Optical thin film deposition scanning control method and system

Abstract

The invention belongs to the technical field of archive arrangement, and provides an optical thin film deposition scanning control method and system.The method comprises the steps that an optical thin film is divided into a plurality of areas, the uniformity of the optical thin film in each area is analyzed, and whether the thickness of the optical thin film is uniform or not is judged; the method comprises the following steps: dividing an area with abnormal thickness into a relatively thick area and a relatively thin area, judging whether a deposition rate is matched with a scanning speed or not, and analyzing the matching property and theoretical coincidence relation of the deposition rate and the scanning speed in the relatively thick area and the relatively thin area; whether the thickness nonuniformity of the optical thin film is caused by mismatching of the deposition rate and the scanning speed is judged, and the deposition rate and the scanning speed are adjusted according to a theoretical relationship, so that the problem that the thickness of the optical thin film is nonuniform due to mismatching of the deposition rate and the scanning speed in the deposition scanning process of the optical thin film is solved. And the quality of the optical film is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gear life assessment, and in particular relates to an optical thin film deposition scanning control method and system. Background Art

[0002] In the existing optical film deposition scanning process, the mismatch between the deposition rate and the scanning speed may lead to uneven optical film thickness. The existing technology has many problems with optical film uniformity and the adjustment of deposition rate and scanning speed. For example, when determining the uniformity of optical film thickness, the optical film is not divided into small areas for analysis, which may lead to inaccurate local uniformity judgments and difficulty in locating uneven areas. In terms of determining the cause of uneven areas, there is a lack of effective methods to analyze the matching degree and theoretical relationship between the deposition rate and scanning speed in uneven areas. It is impossible to accurately determine whether the cause of the uneven optical film thickness is the mismatch between the deposition rate and scanning speed, and thus it is impossible to accurately adjust the deposition rate and scanning speed. This may result in the problem of uneven optical film thickness remaining unresolved, resulting in low quality optical film deposition scanning.

[0003] To this end, the present invention provides an optical thin film deposition scanning control method and system. Summary of the Invention

[0004] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] An optical thin film deposition scanning control method, comprising:

[0007] Step 1: Divide the optical film into several areas to determine whether the thickness of the optical film is uniform;

[0008] Step 2: If the thickness of the optical film is uneven, each region is divided into thicker regions and thinner regions, generating a set of thicker regions and a set of thinner regions;

[0009] Step 3: Calculate the matching degree between the deposition rate and the scanning speed of the equipment to determine whether the deposition rate and the scanning speed match;

[0010] Step 4: If there is a mismatch, analyze the deposition rate and scanning speed of the thicker and thinner areas to determine whether the optical film unevenness is caused by the mismatch between the deposition rate and scanning speed;

[0011] Step 5: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, adjust the deposition rate and the scanning speed according to the theoretical relationship between the thickness of the optical film and the deposition rate and the scanning speed.

[0012] Furthermore, the process of determining whether the optical film is uniform is as follows:

[0013] Divide the optical film evenly into several areas and measure the thickness of the film in each area;

[0014] Calculate the average and standard deviation of the film thickness in all areas, and calculate the uniformity coefficient by proportionally calculating the standard deviation of the film thickness to the average value;

[0015] The uniformity coefficient is compared with a threshold value. If the uniformity coefficient is greater than or equal to the threshold value, the thickness of the optical film is uniform. If the uniformity coefficient is less than the threshold value, the thickness of the optical film is non-uniform.

[0016] Furthermore, the process of dividing each region into thicker regions and thinner regions is as follows:

[0017] The thickness of the optical film in each region is compared with the standard optical film thickness. The region where the optical film thickness is greater than the standard optical film thickness is classified as a relatively thick region, and the region where the optical film thickness is less than the standard optical film thickness is classified as a relatively thin region.

[0018] Furthermore, the process of determining whether the deposition rate matches the scanning speed is as follows:

[0019] Calculate the matching coefficient of each area, obtain the proportion of the number of mismatched areas and the fluctuation coefficient of the matching coefficient, and add the proportion of the number of mismatched areas and the fluctuation coefficient of the matching coefficient to obtain the comprehensive matching coefficient;

[0020] The comprehensive matching coefficient is compared with a threshold value. If the comprehensive matching coefficient is greater than the threshold value, the deposition rate does not match the scanning speed.

[0021] Furthermore, the calculation process of the matching coefficient and the ratio of the number of non-matching areas is as follows:

[0022] The deviation between the theoretical and measured deposition rates and the scanning speed is calculated based on the ratio of the theoretical and measured deposition rates and the scanning speed, and the deviation is the matching coefficient.

[0023] The matching coefficient of each region is compared with the threshold, and the regions with matching coefficients greater than or equal to the threshold are marked as mismatched regions. The ratio of the number of mismatched regions to the total number of regions is calculated to obtain the proportion of mismatched regions.

[0024] Furthermore, the method for determining whether the unevenness of the optical film is caused by the mismatch between the deposition rate and the scanning speed is:

[0025] For thicker areas and thinner areas, the proportion of thicker overlapping areas and the proportion of thinner overlapping areas are obtained according to the matching coefficient between deposition rate and scanning speed;

[0026] The theoretical correspondence rate was obtained by analyzing the theoretical relationship between the deposition rate and the scanning speed in the thicker overlapped area and the thinner overlapped area.

[0027] The comprehensive influence coefficient is obtained by adding the proportion of the number of thick overlapping areas, the proportion of the number of thin overlapping areas and the theoretical compliance rate;

[0028] The comprehensive influence coefficient is compared with the threshold. If the comprehensive influence coefficient is greater than the threshold, it is determined whether the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed.

[0029] Furthermore, the calculation process of the ratio of the number of thicker overlapping areas and the ratio of the number of thinner overlapping areas is as follows:

[0030] For any thick region and thin region, the regions where the deposition rate does not match the scanning speed in the thick region and the thin region are marked as thick overlap region and thin overlap region respectively;

[0031] The number of thick overlapping areas and thin overlapping areas are counted separately, and the proportion of the number of thick overlapping areas and thin overlapping areas to the total number of thick areas and thin areas is calculated to obtain the proportion of the number of thick overlapping areas and thin overlapping areas.

[0032] Furthermore, the calculation process of the theoretical compliance rate is:

[0033] For any thick overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is greater than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0034] For any thin overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is less than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0035] The number of qualified areas is counted, and the theoretical compliance rate is calculated by proportionally calculating the number of qualified areas and the total number of thick overlapping areas and thin overlapping areas.

[0036] Furthermore, the process of adjusting the deposition rate and the scanning speed is as follows:

[0037] If the measured deposition rate is equal to the theoretical deposition rate, only the scanning speed is adjusted, and the adjustment amount is the difference between the theoretical scanning speed and the measured scanning speed;

[0038] If the measured scanning speed is equal to the theoretical scanning speed, only the deposition rate is adjusted, and the adjustment amount is the difference between the theoretical deposition rate and the measured deposition rate;

[0039] If the measured deposition rate and scanning speed deviate from the theoretical values, the deposition rate and scanning speed are adjusted synchronously. For thicker areas, the deposition rate and scanning speed are proportionally reduced; for thinner areas, the deposition rate and scanning speed are proportionally increased.

[0040] An optical thin film deposition scanning control system includes the following modules:

[0041] Region division and uniformity judgment module: divides the optical film into several regions and determines whether the thickness of the optical film is uniform;

[0042] Abnormal thickness area classification module: If the thickness of the optical film is uneven, each area is divided into thicker areas and thinner areas, and a set of thicker areas and a set of thinner areas are generated;

[0043] Deposition parameter matching analysis module: calculates the matching degree between the deposition rate and scanning speed of the equipment, and determines whether the deposition rate and scanning speed match;

[0044] Non-uniformity cause correlation verification module: If there is a mismatch, the deposition rate and scanning speed of the thicker and thinner areas are analyzed to determine whether the optical film non-uniformity is caused by the mismatch between the deposition rate and scanning speed;

[0045] Deposition parameter coordinated adjustment module: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, the deposition rate and the scanning speed are adjusted according to the theoretical relationship between the thickness of the optical film and the deposition rate and the scanning speed.

[0046] The beneficial effects of the present invention are as follows:

[0047] By dividing the optical film into several areas and analyzing the thickness of the optical film in each area to determine whether the thickness of the optical film is uniform, identifying the abnormal thickness area, analyzing the matching relationship and theoretical compliance relationship between the deposition rate and the scanning speed in the abnormal thickness area, and adjusting the deposition rate and the scanning speed according to the theoretical relationship between the optical film thickness and the deposition rate and the scanning speed, the problem of uneven thickness of the optical film caused by the mismatch between the deposition rate and the scanning speed during the optical film deposition scanning process is solved, thereby improving the quality of the optical film. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The present invention will be further described below with reference to the accompanying drawings.

[0049] Figure 1 This is a flowchart of the steps of an optical thin film deposition scanning control method according to an embodiment of the present invention;

[0050] Figure 2 This is a logic judgment diagram of an optical thin film deposition scanning control method according to an embodiment of the present invention;

[0051] Figure 3 It is a flowchart of an optical thin film deposition scanning control system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0053] Example 1

[0054] See also Figure 1 As shown, an optical thin film deposition scanning control method according to an embodiment of the present invention includes the following steps:

[0055] Step 1: Divide the optical film into several areas to determine whether the thickness of the optical film is uniform;

[0056] In step 1, the process of evenly dividing the optical film into a plurality of regions includes:

[0057] According to the size of the optical film and the detection accuracy requirements, the optical film is evenly divided into several areas;

[0058] Among them, optical films of different shapes can be divided according to different classification methods, for example:

[0059] For rectangular optical films, the grid division method is used to divide the optical film into equal intervals in the horizontal and vertical directions to form regular rectangular grid areas. By setting an appropriate number of grids, the accuracy of the data can be guaranteed without making the calculation too complicated. After division, each area has a clear location mark, which is convenient for subsequent measurement and analysis.

[0060] For circular optical films, concentric circles and radial lines are used to divide the optical film into multiple annular and sector-shaped areas. First, the center of the circle is determined, and concentric circles with different radii are drawn to form annular belts. Then, radial lines are drawn from the center of the circle to divide the annular belts so that the area of ​​each area is as equal as possible. This division facilitates the analysis of the thickness variation trend of the optical film from the center to the edge.

[0061] In step 1, the process of determining whether the thickness of the optical film is uniform includes:

[0062] Use a spectroscopic ellipsometer to measure the thickness of the optical film in each area. Select 3-5 measurement points in each area for measurement, and take the average value as the thickness of the optical film in that area.

[0063] Calculate the average and standard deviation of the optical film thickness in all regions, calculate the uniformity coefficient by proportionally calculating the standard deviation of the optical film thickness to the average value, and compare the uniformity coefficient with a threshold value. If the uniformity coefficient is greater than or equal to the threshold value, the optical film thickness is non-uniform; if the uniformity coefficient is less than the threshold value, the optical film thickness is uniform.

[0064] Step 2: If the thickness of the optical film is uneven, each region is divided into thicker regions and thinner regions, generating a set of thicker regions and a set of thinner regions;

[0065] In step 2, the process of dividing each region into thicker regions and thinner regions includes:

[0066] The optical film is divided into N grids horizontally and M grids vertically. Each grid area is represented by a two-dimensional index (i, j), where i is the horizontal index and j is the vertical index.

[0067] Compare the thickness of the optical film in each region with the standard optical film thickness, and classify the region where the optical film thickness is greater than the standard optical film thickness as a relatively thick region, and the region where the optical film thickness is less than the standard optical film thickness as a relatively thin region;

[0068] Generate a set of thicker regions and a set of thinner regions respectively, each set containing a two-dimensional index label and the thickness of the optical film for each region;

[0069] Step 3: Calculate the matching coefficient between the deposition rate and the scanning speed of the equipment to determine whether the deposition rate and the scanning speed match;

[0070] Obtain the actual measured deposition rate and scanning speed of each area, calculate the ratio, and calculate the matching coefficient of each area based on the ratio of the theoretical deposition rate and scanning speed. Where, (R / v) 实测i,j =h 实测i,j / t i,j , is the ratio of the measured deposition rate to the scanning speed in the (i, j) region, (R / v) 理论 =R 理论 / v 理论 , is the theoretical ratio of deposition rate to scanning speed, where the matching coefficient measures the degree to which the ratio of measured deposition rate to scanning speed deviates from the theoretical value;

[0071] Compare the matching coefficient of each region with the threshold, mark the region with a matching coefficient greater than or equal to the threshold as a mismatched region, and calculate the ratio of the number of mismatched regions to the total number of regions to obtain the proportion of mismatched regions;

[0072] Calculate the mean and standard deviation of the matching coefficient of each region, and calculate the ratio of the mean and standard deviation to obtain the fluctuation coefficient of the matching coefficient of each region;

[0073] The proportion of the number of mismatched areas is added to the fluctuation coefficient to obtain a comprehensive matching coefficient, which is then compared with a threshold. If the comprehensive matching coefficient is greater than the threshold, the deposition rate does not match the scanning speed.

[0074] It can be understood that the physical meaning of the comprehensive matching coefficient is to reflect the matching consistency and fluctuation degree of the deposition rate and the scanning speed in the global range. The larger the comprehensive matching coefficient, the more serious the matching problem between the deposition rate and the scanning speed.

[0075] For example, assuming a rectangular optical film is divided into 5×5=25 regions, the theoretical deposition rate Rtheory=10 nm / s, the theoretical scanning speed vtheory=2 nm / s, the ratio is 2, the matching coefficient threshold δ is 20%, and the comprehensive matching coefficient threshold Γ=0.3;

[0076] Assume that the ratio of the measured deposition rate to the scanning speed in each area is:

[0077] |region(i,j)|(1,1)|(1,2)|(1,3)|(1,4)|(1,5|;

[0078] |R / v|1.5|1.8|2.0|2.2|2.5|;

[0079] |region(i,j)|(2,1)|(2,2)|(2,3)|(2,4)|(2,5)|;

[0080] |R / v|1.6|1.98|2.0|2.1|2.4|;

[0081] |...|...|...|...|...|...|;

[0082] |region(i,j)|(5,1)|(5,2)|(5,3)|(5,4)|(5,5)|;

[0083] |R / v|1.9|2.1|2.0|2.3|2.6|;

[0084] Matching coefficient calculation: Similarly, calculate the matching coefficients for all regions. Assuming there are 5 mismatched regions, the mismatch ratio = 5 / 25 = 0.2;

[0085] Calculate the fluctuation coefficient of the matching coefficient, assuming that the mean of the matching coefficient of each region is 0.108, the standard deviation is 0.085, and the fluctuation coefficient is 0.787;

[0086] Comprehensive matching coefficient = 0.2 + 0.787 = 0.987 > 0.3, judging that the deposition rate and the scanning speed do not match;

[0087] Step 4: If there is a mismatch, analyze the deposition rate and scanning speed of the thicker and thinner areas to determine whether the optical film unevenness is caused by the mismatch between the deposition rate and scanning speed;

[0088] In step 4, the process of determining whether the non-uniformity of the optical film is caused by the mismatch between the deposition efficiency and the scanning speed includes:

[0089] For any thick region or thin region, the regions where the deposition rate does not match the scanning speed in the thick region or thin region are marked as thick overlap regions or thin overlap regions, respectively. The number of thick overlap regions or thin overlap regions is counted, and the ratio of the number of thick overlap regions or thin overlap regions to the total number of thick regions or thin regions is calculated to obtain the ratio of the number of thick overlap regions or thin overlap regions.

[0090] For any thick overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is greater than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0091] For any thin overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is less than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0092] Count the number of qualified areas and calculate the ratio of the qualified areas to the total number of thick overlapping areas and thin overlapping areas to obtain the theoretical compliance rate;

[0093] The comprehensive influence coefficient is obtained by adding the proportion of the number of thick overlapping areas, the proportion of the number of thin areas, and the theoretical compliance rate. The comprehensive influence coefficient is compared with the threshold. If the comprehensive influence coefficient is greater than the threshold, it is determined whether the optical film non-uniformity is caused by the mismatch between the deposition rate and the scanning speed.

[0094] Step 5: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, adjust the deposition rate and the scanning speed according to the theoretical relationship between the thickness of the optical film and the deposition rate and the scanning speed;

[0095] In step five, the process of adjusting the deposition rate and the scanning speed includes:

[0096] If the measured deposition rate is equal to the theoretical deposition rate, only the scanning speed is adjusted, v 调整 =|v 理论 -v 实测 |;

[0097] If the measured scanning speed is equal to the theoretical scanning speed, only the deposition rate is adjusted, R 调整 =|R 理论 -R实测 |;

[0098] If the measured deposition rate and scanning speed deviate from the theoretical value, adjust the deposition rate and scanning speed synchronously to make the new ratio close to the target ratio. k is the proportionality coefficient,

[0099] For thicker areas, k<1, and the deposition rate and scanning speed are proportionally reduced. For thinner areas, k>1, and the deposition rate and scanning speed are proportionally increased.

[0100] The technical solution and benefits of the embodiments of the present application are as follows: the optical film is evenly divided into several regions, and whether the thickness of the optical film is uniform is determined. If the thickness of the optical film is uneven, each region is divided into thicker regions and thinner regions, and a set of thicker regions and a set of thinner regions are generated. The matching degree of the deposition rate and scanning speed of the device is calculated to determine whether the deposition rate and the scanning speed match. If not, the deposition rate and scanning speed of the thicker regions and the thinner regions are analyzed to determine whether the unevenness of the optical film is caused by the mismatch between the deposition rate and the scanning speed. If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, the deposition rate and the scanning speed are adjusted according to the theoretical relationship between the optical film thickness, the deposition rate and the scanning speed. The present application determines whether the thickness of the optical film is uniform by analyzing the thickness of the optical film in each region, identifies abnormal thickness regions, analyzes the matching relationship between the deposition rate and the scanning speed in the abnormal thickness region and the theoretical consistency relationship, and adjusts the deposition rate and the scanning speed according to the theoretical relationship between the optical film thickness, the deposition rate and the scanning speed, thereby solving the problem of uneven thickness of the optical film caused by the mismatch between the deposition rate and the scanning speed during the optical film deposition and scanning process, thereby improving the quality of the optical film.

[0101] Example 2

[0102] See also Figure 2 As shown, an optical thin film deposition scanning control system according to an embodiment of the present invention includes:

[0103] Region division and uniformity judgment module: divides the optical film into several regions and determines whether the thickness of the optical film is uniform;

[0104] The process of evenly dividing the optical film into a plurality of regions comprises:

[0105] According to the size of the optical film and the detection accuracy requirements, the optical film is evenly divided into several areas;

[0106] Among them, optical films of different shapes can be divided according to different classification methods, for example:

[0107] For rectangular optical films, the grid division method is used to divide the optical film into equal intervals in the horizontal and vertical directions to form regular rectangular grid areas. By setting an appropriate number of grids, the accuracy of the data can be guaranteed without making the calculation too complicated. After division, each area has a clear location mark, which is convenient for subsequent measurement and analysis.

[0108] For circular optical films, concentric circles and radial lines are used to divide the optical film into multiple annular and sector-shaped areas. First, the center of the circle is determined, and concentric circles with different radii are drawn to form annular belts. Then, radial lines are drawn from the center of the circle to divide the annular belts so that the area of ​​each area is as equal as possible. This division facilitates the analysis of the thickness variation trend of the optical film from the center to the edge.

[0109] The process of determining whether the thickness of the optical film is uniform includes:

[0110] Use a spectroscopic ellipsometer to measure the thickness of the optical film in each area. Select 3-5 measurement points in each area for measurement, and take the average value as the thickness of the optical film in that area.

[0111] Calculate the average and standard deviation of the optical film thickness in all regions, calculate the uniformity coefficient by proportionally calculating the standard deviation of the optical film thickness to the average value, and compare the uniformity coefficient with a threshold value. If the uniformity coefficient is greater than or equal to the threshold value, the optical film thickness is non-uniform; if the uniformity coefficient is less than the threshold value, the optical film thickness is uniform.

[0112] Abnormal thickness area classification module: If the thickness of the optical film is uneven, each area is divided into thicker areas and thinner areas, and a set of thicker areas and a set of thinner areas are generated;

[0113] The process of dividing each region into a relatively thick region and a relatively thin region includes:

[0114] The optical film is divided into N grids horizontally and M grids vertically. Each grid area is represented by a two-dimensional index (i, j), where i is the horizontal index and j is the vertical index.

[0115] Compare the thickness of the optical film in each region with the standard optical film thickness, and classify the region where the optical film thickness is greater than the standard optical film thickness as a relatively thick region, and the region where the optical film thickness is less than the standard optical film thickness as a relatively thin region;

[0116] Generate a set of thicker regions and a set of thinner regions respectively, each set containing a two-dimensional index label and the thickness of the optical film for each region;

[0117] Deposition parameter matching analysis module: calculates the matching coefficient between the deposition rate and scanning speed of the equipment, and determines whether the deposition rate and scanning speed match;

[0118] Obtain the actual measured deposition rate and scanning speed of each area, calculate the ratio, and calculate the matching coefficient of each area based on the ratio of the theoretical deposition rate and scanning speed. Where, (R / v) 实测i,j =h 实测i,j / t i,j , is the ratio of the measured deposition rate to the scanning speed in the (i, j) region, (R / v) 理论 =R 理论 / v 理论 , is the theoretical ratio of deposition rate to scanning speed, where the matching coefficient measures the degree to which the ratio of measured deposition rate to scanning speed deviates from the theoretical value;

[0119] Compare the matching coefficient of each region with the threshold, mark the region with a matching coefficient greater than or equal to the threshold as a mismatched region, and calculate the ratio of the number of mismatched regions to the total number of regions to obtain the proportion of mismatched regions;

[0120] Calculate the mean and standard deviation of the matching coefficient of each region, and calculate the ratio of the mean and standard deviation to obtain the fluctuation coefficient of the matching coefficient of each region;

[0121] The proportion of the number of mismatched areas is added to the fluctuation coefficient to obtain a comprehensive matching coefficient, which is then compared with a threshold. If the comprehensive matching coefficient is greater than the threshold, the deposition rate does not match the scanning speed.

[0122] It can be understood that the physical meaning of the comprehensive matching coefficient is to reflect the matching consistency and fluctuation degree of the deposition rate and the scanning speed in the global range. The larger the comprehensive matching coefficient, the more serious the matching problem between the deposition rate and the scanning speed.

[0123] Non-uniformity cause correlation verification module: If there is a mismatch, the deposition rate and scanning speed of the thicker and thinner areas are analyzed to determine whether the optical film non-uniformity is caused by the mismatch between the deposition rate and scanning speed;

[0124] The process of determining whether the unevenness of the optical film is caused by the mismatch between the deposition efficiency and the scanning speed includes:

[0125] For any thick region or thin region, the regions where the deposition rate does not match the scanning speed in the thick region or thin region are marked as thick overlap regions or thin overlap regions, respectively. The number of thick overlap regions or thin overlap regions is counted, and the ratio of the number of thick overlap regions or thin overlap regions to the total number of thick regions or thin regions is calculated to obtain the ratio of the number of thick overlap regions or thin overlap regions.

[0126] For any thick overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is greater than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0127] For any thin overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is less than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area;

[0128] Count the number of qualified areas and calculate the ratio of the qualified areas to the total number of thick overlapping areas and thin overlapping areas to obtain the theoretical compliance rate;

[0129] The comprehensive influence coefficient is obtained by adding the proportion of the number of thick overlapping areas, the proportion of the number of thin areas, and the theoretical compliance rate. The comprehensive influence coefficient is compared with the threshold. If the comprehensive influence coefficient is greater than the threshold, it is determined whether the optical film non-uniformity is caused by the mismatch between the deposition rate and the scanning speed.

[0130] Deposition parameter coordinated adjustment module: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, the deposition rate and the scanning speed are adjusted according to the theoretical relationship between the optical film thickness, the deposition rate and the scanning speed;

[0131] The process of adjusting the deposition rate and the scanning speed includes:

[0132] If the measured deposition rate is equal to the theoretical deposition rate, only the scanning speed is adjusted, v 调整 =|v 理论 -v 实测 |;

[0133] If the measured scanning speed is equal to the theoretical scanning speed, only the deposition rate is adjusted, R 调整 =|R 理论 -R 实测 |;

[0134] If the measured deposition rate and scanning speed deviate from the theoretical value, adjust the deposition rate and scanning speed synchronously to make the new ratio close to the target ratio. k is the proportionality coefficient,

[0135] For thicker areas, k<1, and the deposition rate and scanning speed are proportionally reduced. For thinner areas, k>1, and the deposition rate and scanning speed are proportionally increased.

[0136] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling optical thin film deposition scanning, characterized in that: include: Step 1: Divide the optical film into several areas to determine whether the thickness of the optical film is uniform; Step 2: If the thickness of the optical film is uneven, each region is divided into thicker regions and thinner regions, generating a set of thicker regions and a set of thinner regions; Step 3: Calculate the matching degree between the deposition rate and the scanning speed of the equipment to determine whether the deposition rate and the scanning speed match; Step 4: If there is a mismatch, analyze the deposition rate and scanning speed of the thicker and thinner areas to determine whether the uneven thickness of the optical film is caused by the mismatch between the deposition rate and scanning speed; Step 5: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, adjust the deposition rate and the scanning speed according to the theoretical relationship between the thickness of the optical film and the deposition rate and the scanning speed.

2. The optical thin film deposition scanning control method according to claim 1, characterized in that: The process of determining whether the optical film is uniform is as follows: Divide the optical film evenly into several areas and measure the thickness of the film in each area; Calculate the average and standard deviation of the film thickness in all areas, and calculate the uniformity coefficient by proportionally calculating the standard deviation of the film thickness to the average value; The uniformity coefficient is compared with a threshold value. If the uniformity coefficient is greater than or equal to the threshold value, the thickness of the optical film is uniform. If the uniformity coefficient is less than the threshold value, the thickness of the optical film is non-uniform.

3. The optical thin film deposition scanning control method according to claim 1, characterized in that: The process of dividing each area into thicker areas and thinner areas is as follows: The thickness of the optical film in each region is compared with the standard optical film thickness. The region where the optical film thickness is greater than the standard optical film thickness is classified as a relatively thick region, and the region where the optical film thickness is less than the standard optical film thickness is classified as a relatively thin region.

4. The optical thin film deposition scanning control method according to claim 1, characterized in that: The process of determining whether the deposition rate matches the scanning speed is as follows: Calculate the matching coefficient of each area, obtain the proportion of the number of mismatched areas and the fluctuation coefficient of the matching coefficient, and add the proportion of the number of mismatched areas and the fluctuation coefficient of the matching coefficient to obtain the comprehensive matching coefficient; The comprehensive matching coefficient is compared with a threshold value. If the comprehensive matching coefficient is greater than the threshold value, the deposition rate does not match the scanning speed.

5. The optical thin film deposition scanning control method according to claim 4, characterized in that: The calculation process of the matching coefficient and the ratio of the number of non-matching areas is as follows: The deviation between the theoretical and measured deposition rates and the scanning speed is calculated based on the ratio of the theoretical and measured deposition rates and the scanning speed, and the deviation is the matching coefficient. The matching coefficient of each region is compared with the threshold, and the regions with matching coefficients greater than or equal to the threshold are marked as mismatched regions. The ratio of the number of mismatched regions to the total number of regions is calculated to obtain the proportion of mismatched regions.

6. The optical thin film deposition scanning control method according to claim 1, characterized in that: The method for determining whether the unevenness of the optical film is caused by the mismatch between the deposition rate and the scanning speed is: For thicker areas and thinner areas, the proportion of thicker overlapping areas and the proportion of thinner overlapping areas are obtained according to the matching coefficient between deposition rate and scanning speed; The theoretical correspondence rate was obtained by analyzing the theoretical relationship between the deposition rate and the scanning speed in the thicker overlapped area and the thinner overlapped area. The comprehensive influence coefficient is obtained by adding the proportion of the number of thick overlapping areas, the proportion of the number of thin overlapping areas and the theoretical compliance rate; The comprehensive influence coefficient is compared with the threshold. If the comprehensive influence coefficient is greater than the threshold, it is determined whether the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed.

7. The optical thin film deposition scanning control method according to claim 6, characterized in that: The calculation process of the ratio of the number of thicker overlapping areas and the ratio of the number of thinner overlapping areas is as follows: For any thick region and thin region, the regions where the deposition rate does not match the scanning speed in the thick region and the thin region are marked as thick overlap region and thin overlap region respectively; The number of thick overlapping areas and thin overlapping areas are counted separately, and the proportion of the number of thick overlapping areas and thin overlapping areas to the total number of thick areas and thin areas is calculated to obtain the proportion of the number of thick overlapping areas and thin overlapping areas.

8. The optical thin film deposition scanning control method according to claim 6, characterized in that: The calculation process of the theoretical compliance rate is: For any thick overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is greater than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area; For any thin overlapping area, the area where the ratio of the measured deposition rate to the scanning speed is less than the ratio of the theoretical deposition rate to the scanning speed is marked as a qualified area; The number of qualified areas is counted, and the theoretical compliance rate is calculated by proportionally calculating the number of qualified areas and the total number of thick overlapping areas and thin overlapping areas.

9. The optical thin film deposition scanning control method according to claim 1, characterized in that: The process of adjusting the deposition rate and scanning speed is as follows: If the measured deposition rate is equal to the theoretical deposition rate, only the scanning speed is adjusted, and the adjustment amount is the difference between the theoretical scanning speed and the measured scanning speed; If the measured scanning speed is equal to the theoretical scanning speed, only the deposition rate is adjusted, and the adjustment amount is the difference between the theoretical deposition rate and the measured deposition rate; If the measured deposition rate and scanning speed deviate from the theoretical values, the deposition rate and scanning speed are adjusted synchronously. For thicker areas, the deposition rate and scanning speed are proportionally reduced; for thinner areas, the deposition rate and scanning speed are proportionally increased.

10. An optical thin film deposition scanning control system, characterized in that: Region division and uniformity judgment module: divides the optical film into several regions and determines whether the thickness of the optical film is uniform; Abnormal thickness area classification module: If the thickness of the optical film is uneven, each area is divided into thicker areas and thinner areas, and a set of thicker areas and a set of thinner areas are generated; Deposition parameter matching analysis module: calculates the matching degree between the deposition rate and scanning speed of the equipment, and determines whether the deposition rate and scanning speed match; Non-uniformity cause correlation verification module: If there is a mismatch, the deposition rate and scanning speed of the thicker and thinner areas are analyzed to determine whether the optical film non-uniformity is caused by the mismatch between the deposition rate and scanning speed; Deposition parameter coordinated adjustment module: If the uneven thickness of the optical film is caused by the mismatch between the deposition rate and the scanning speed, the deposition rate and the scanning speed are adjusted according to the theoretical relationship between the thickness of the optical film and the deposition rate and the scanning speed.

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