, When the wafer is finely ground, the rotational speed n1 of the grinding wheel is 2000 rpm ± 500 rpm.

3. The wafer grinding method according to claim 2, characterized in that, When the wafer is finely ground, the rotational speed n2 of the wafer carrier disk is 200 rpm ± 50 rpm.

4. The wafer grinding method according to claim 2, characterized in that, The grinding wheel has a rotational speed n1 of 2000 rpm, and the wafer carrier disk has a rotational speed n2 of 200 rpm.

5. The wafer grinding method according to claim 1, characterized in that, Before obtaining the preset fine grinding parameters, the following steps are also included: Obtain preset coarse grinding parameters, which include the rotational speed of the grinding wheel and the rotational speed of the wafer support disk when coarse grinding the wafer; The grinding wheel and the wafer carrier disk are rotated based on the coarse grinding parameters so as to grind the surface of the wafer through the grinding component of the grinding wheel.

6. The wafer grinding method according to claim 5, characterized in that, During the rough grinding of the wafer, the grinding wheel and the wafer support disk rotate in the same direction, and the rotational speed of the grinding wheel is greater than n1.

7. The wafer grinding method according to claim 6, characterized in that, When coarsely grinding the wafer, the grinding wheel rotates at a speed of 3000 rpm ± 500 rpm.

8. The wafer grinding method according to claim 1, characterized in that, Used for grinding wafers with silicon carbide substrates.

9. A wafer grinding device, characterized in that, include: Wafer carrier disk, used to hold wafers; The grinding wheel includes multiple grinding components, which are disposed on the side of the grinding wheel facing the wafer carrier disk and are used to grind the wafer on the wafer carrier disk; The first drive mechanism and the second drive mechanism drive the grinding wheel and the wafer carrier disk to rotate based on preset fine grinding parameters, so as to grind the surface of the wafer through the grinding component of the grinding wheel. The fine grinding parameters include the rotational speed n1 of the grinding wheel and the rotational speed n2 of the carrier disk when fine grinding the wafer. During the fine grinding of the wafer, the grinding wheel and the wafer support disk rotate in the same direction, and the fine grinding parameters satisfy n2 / n1 equals 0.1±0.025; The grinding force of the grinding wheel satisfies the following formula: ； Among them, F t Let r2 be the grinding force of a grinding component, r2 be the wafer radius, and f be the grinding force of a grinding component. t The grinding force of a single abrasive grain, N e For effective cutting edge density, l is the length of the grinding component, w is the width of the grinding component, R1 is the radius of the grinding wheel, Cp is the set grinding pressure, n1 is the grinding wheel speed, n2 is the wafer carrier disk speed, and Δ is the grinding depth.

10. The wafer grinding equipment according to claim 9, characterized in that, When the wafer is finely ground, the rotational speed n1 of the grinding wheel is 2000 rpm ± 500 rpm, and the rotational speed n2 of the wafer carrier disk is 200 rpm ± 50 rpm.

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