A method for improving the thickness uniformity of wafer electroplating

Abstract

The application provides a method for improving the thickness uniformity of wafer electroplating, which comprises the following steps: electroplating a wafer in an electroplating cavity containing a diffusion plate; detecting the electroplating height of the wafer; inputting the electroplating height into a wafer model, dividing the wafer model into a plurality of concentric ring regions along a radial direction, and setting a plurality of concentric ring regions corresponding to the wafer model on a diffusion plate model, wherein the diffusion plate model is uniformly distributed with through holes with uniform aperture; taking an arbitrary electroplating height value as a reference value, calculating the difference between the electroplating height value of other ring regions and the reference value, and determining the electroplating height adjustment rate of each ring region; making the total area adjustment rate of the through holes in each ring region on the diffusion plate model equal to the electroplating height adjustment rate of each ring region on the wafer model, and determining the total area adjustment value of the through holes in each ring region of the diffusion plate model, so as to obtain an optimized diffusion plate model. The optimization of the diffusion plate helps to improve the electroplating quality and make the electroplating thickness of the wafer more uniform.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor manufacturing, and particularly relates to a method for improving the thickness uniformity of wafer electroplating. BACKGROUND

[0002] In the production process of semiconductor integrated circuits, a metal layer is formed on the wafer surface through electroplating. Therefore, the wafer electroplating process is as follows: the wafer is placed in an electroplating solution, a negative voltage is connected to the wafer as a cathode, and a positive voltage is connected to a soluble or insoluble anode, so that metal ions in the electroplating solution are deposited on the wafer surface through the action of an electric field. With the development of semiconductor technology, the requirement for the uniformity of wafer surface electroplating is also increasing, and a slight difference in electroplating height will affect the quality and yield of the wafer. SUMMARY

[0003] In order to realize high-quality wafer electroplating and improve the thickness uniformity of the electroplated layer, the application provides a method for improving the thickness uniformity of wafer electroplating.

[0004] The application provides a method for improving the thickness uniformity of wafer electroplating, which comprises the following steps.

[0005] Performing an electroplating process on the wafer in an electroplating cavity provided with a diffusion plate;

[0006] Detecting the electroplating height of the wafer surface after the electroplating process is completed;

[0007] Inputting the electroplating height into a wafer model, dividing the wafer model into a plurality of concentric ring regions along a radial direction, and setting a plurality of concentric ring regions corresponding to the wafer model on a diffusion plate model corresponding to the diffusion plate, wherein the diffusion plate model is uniformly distributed with through holes with uniform pore sizes;

[0008] Taking the electroplating height value of an arbitrary ring region of the wafer model as a reference value, calculating the difference between the electroplating height values of other ring regions of the wafer and the reference value, and determining the electroplating height adjustment rate of each ring region of the wafer;

[0009] Making the total area adjustment rate of the through holes in each ring region on the diffusion plate model equal to the electroplating height adjustment rate of each ring region on the wafer model, and determining the total area adjustment value of the through holes in each ring region of the diffusion plate model, so as to obtain an optimized diffusion plate model.

[0010] According to a specific implementation manner of the application, the reference value is the maximum value, the minimum value or the average value of the electroplating height of each ring region of the wafer model.

[0011] According to a specific implementation manner of the embodiment of the present application, the plurality of concentric ring regions on the wafer model are adjacent to each other and do not overlap with each other, and the common center of the plurality of concentric ring regions on the wafer model is at the center of the wafer model.

[0012] According to a specific implementation manner of the embodiment of the present application, when the total area of the through holes of a certain ring region is adjusted based on the determined total area adjustment value of the through holes of each ring region of the diffusion plate model, the total number of the through holes of the ring region is fixed and unchanged, the through holes in the ring region that need to be adjusted in aperture are defined as second through holes, the apertures of the second through holes are preset, and the apertures of the second through holes are greater than or smaller than the apertures of the first through holes; the number of the second through holes in the ring region is calculated, so that the adjusted electroplating height of the corresponding ring region on the wafer model reaches the reference value.

[0013] According to a specific implementation manner of the embodiment of the present application, the calculation of the number of the through holes that need to be adjusted in the ring region comprises:

[0014] The number n of the second through holes that need to be adjusted in aperture is calculated by using the following formula one:

[0015]

[0016] Wherein, n is the number of the second through holes that need to be adjusted in aperture;

[0017] s i is the initial total area of the through holes of the ring region;

[0018] h i is the electroplating height of the ring region and the corresponding ring region on the wafer model;

[0019] h0 is the reference value of the wafer electroplating height;

[0020] r2 is the radius of the adjusted second through hole;

[0021] r1 is the radius of the first through hole in the ring region.

[0022] According to a specific implementation manner of the embodiment of the present application, the number of the through holes that need to be adjusted is less than the number of the through holes in the ring region.

[0023] According to a specific implementation manner of the embodiment of the present application, the through holes that need to be adjusted in aperture are uniformly distributed in the ring region that needs to be adjusted.

[0024] According to a specific implementation manner of the embodiment of the present application, the through holes that need to be adjusted in aperture are uniformly distributed in at least two quadrants of the diffusion plate, and the second through holes in each quadrant are symmetrically arranged about the center of the diffusion plate.

[0025] According to a specific implementation manner of the embodiment of the present application, the method further comprises: when adjusting the total area of the through holes in a certain ring region based on the determined total area adjustment value of the through holes in each ring region of the diffusion plate model, fixing the unchanged aperture of the through holes in the ring region, calculating the number of the through holes needed in the ring region, so that the adjusted plating height of the corresponding ring region of the wafer model in the ring region reaches the reference value.

[0026] According to a specific implementation manner of the embodiment of the present application, the calculating the number of the through holes needed in the ring region comprises:

[0027] The number N of the through holes needed in the ring region is calculated by using the following formula two:

[0028]

[0029] N is the number of the through holes needed in the adjusted ring region;

[0030] s i is the initial total area of the through holes in the ring region;

[0031] h i is the plating height of the corresponding ring region of the wafer model in the ring region;

[0032] h0 is the reference value of the wafer plating height;

[0033] r is the radius of the through hole on the diffusion plate model;

[0034] n0 is the initial number of the through holes in the adjusted ring region.

[0035] The method for improving the uniformity of wafer plating thickness provided by the present application is helpful to the plating effect of the plating equipment on the wafer by optimizing the diffusion plate, so that the wafer plating thickness is more uniform.

[0036] Meanwhile, when optimizing the diffusion plate and adjusting the total area of the through holes in certain regions of the diffusion plate, the apertures of all the through holes in the region are not uniformly adjusted in size, but a certain number of through holes in the region are selected for size adjustment, so as to achieve the purpose of adjusting the total area of the through holes. The method provided by the present application can concentrate the size to be adjusted on a preset number of through holes, has the advantage of facilitating processing, and can facilitate the control of processing precision, thereby effectively guaranteeing the uniformity of the plating thickness.

[0037] In addition, the application optimizes the diffusion plate in the electroplating equipment by arranging the through holes which need to adjust the aperture size uniformly in the adjustment area of the diffusion plate, or distributing the through holes which need to adjust the aperture size in at least two quadrants of the diffusion plate, and adjusting the aperture size of the through holes which are symmetrically arranged about the center of the diffusion plate, so as to ensure that each area of the wafer receives more appropriate flow of electroplating solution during the electroplating process, thereby ensuring the uniformity of the electroplating thickness.

[0038] Other features and advantages of the present application will be set forth in the description that follows, and in part will be apparent from the description, or can be learned by practice of the present application. The purposes and other advantages of the present application will be realized and attained by the structures particularly pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0040] Figure 1 A structure schematic diagram of an electroplating equipment according to an embodiment of the present application is shown;

[0041] Figure 2 A flowchart schematic diagram of a method for improving the uniformity of wafer electroplating thickness according to an embodiment of the present application is shown;

[0042] Figure 3 A structure schematic diagram of wafer area division according to an embodiment of the present application is shown;

[0043] Figure 4 A structure schematic diagram of a diffusion plate according to an embodiment of the present application is shown;

[0044] Figure 5 A wafer surface electroplating height detection result before optimization of a diffusion plate according to an embodiment of the present application is shown;

[0045] Figure 6 A second through hole distribution schematic diagram according to an embodiment of the present application is shown;

[0046] Figure 7 Another second through hole distribution schematic diagram according to an embodiment of the present application is shown; and

[0047] Figure 8 A wafer surface electroplating height detection result after optimization of a diffusion plate according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0048] In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0049] Please refer to Figure 1 The electroplating device relates to an electroplating cavity 100, a wafer holding device 200 and a diffusion plate 300. The electroplating cavity 100 is configured to contain an electroplating solution. The wafer holding device 200 is configured to hold a wafer 400, so that the surface of the wafer 400 to be electroplated is located in the electroplating solution during electroplating. The diffusion plate 300 is arranged in the electroplating cavity 100. During the electroplating process, the electroplating solution is uniformly distributed and sprayed to the surface of the wafer 400 to be electroplated by the rectifying action of the diffusion plate 300, so that the electroplating thickness of the wafer 400 is uniform.

[0050] It is found in actual process that the electroplating height of the wafer 400 is not uniform. To this end, the present application proposes a method for improving the uniformity of the electroplating thickness of the wafer, which improves the uniformity of the electroplating thickness of the wafer by optimizing the diffusion plate.

[0051] Please refer to Figure 2 The method comprises the following steps:

[0052] Step S100: performing electroplating process on the wafer in the electroplating cavity provided with the diffusion plate.

[0053] Step S200: detecting the electroplating height of the wafer surface after the electroplating process is completed.

[0054] Step S300: inputting the electroplating height into a wafer model, dividing the wafer model into a plurality of concentric ring regions along the radial direction of the wafer, and setting a plurality of concentric ring regions corresponding to the wafer model on a diffusion plate model corresponding to the diffusion plate, wherein the diffusion plate model is uniformly distributed with through holes with uniform aperture.

[0055] The wafer model 400' and the diffusion plate model 300' are digital models. The wafer model 400' and the diffusion plate model 300' are converted from the wafer 400 and the diffusion plate 300 in the physical system into digital wafer model 400' and diffusion plate model 300' by digital twin technology or 3D modeling technology. The essence is a digital model. Based on the generated digital model, simulation, analysis and prediction can be performed.

[0056] In the area division of the wafer model 400', the wafer model 400' is divided into a plurality of concentric ring areas along the radial direction, the plurality of concentric ring areas are adjacent to each other and do not overlap with each other, and the common center of the plurality of concentric ring areas is at the center of the wafer model 400'. For details, please refer to Figure 3 , the wafer model 400' after the division includes a ring area 401, a ring area 402, a ring area 403, a ring area 404, a ring area 405, a ring area 406, a ring area 407, and a ring area 408. For details, please refer to Figure 4 , the diffusion plate model 300' includes a ring area 301, a ring area 302, a ring area 303, a ring area 304, a ring area 305, a ring area 306, a ring area 307, and a ring area 308.

[0057] Step S400: Taking the plating height value of any ring area of the wafer model as a reference value, calculating the difference between the plating height values of other ring areas of the wafer and the reference value, and determining the plating height adjustment rate of each ring area of the wafer.

[0058] Specifically, the plating height values of each ring area in the wafer model 400' are obtained, and the plating height value of any ring area is selected as the reference value. In this embodiment, only one plating height value can be detected for each ring area. As an example, the reference value is the maximum value, the minimum value, or the average value of the plating height values of each ring area. When selecting, in order to facilitate the unified adjustment of the diffusion plate, the plating height with the maximum value is preferentially selected as the reference value. As an example, the plating height with the maximum value is selected as the reference value, and the area on the wafer model 400' where the reference value is located is determined. In this embodiment, the reference value is in the ring area 401, and the difference between the plating height of each ring area and the reference value is calculated, and the plating height adjustment rate of each ring area of the wafer model 400' is determined.

[0059] wherein the plating height adjustment rate

[0060] k i is the plating height adjustment rate of the selected ring area; h0 is the reference value of the plating height; h i is the plating height value of the selected ring area.

[0061] Step S500: The total area adjustment rate of the through hole of each ring area on the diffusion plate model is equal to the plating height adjustment rate of each ring area on the wafer model, and the total area adjustment value of the through hole of each ring area of the diffusion plate model is determined to obtain an optimized diffusion plate model.

[0062] The optimized diffusion plate model is used to adjust the diffusion plate 300 in the physical system, so that the diffusion plate in the electroplating equipment conforms to the scheme involved in the optimized diffusion plate model, and the electroplating height of each ring area of the wafer reaches the reference value.

[0063] Specifically, according to the electroplating height adjustment rate k of each ring area of the wafer model 400' i The total area of the through hole of each ring area of the diffusion plate model 300' is adjusted according to the principle that the total area of the through hole of each ring area of the diffusion plate model 300' is equal to the total area of the through hole of the corresponding ring area of the wafer model 400'. m (k i =k m ) is equal. Δs is the total area of the through hole of the ring area to be adjusted; s i is the initial total area of the through hole of the ring area. Accordingly, the total area of the through hole of the selected ring area to be adjusted Δs=k m *s i =k i *s i .

[0064] It should be understood that the adjustment of the total area of the through hole of each ring area can be adjusting the aperture size of the through hole in the ring area, or adjusting the number of through holes in the ring area.

[0065] For example, in one embodiment, when adjusting the total area of the through hole of a certain ring area of the diffusion plate model 300', the total number of through holes in the ring area is fixed, the through hole in the ring area whose aperture needs to be adjusted is defined as the second through hole, the aperture of the second through hole is preset, and the aperture of the second through hole is greater than or less than the aperture of the first through hole; then the number of the second through holes in the ring area is calculated to make the adjusted electroplating height of the corresponding ring area of the wafer model 400' reach the reference value. The number n of the second through holes whose aperture needs to be adjusted is calculated by using the following formula one:

[0066]

[0067] Wherein, n is the number of the second through hole whose aperture needs to be adjusted;

[0068] s i is the initial total area of the through hole of the ring area;

[0069] h i is the electroplating height of the corresponding ring area of the wafer model;

[0070] h0 is the reference value of the wafer electroplating height;

[0071] r2 is the radius of the second via in the adjusted state;

[0072] r1 is the radius of the first via in the ring area.

[0073] It should be understood that when the plating height adjustment rate k i of a certain ring area on the wafer model 400' is 0, the plating height of the ring area does not need to be adjusted. Correspondingly, the total via area adjustment rate k m of the corresponding ring area of the diffusion plate model 300' is also 0, and the number of vias n that need to be adjusted in the ring area is 0, indicating that the total via area of the ring area does not need to be adjusted. Please refer to Figure 5 , in the embodiment of the present application, the ring area 301 of the diffusion plate model 300' is the ring area corresponding to the ring area where the reference value of the wafer model 400' is located, and the ring area 301 does not need to adjust the total via area, the plating height of the ring area 402, the ring area 403, the ring area 404, the ring area 405, the ring area 406, and the ring area 407 of the wafer 400 is equal to the plating height of the ring area 401, that is, the plating height adjustment rate k i of the ring area 402, the ring area 403, the ring area 404, the ring area 405, the ring area 406, and the ring area 407 is 0, and the plating height in these ring areas does not need to be adjusted, therefore, the total via area in the ring area 302, the ring area 303, the ring area 304, the ring area 305, the ring area 306, and the ring area 307 of the diffusion plate model 300' also does not need to be adjusted. The plating height value in the ring area 408 of the wafer model 400' is different from the reference value, and needs to be adjusted to the reference value, therefore, the total via area of the ring area 308 of the diffusion plate model 300' is adjusted, and the specific adjustment method is based on the above steps S400 and S500, which will not be repeated here. After calculating the number of second vias that need to be adjusted, the adjustment is carried out in the ring area 308 of the diffusion plate model 300', and during the adjustment, the vias with the adjusted aperture are uniformly distributed in the ring area of the adjusted ring area, so that the diffusion plate prepared according to the optimized diffusion plate model can provide a corresponding flow of plating solution to the plating surface of the wafer 400 during the plating process, and the plating height of the wafer 400 plating surface is more uniform. For example, when it is determined that the number of second vias with adjusted aperture in the ring area 308 is n = 8, a certain number of second vias 3081 are uniformly distributed in the ring area 308, please refer to Figure 6 . It should be understood that after obtaining the optimized diffusion plate model, the actual processing of the diffusion plate 300 in the physical system can be carried out according to the optimized diffusion plate model, or a new diffusion plate 300 that meets the optimization scheme can be prepared.

[0074] In another embodiment, in order to facilitate the manufacturing process while further ensuring the uniformity of the electroplating, the second through holes 3081 with the adjusted aperture are uniformly distributed in at least two quadrants of the ring area (in this embodiment, the ring area 308) of the diffusion plate 300 where the total area of the through holes needs to be adjusted, and the second through holes 3081 in the total area of the through holes of the ring area are symmetrically arranged about the center of the diffusion plate 300. Therefore, in the simulation analysis using the diffusion plate model 300', the second through holes 3081 with the adjusted aperture are uniformly distributed in at least two quadrants of the ring area (in this embodiment, the ring area 308) of the diffusion plate model 300' where the total area of the through holes needs to be adjusted, and the second through holes 3081 in the total area of the through holes of the ring area are symmetrically arranged about the center of the diffusion plate model 300'. For details, please refer to Figure 7 .

[0075] Furthermore, in order to facilitate the manufacturing process, the number of the through holes with the adjusted size in each ring area is required to be less than the total number of the through holes in the ring area.

[0076] Please refer to Figure 8 After adjusting the total area of the through holes of the ring area 408 of the diffusion plate model 300' and uniformly distributing the second through holes with the adjusted aperture in the mode of Figure 7 , the diffusion plate 300 prepared according to the optimized diffusion plate model 300' is placed into the electroplating equipment to perform the electroplating process on the wafer again, and the electroplating height of the wafer 400 surface is detected. The detection result of the electroplating height of the wafer 400 surface is shown in Figure 8 . It can be obtained that the electroplating height of the wafer 400 surface electroplated by the optimized electroplating equipment is relatively uniform, the uniformity of the electroplating thickness is effectively improved, and the electroplating quality is further improved.

[0077] In this embodiment, when optimizing the diffusion plate model and adjusting the total area of the through holes of certain ring areas of the diffusion plate model, the aperture sizes of all the through holes in the ring areas are not uniformly adjusted, but a certain number of through holes in the ring areas are selected for size adjustment to achieve the purpose of adjusting the total area of the through holes. By the method of the present application, the sizes to be adjusted can be concentrated on the preset number of through holes, which has the advantage of facilitating the processing of the diffusion plate in the physical system, and can facilitate the control of the processing precision, thereby effectively ensuring the uniformity of the electroplating thickness.

[0078] In addition, the present application selects to arrange the through holes requiring adjustment of the aperture size uniformly in the adjustment ring area of the diffusion plate model, or to distribute the through holes requiring adjustment of the aperture size in at least two quadrants of the diffusion plate model, and to set the through holes requiring adjustment of the aperture size symmetrically about the center of the diffusion plate model in a manner that the through holes are distributed in the adjustment ring area of the diffusion plate model, so as to ensure that the diffusion plate prepared according to the optimized diffusion plate model can make the wafer receive a more appropriate flow of electroplating solution during the electroplating process of the wafer, and further ensure the uniformity of the electroplating thickness.

[0079] In another embodiment of adjusting the total area of the through holes in a certain ring area, the aperture of the through holes in the ring area is fixed, and the number of the through holes requiring adjustment in the ring area is calculated so that the adjusted electroplating height of the corresponding ring area on the wafer model 400' reaches the reference value. The number of the through holes requiring adjustment in the ring area N is calculated by using the following Formula II:

[0080]

[0081] wherein N is the number of the through holes in the adjusted ring area;

[0082] s i is the initial total area of the through holes in the ring area;

[0083] h i is the electroplating height of the corresponding ring area on the wafer model;

[0084] h0 is the reference value of the wafer electroplating height;

[0085] r is the radius of the through hole on the diffusion plate model;

[0086] n0 is the initial number of the through holes in the adjusted ring area.

[0087] After the number N of the through holes requiring adjustment in the adjusted ring area is calculated, the initial number n0 of the through holes in the adjusted ring area is adjusted. For example, when the number N of the through holes requiring adjustment in the adjusted ring area is calculated to be 105, and the initial number n0 of the through holes in the adjusted ring area is 100, then when the area of the through holes in the adjusted ring area is adjusted, the number of the through holes in the adjusted ring area needs to be adjusted from 100 to 105.

[0088] Through the optimization of the diffusion plate model in the present application, that is, the optimization of the structure of the diffusion plate in the physical system, the electroplating effect of the electroplating equipment on the wafer during the electroplating process is improved, and the electroplating thickness of the wafer is more uniform.

[0089] Although the present application has been described in detail with reference to the foregoing embodiments, it should be understood that modifications can be made to the foregoing embodiments, or additional implementations can be implemented, without departing from the spirit and scope of the inventive subject matter. Accordingly, the present application is not limited to the implementations described herein, but is intended to be defined by the claims set forth below, and equivalents thereof.

Claims

1. A method for improving the thickness uniformity of electroplating of a wafer, comprising: The application relates to a method for optimizing a diffusion plate model of a wafer electroplating process. The method comprises the following steps: carrying out the wafer electroplating process in an electroplating cavity provided with a diffusion plate; detecting the electroplating height of the wafer surface after the electroplating process is completed; inputting the electroplating height into a wafer model, dividing the wafer model into a plurality of concentric ring regions along a radial direction, and setting a plurality of concentric ring regions corresponding to the wafer model on a diffusion plate model corresponding to the diffusion plate, wherein the diffusion plate model is uniformly provided with through holes with uniform diameters; taking the electroplating height value of an arbitrary ring region of the wafer model as a reference value, calculating the difference between the electroplating height values of other ring regions of the wafer and the reference value, and determining the electroplating height adjustment rate of each ring region of the wafer; 2. The method of claim 1, wherein, making the total area adjustment rate of the through holes of each ring region on the diffusion plate model equal to the electroplating height adjustment rate of each ring region on the wafer model, and determining the total area adjustment value of the through holes of each ring region of the diffusion plate model, so as to obtain an optimized diffusion plate model.

3. The method of claim 1, wherein the seed layer is formed by sputtering. The reference value is the maximum value, the minimum value or the average value of the electroplating height of each ring region of the wafer model.

4. The method of claim 1, wherein, The plurality of concentric ring regions on the wafer model are adjacent to each other and do not overlap with each other, and the common center of the plurality of concentric ring regions on the wafer model is at the center of the wafer model. The application further comprises the following steps:

5. The method of claim 4, wherein the seed layer is formed by sputtering. when the total area of the through holes of a certain ring region is adjusted based on the determined total area adjustment value of the through holes of each ring region of the diffusion plate model, the total number of the through holes of the ring region is fixed and unchanged, the through holes in the ring region that need to adjust the diameters are defined as second through holes, the diameters of the second through holes are preset, and the diameters of the second through holes are greater than or smaller than the diameters of first through holes; the number of the second through holes in the ring region is calculated, so that the adjusted electroplating height of the corresponding ring region of the wafer model reaches the reference value. The calculation of the number of the second through holes in the ring region comprises the following steps: the number n of the second through holes that need to adjust the diameters is calculated by using the following formula one: s i A is the initial total area of the ring region via; h i the plating height of the ring area corresponding to the ring area of the wafer model; wherein n is the number of the second through holes that need to adjust the diameters; h0 is the reference value of the wafer electroplating height; r2 is the radius of the adjusted second through hole; 6. The method of claim 5, wherein the method further comprises: r1 is the radius of the first through hole in the ring region.

7. The method of claim 6, wherein the method further comprises: The number of the second through holes that need to adjust the diameters is smaller than the number of the through holes in the ring region.

8. The method of claim 6, wherein the method further comprises: The application further comprises the following step:

9. The method of claim 1, wherein, the second through holes that need to adjust the diameters are uniformly distributed in the ring region that needs to adjust the diameters. The application further comprises the following step:

10. The method of claim 9, wherein the method further comprises: the second through holes that need to adjust the diameters are uniformly distributed in at least two quadrants of the diffusion plate, and the second through holes in each quadrant are symmetrically arranged about the center of the diffusion plate. The application further comprises the following steps: when the total area of the through holes of a certain ring region is adjusted based on the determined total area adjustment value of the through holes of each ring region of the diffusion plate model, the diameters of the through holes of the ring region are fixed and unchanged, the number of the through holes in the ring region is calculated, so that the adjusted electroplating height of the corresponding ring region of the wafer model reaches the reference value. s i A is the initial total area of the ring region via; h i h0 is the base value of the wafer plating height; The calculation of the number of the through holes in the ring region comprises the following steps: the number N of the through holes in the ring region that need to adjust the diameters is calculated by using the following formula two: wherein N is the number of the through holes in the ring region that need to adjust the diameters; r is the radius of the through hole on the diffusion plate model; n0 is the initial number of the through holes in the ring region that needs to adjust the diameters.

Images