Metal mask and method of manufacturing the same

Abstract

The application provides a metal mask plate and a manufacturing method thereof. The manufacturing method of the metal mask plate comprises the following steps: determining a length deviation variation and a wave shape variation of a base material based on a length deviation value and a wave shape value of a plurality of partitions of the base material; creating a correlation model for representing a correlation relationship among the length deviation variation, the wave shape variation and a pixel hole variation of the base material; substituting the length deviation variation and the wave shape variation of the base material into the correlation model to obtain a predicted value of the pixel hole variation of the base material; and adjusting a manufacturing process of the metal mask plate when the predicted value of the pixel hole variation of the base material is not less than a target threshold value. The application predicts the predicted value of the pixel hole variation of the metal mask plate before manufacturing the metal mask plate, adjusts the standard manufacturing process according to the predicted value, and makes the pixel hole variation of the metal mask plate manufactured based on the adjusted manufacturing process meet the design requirements, thereby improving the product consistency.

Description

Metal mask plate and its manufacturing method Technical Field

[0001] This invention relates to the field of metal photomask technology, and more specifically, to a metal photomask and its manufacturing method. Background Technology

[0002] In the metal photomask manufacturing industry, TP (Total Pitch) is one of the important performance control indicators. It quantifies the global positional accuracy of the photomask pattern. The TP value includes the pixel hole deviation value, which is represented by TPX and is closely related to the product yield in the process of manufacturing metal photomasks.

[0003] Specifically, a metal mask has a pixel hole array used to fabricate a pixel array on a substrate, and the pixel hole array is regular. However, metal masks with pixel hole arrays of the same design may be made from various base materials. Due to the inconsistency in the plate shape of the base materials, the pixel hole array precision of metal masks made from different base materials varies. This manifests as the pixel hole array on some metal masks not being regular in shape, for example, there are positional deviations between pixel holes in the same column but not in the same row.

[0004] For example, as shown in Figure 1, a single metal mask has multiple pixel holes arranged in an array: A1~A9, B1~B9, C1~C9. A1~A9 form a row of pixel holes, A1, B1, and C1 form a column of pixel holes, and so on. A coordinate system is established using the metal mask itself. The length direction of the metal mask is the X-axis, i.e., the row direction of the pixel holes, and the width direction of the metal mask is the Y-axis, i.e., the column direction of the pixel holes. The distance between the center points of A1 and A9 is d1, the distance between the center points of B1 and B9 is d2, and the distance between the center points of C1 and C9 is d3. In the design, d1=d2=d3.

[0005] However, due to deviations in the base material shape, the values ​​of d1, d2, and d3 in the same metal mask will vary. Therefore, the average spacing between pixel holes in different rows on the X-axis is called the pixel hole deviation value, denoted by TPX. TPX is specifically equal to the average of d1, d2, and d3. The maximum difference in TPX among metal masks manufactured from the same base material is the pixel hole variation, denoted by TPX Gap.

[0006] Currently, the TPX Gap value cannot be predicted before the metal mask is manufactured. It can only be measured after the pixel holes of the metal mask are manufactured. Then it is determined whether the TPX Gap meets the design deviation. If it does not meet the design standard, the metal mask does not meet the design standard and must be scrapped. This leads to a great waste of materials and manufacturing costs. Summary of the Invention

[0007] This application provides a metal mask and its manufacturing method to solve the technical problem that the TPX Gap value cannot be predicted before the metal mask is manufactured, which can easily lead to material waste or manufacturing cost waste.

[0008] In a first aspect, this application provides a method for manufacturing a metal photomask, comprising:

[0009] Based on the length deviation and waviness values ​​of multiple zones of the base material, the changes in length deviation and waviness of the base material are determined respectively; the length deviation value is used to characterize the degree of difference between the actual length and axial length of the zone, and the waviness value is used to characterize the degree of undulation of the zone.

[0010] Create an association model to characterize the relationship between the length deviation, waviness variation, and pixel hole variation of the base material; multiple metal masks are made from the same base material, and each metal mask includes multiple pixel holes arranged in an array. In multiple rows of pixel holes, the average distance between the centers of the pixel holes at both ends of the same row is the pixel hole deviation value. Among the pixel hole deviation values ​​of multiple metal masks, the difference between the maximum and minimum values ​​is the pixel hole variation.

[0011] Substitute the changes in length deviation and waviness of the base material into the correlation model to obtain the predicted value of the pixel hole change of the base material.

[0012] If the predicted value of the pixel hole variation in the base material is not less than the target threshold, adjust the manufacturing process of the metal mask.

[0013] In some embodiments, a correlation model is created to characterize the relationship between changes in the length deviation of the base material, changes in waviness, and changes in pixel aperture, including:

[0014] The test master roll was divided into multiple master material samples, and annealing tension tests were performed on each master material sample to measure the change in length deviation and waviness of each master material sample. The annealing conditions were different for each master material sample during the test.

[0015] Based on standard manufacturing processes, each base material sample is manufactured to produce multiple metal mask plate samples distributed along the width direction. The pixel hole deviation value of a single metal mask plate sample is measured to determine the pixel hole variation of each base material sample. The length deviation variation, waviness variation, and pixel hole variation of multiple base material samples form multiple sets of sample data pairs.

[0016] By fitting multiple sets of sample data, a correlation model is obtained to characterize the relationship between the changes in length deviation, waviness, and pixel hole size of the parent material sample.

[0017] In some embodiments, multiple sets of sample data are fitted to obtain a correlation model that characterizes the relationship between the length deviation, waviness variation, and pixel aperture variation of the parent material sample, including:

[0018] By fitting multiple sets of sample data, the following relationship is obtained:

[0019] ;

[0020] Based on the parent material, the design compensation value b is determined, and the correlation model is obtained:

[0021] ;

[0022] in, This represents the absolute value of the pixel aperture change. This represents the change in length deviation. For wave shape variation, =15.2, =0.141.

[0023] In some embodiments, the metal mask sample was measured. The value obtained by subtracting the expression The value of b is obtained by taking the value of b.

[0024] In some embodiments, fitting multiple sets of sample data pairs yields a correlation model characterizing the relationship between changes in length deviation, waviness, and pixel aperture of the parent material sample, and further includes:

[0025] By fitting multiple sets of sample data pairs, a correlation model is obtained to characterize the relationship between the length deviation, waviness, and pixel hole changes of the base material sample. Based on the sample data of multiple base material samples and the corresponding exposure and / or etching tension during annealing tests of multiple base material samples, the correlation between the pixel hole changes of the base material sample and the exposure and / or etching tension is determined.

[0026] In some embodiments, when the predicted value of the pixel aperture change in the parent material is not less than a target threshold, the manufacturing process of the metal mask is adjusted, including:

[0027] When the predicted value of the pixel aperture variation in the base material is less than 5 micrometers, a metal mask is manufactured based on standard manufacturing processes.

[0028] If the predicted value of the pixel aperture variation in the base material is not less than 5 micrometers, adjust the tension applied to the base material during exposure and / or etching in the manufacturing process of the metal mask.

[0029] In some embodiments, when the predicted value of the pixel aperture variation in the base material is not less than 5 micrometers, adjusting the tension applied to the base material during exposure and / or etching in the manufacturing process of the metal mask includes:

[0030] When the waviness variation is not less than 100 micrometers, increase the tension applied to the base material during the exposure process in the manufacturing process of the metal mask;

[0031] With a length deviation of not less than 0.2 micrometers, reduce the tension applied to the base material during the etching process in the manufacturing process of the metal mask.

[0032] In some embodiments, the changes in length deviation and waviness of the base material are determined based on the length deviation values ​​and waviness values ​​of multiple zones of the base material, including:

[0033] Determine the effective area of ​​the base material, divide the effective area into multiple partitions along the width direction, and obtain the length deviation value and waviness value of each partition; the number of partitions corresponds to the number of metal mask plates made from the effective area.

[0034] Among the maximum length deviation values ​​of multiple zones, the difference between the maximum and minimum values ​​is the change in length deviation of the base material. Among the average values ​​of the waviness values ​​of multiple zones, the difference between the maximum and minimum values ​​is the change in waviness of the base material.

[0035] In some embodiments, the partition has multiple line units distributed along the width direction, and the length deviation value of the partition includes the length deviation value of each of the multiple line units; the length deviation value of each line unit is... , The actual length per line unit. The axial length in line units;

[0036] The wave value of a zone includes the wave value of each line unit. The wave value of a line unit is the ratio of the wave height to the wavelength of the line unit.

[0037] In a second aspect, this application provides a metal mask, manufactured by any of the manufacturing methods provided in the first aspect above, comprising: a plurality of pixel holes arranged in an array.

[0038] The metal photomask and its manufacturing method provided in this application have the following technical advantages:

[0039] By predicting the pixel aperture variation of the metal mask before manufacturing, and adjusting the standard manufacturing process of the metal mask based on the predicted pixel aperture variation, the pixel aperture variation of the metal mask manufactured based on the adjusted manufacturing process meets the design requirements. This can improve product consistency, increase product yield, and reduce waste of materials and manufacturing costs. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments of the present invention will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 is a schematic diagram of the structure of a metal mask plate provided in an embodiment of this application;

[0042] Figure 2 is a schematic flowchart of a method for manufacturing a metal mask plate according to an embodiment of this application;

[0043] Figure 3 is one of the structural schematic diagrams of the base material in a method for manufacturing a metal mask plate according to an embodiment of this application;

[0044] Figure 4 is a second schematic diagram of the structure of the base material in a method for manufacturing a metal mask plate according to an embodiment of this application.

[0045] Figure label:

[0046] 100 - Main material; 110 - First zone; 120 - Second zone; 130 - Line unit;

[0047] 200 - Metal mask; 210 - Pixel hole. Detailed Implementation

[0048] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.

[0049] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in this application's specification means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude implementations of other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by this art. It should be understood that when we say an element is "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element, or it may mean that the element and the other element are connected through an intermediate element. Furthermore, "connected" or "coupled" as used herein may include wireless connections or wireless coupling. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" may be implemented as "A," or as "B," or as "A and B."

[0050] First, let me explain the terms used in this application:

[0051] Master roll: The original, complete roll of material that has come off the production line and has not yet undergone any slitting or cutting process.

[0052] Base material: obtained by slitting the master roll, and used as the raw material for manufacturing metal photomasks.

[0053] Length deviation value: IU (an international unit, abbreviated as I-Unit), defined as a quantitative index of the relative length difference in the width direction of the base material, reflecting the uniformity of residual stress distribution within the base material. Quantification method: 1IU = That is, for every 100,000 units of length, there is a difference of 1 unit of length. The smaller the IU value, the smaller the difference between the axial length and the actual length of the base material, and the flatter the base material.

[0054] Wave value: Wave is defined as the visible wave-like undulations exhibited by the base material due to uneven internal stress. It is a direct manifestation of the external macroscopic morphology caused by uneven internal stress. Quantification method: It is usually measured by the ratio of wave height to wavelength. The smaller the ratio, the lower the degree of undulation and the more slight the wave.

[0055] For ease of description, the change in length deviation determined based on the length deviation value is referred to as... This indicates that the wave change determined based on the wave value is used... The pixel aperture deviation value is represented by TPX, and the pixel aperture variation determined based on the pixel aperture deviation value is represented by TPX. express.

[0056] The research and development approach of this application includes addressing the issue that inconsistencies in the substrate material shape lead to differences in the pixel hole array precision of metal photomasks manufactured from different substrate materials. Specifically, some substrate materials exhibit uneven stress distribution and irregular, wavy shapes (as shown in Figure 3), while others have better flatness. This results in the inability to obtain equally regular pixel hole arrays from substrate materials of different shapes using the same standard manufacturing process and to manufacture the same pixel hole array, leading to poor product consistency and low yield.

[0057] The research and development approach of this application also includes: the profile data of the base material can be quantified using the length deviation value (IU) and the waviness value (Wave). The profile data of the base material before manufacturing the metal mask is related to the TPX Gap of the manufactured metal mask. Therefore, by predicting the TPX Gap of the metal mask before its manufacturing, this application can determine in advance whether the metal mask manufactured from the base material meets the design requirements.

[0058] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0059] This application provides a method for manufacturing a metal mask 200. A flowchart of this method is shown in Figure 2. The method includes steps S1-S4:

[0060] S1: Based on the length deviation values ​​IU and wave value Wave of multiple zones of the base material 100, determine the change in length deviation of the base material 100. Wave shape change The length deviation value IU is used to characterize the degree of difference between the actual length and the axial length of each partition, and the wave value Wave is used to characterize the degree of undulation of each partition.

[0061] S2: Create a characterization of the length deviation change of the base material 100. Wave shape change and pixel hole variation The correlation model of the relationship between them; multiple metal masks 200 are made from the same base material 100, and each metal mask 200 includes multiple pixel holes 210 arranged in an array. Among the multiple rows of pixel holes 210, the average distance between the centers of the pixel holes 210 at both ends of the same row is the pixel hole deviation value TPX. Among the pixel hole deviation values ​​TPX of multiple metal masks 200, the difference between the maximum and minimum values ​​is the pixel hole change amount TPX Gap.

[0062] S3: The change in length deviation of the base material 100 Wave shape change Substitute the values ​​into the correlation model to obtain the predicted value of the pixel hole change TPX Gap of the base material 100.

[0063] S4: If the predicted value of the pixel hole variation TPX Gap of the parent material 100 is not less than the target threshold, adjust the manufacturing process of the metal mask 200.

[0064] In this embodiment, by predicting the value of the pixel aperture variation TPX Gap of the metal mask 200 before manufacturing the metal mask 200, the standard manufacturing process of the metal mask 200 is adjusted according to the predicted value of the pixel aperture variation TPX Gap, so that the pixel aperture variation TPX Gap of the metal mask 200 manufactured based on the adjusted manufacturing process meets the design requirements. This can improve product consistency, increase product yield, and reduce waste of materials and manufacturing costs.

[0065] Specifically, the change in length deviation of the base material 100 Wave shape change There is a correlation between the pixel aperture change and the TPX Gap, which can be used to pre-create a characterization of the length deviation change of the base material 100. Wave shape change A correlation model was established to establish the relationship between pixel aperture variation TPX Gap. Before manufacturing the metal mask 200, the length deviation value IU and waviness value Wave of the base material 100 were obtained, and the length deviation variation was calculated accordingly. Wave shape change Then, the change in length deviation of the base material 100 is... Wave shape change By substituting the values ​​into the correlation model, the predicted value of the pixel aperture change TPX Gap can be obtained. Then, by judging the relationship between the predicted value of the pixel aperture change TPX Gap and the target threshold, it can be determined whether the standard manufacturing process of the metal mask 200 needs to be adjusted.

[0066] The manufacturing method of this application will be described in detail below.

[0067] In some embodiments, the length deviation value IU and waviness value Wave of the parent material 100 in step S1 above are used to determine the change in length deviation of the parent material 100, respectively. Wave shape change It includes the following steps:

[0068] The effective area of ​​the base material 100 is determined, and the effective area is divided into multiple partitions along the width direction. The length deviation value IU and the waviness value Wave of each partition are obtained. The number of partitions corresponds to the number of metal mask plates 200 made from the effective area.

[0069] Among the maximum length deviation values ​​determined for each of the multiple partitions, the difference between the maximum and minimum values ​​is the length deviation change of the base material by 100. The difference between the maximum and minimum values ​​of the wave values ​​(Wave) of multiple zones is determined as the wave variation of the base material (100). .

[0070] In this step, the effective area of ​​the base material 100 is the area ultimately used to manufacture the metal mask 200. The edge areas outside the effective area have poor shape and will be cut off after the metal mask 200 is manufactured. The effective area is relatively wide along the width direction, and multiple metal masks 200 will eventually be manufactured along the width direction. As shown in Figure 4, in this embodiment, the effective area is divided into multiple partitions along the width direction. The number of partitions corresponds to the number of metal masks 200 ultimately manufactured, and the area where the partition is located in the effective area corresponds one-to-one with the area of ​​the metal mask 200 ultimately manufactured from the effective area.

[0071] Next, we will explain in detail how IU and Wave are calculated.

[0072] In some embodiments, as shown in FIG4, each partition has multiple line units 130 distributed along the width direction, and the length deviation value IU of the partition includes the length deviation value IU of each of the multiple line units 130; the IU of each line unit 130 is... , The actual length of the line unit is 130. The axial length is 130 for the line unit.

[0073] In this embodiment, a coordinate system can be established for each parent material 100. Each parent material 100 has a reference plane, with the length direction of the reference plane being the X-axis and the direction perpendicular to the reference plane being the Z-axis. The initial X-axis coordinate of the parent material 100 is 0. Multiple line units 130 distributed along the width direction are selected within each partition. Each line unit 130 can be referred to as a line IU, and IU can be considered as one unit. ,but, This refers to the actual length of an IU, that is, the actual length of the undulating IU. Let IU be the axial length of the IU, i.e., the X-coordinate value of the IU. The specific value of each IU can be calculated using the IU calculation formula, thus obtaining the specific values ​​of multiple IUs within each partition. Then, the largest IU is selected as the [value]. Then, the overall 100 of the parent material is calculated. .

[0074] In addition, the wave value Wave of the partition includes the Wave of each of the multiple line units 130. The wave value Wave of line unit 130 is the ratio of the wave height to the wavelength of line unit 130.

[0075] In this embodiment, within each partition, one IU corresponds to one Wave. Wave is the ratio of the wave height to the wavelength of the IU. The wave height is the Z-axis coordinate value of the highest or lowest point within each IU. Since Z-axis coordinate values ​​can be positive or negative, the absolute value is taken. The wavelength is the X-axis coordinate value of each IU. Each partition also includes multiple Waves. The average value Ave(Wave) of multiple Waves within each partition is taken, and then the overall matrix 100 is calculated. .

[0076] Optionally, the IU and Wave values ​​in this application are the IU and Wave values ​​of the base material after 100% annealing.

[0077] Therefore, in this embodiment, each partition has multiple IUs, and the maximum length deviation value in each partition is determined to be Max(IU). The maximum length deviation values ​​for the multiple partitions are then as follows: Among them, the largest maximum length deviation is The smallest maximum length deviation value is

[0078] ,but:

[0079]

[0080] Each partition has multiple Waves. If the average wave value in each partition is determined to be Ave(Wave), then the average wave values ​​for the multiple partitions are as follows: The largest average wave value is The smallest average wave value is ,but:

[0081]

[0082] A coordinate system is established using the base material 100, with the length direction as the X-axis and the width direction as the Y-axis. Multiple metal masks 200 are fabricated from the same base material 100 along the Y-axis. Each metal mask 200 includes multiple pixel holes 210 arranged in an array, with the X-axis representing the row direction of the pixel holes 210 and the Y-axis representing the column direction. In each row of pixel holes 210, the distance between the center of the first pixel hole 210 and the center of the last pixel hole 210 is the difference between the X-axis coordinates of the center points of the two pixel holes 210. The average value of this difference across multiple rows of pixel holes 210 is the pixel hole deviation value TPX. The pixel hole deviation values ​​of the multiple metal masks 200 include: ,but:

[0083]

[0084] In this embodiment, the IU of each partition is calculated to determine the overall matrix 100. , so that the obtained It is more holistic and comprehensive, and can more accurately match the pixel aperture variation of the final manufactured metal mask 200. The predicted value can thus reduce the pixel hole variation caused by the large difference in plate shape along the width direction of the base material 100. This reduces the risk of significant discrepancies between predicted and actual values ​​and can improve the accuracy of predictions.

[0085] Optionally, the base material 100 is rectangular, having two long sides and two short sides, with the effective area referring to the region of the base material 100 at least 15 mm away from the long side.

[0086] In some embodiments, the creation of the correlation model in step S2 above, used to characterize the relationship between the length deviation, waviness variation, and pixel hole variation of the base material 100, includes the following steps:

[0087] The test master roll was divided into multiple master material samples, and annealing tension tests were performed on each master material sample to measure the change in length deviation for each master material sample. Wave shape change The annealing conditions were different for each sample of the base material.

[0088] Based on standard manufacturing processes, multiple metal mask samples distributed along the width direction are manufactured from each parent material sample. The pixel hole deviation value of a single metal mask sample is measured. Determine the pixel aperture variation for each parent material sample. ; Length deviation variation of multiple parent material samples Wave shape change Pixel aperture variation Multiple sets of sample data pairs are formed.

[0089] The multiple sets of sample data are fitted to obtain the amount of length deviation change used to characterize the parent material sample. Wave shape change and pixel hole variation A correlation model of the relationships between them.

[0090] In this embodiment, multiple base material samples with identical plate shape data are annealed under different conditions. Before annealing, the base material 100 is extremely unstable and filled with residual stress. Annealing, through recrystallization and stress release, brings the material to a more stable and uniform new state. Then, the properties of each annealed base material 100 are measured. , In other words, this embodiment collects the trend of plate shape change under different tension conditions before and after annealing by conducting segmented annealing tension tests on the test master roll.

[0091] It is understandable that each metal mask 200 design corresponds to a standard manufacturing process, in which the parameters of each process step are fixed. However, due to the inconsistent plate shape of the base material 100, the precision of metal mask 200 manufactured using the same standard manufacturing process is inconsistent. In this embodiment, one test master roll can obtain multiple base material samples. Assuming that the base material samples from the same test master roll have the same plate shape data but different annealing conditions, multiple sets of sample data pairs are obtained by testing multiple base material samples. Each set of sample data pairs includes one base material sample. , Data, by fitting multiple sets of sample data pairs to obtain a correlation model, can characterize the parent material samples. , The relationship between the three variables.

[0092] Optionally, the annealing conditions for the base material sample test include: temperature conditions, tension conditions, and linear velocity conditions. By setting different annealing conditions, annealing experiments are conducted on different base materials 100 to obtain multiple sets of data pairs.

[0093] For example, the temperature conditions include three parameters: 550℃, 600℃, and 650℃; the tension conditions include five parameters: 500N, 1000N, 1200N, 1600N, and 2000N; and the linear speed conditions (or holding time) include five parameters: 5min, 7min, 10min, 20min, and 30min. By arranging and combining the above conditions, more than 50 annealing conditions are obtained. The test master roll is cut into 50 sheets of base material 100, and annealing tests are carried out under 50 different annealing conditions to obtain 50 sets of data pairs.

[0094] In some embodiments, the above steps of fitting multiple sets of sample data pairs to obtain a correlation model for characterizing the relationship between the length deviation, waviness variation, and pixel aperture variation of the parent material sample include the following specific steps for creating the model:

[0095] By fitting multiple sets of sample data, the relation (1) is obtained:

[0096] (1)

[0097] Based on the parent material 100, the design compensation value b is determined, and the correlation model (2) is obtained:

[0098] (2)

[0099] in, Take the absolute value. This represents the change in length deviation. For wave shape variation, =15.2, =0.141.

[0100] In this embodiment, the sample data pairs are first fitted to obtain the relation (1); by judging the plate type data of the parent material 100, the design compensation value b is determined to obtain the correlation model (2); wherein, the model obtained based on the relation (1) is... Since the value is relatively large, a compensation value b is used to compensate the relation (1) to obtain the association model (2), so that the association model (2) obtained is more efficient. The value compared to that obtained based on relation (1) The value was reduced by the design compensation value b, thus making the result obtained based on the correlation model (2) The value is small, approaching 0. Then, by making small adjustments to the manufacturing process, the actual production... Approaching 0 ensures product consistency and accuracy.

[0101] Optionally, during the fitting process, relation (1) is obtained, confirming... , same Strong negative correlation, specifically reflected in the coefficient of determination. Satisfies 0.91 0.95, the coefficient of determination A value greater than 0.85 indicates that the relationship has a good fit and the prediction results are relatively accurate.

[0102] Furthermore, based on the average TPX Gap level predicted from the multiple test master rolls in stock, the b-value can be defined for selection. For example, the b-value can be divided into different levels, such as 10 micrometers, 20 micrometers, 30 micrometers, etc. The b-value design compensates for the larger value of the TPX Gap of the original master material 100, taking an integer value. After subtracting the b-value from the fitted relationship (1), it can be fine-tuned using process parameters. This embodiment designs different b-values ​​for different test master rolls, which is highly targeted. In the subsequent process adjustment, only the manufacturing process needs to be fine-tuned, which is highly feasible. There is no need to make large-scale adjustments to the process, avoiding the situation where the process cost surges or even cannot be achieved due to large-scale adjustments to the process.

[0103] In some embodiments, the metal mask sample was measured. The value of is obtained by subtracting the value obtained in relation (1). The value of b is obtained by taking the value of b.

[0104] In this embodiment, the actual measurement of the metal mask plate sample is performed. The value of is obtained by subtracting the value obtained in relation (1). The value of b is obtained to determine the design compensation value b of the parent material sample corresponding to the metal mask plate sample, and then the design compensation value b of the same type of test master roll can be determined.

[0105] In some embodiments, the b value is an integer. Since there are many types of base material 100, using an integer b value allows various base materials 100 with different but similar board types to be grouped into the same category, and the same b value to create an association model.

[0106] In some embodiments, multiple sets of sample data are fitted to obtain the amount of length deviation change used to characterize the parent material sample. Wave shape change The correlation model for the relationship between pixel aperture variation TPX Gap also includes:

[0107] By fitting multiple sets of sample data, the amount of length deviation change used to characterize the sample of the parent material is obtained. Wave shape change A correlation model was developed to establish the relationship between the pixel aperture change TPX Gap and the annealing tension, based on sample data from multiple base material samples and the corresponding exposure and / or etching tension during annealing tests with multiple base material samples.

[0108] In this embodiment, the base material sample is first annealed during the test, and then a metal mask 200 is manufactured through exposure and etching processes. The obtained multiple sets of data can also determine the correlation between the pixel hole change TPX Gap of the base material sample and the exposure and / or etching tension. In the subsequent process adjustment, the exposure tension and etching tension are adjusted according to the TPX Gap so that the TPX Gap of the final metal mask 200 can approach 0.

[0109] Next, after creating the association model (2), step S3 is executed to transfer the pre-obtained parent material 100... , Substituting into the correlation model (2), the value of TPX Gap can be obtained, which is the predicted value of the pixel hole change of the parent material 100.

[0110] In some embodiments, adjusting the manufacturing process of the metal mask 200 in step S4 above, where the predicted value of the pixel hole variation in the parent material 100 is not less than the target threshold, includes the following steps:

[0111] When the predicted value of the pixel hole variation in the base material 100 is less than 5 micrometers, the metal mask 200 is manufactured based on the standard manufacturing process.

[0112] If the predicted value of the pixel aperture variation of the base material 100 is not less than 5 micrometers, adjust the tension applied to the base material 100 during the exposure and / or etching process in the manufacturing process of the metal mask 200.

[0113] In this embodiment, after step S3, a judgment operation is performed to determine the difference between the predicted value of TPX Gap obtained in S3 and the target threshold of 5 micrometers. If the predicted value of TPX Gap is less than 5 micrometers, it indicates that the shape of the parent material 100 is good, the error of the manufactured metal mask 200 is within a controllable range, and the accuracy is good. No adjustment of the manufacturing process is required, and the metal mask 200 can be manufactured using the standard manufacturing process. If the predicted value of TPX Gap is equal to or greater than 5 micrometers, it indicates that the shape of the parent material 100 is poor, the error of the manufactured metal mask 200 is large, and the accuracy is poor. The manufacturing process needs to be adjusted, and the metal mask 200 is manufactured using the adjusted manufacturing process to ensure that the accuracy of the manufactured metal mask 200 is good and meets the design requirements.

[0114] Specifically, the fabrication of the metal mask 200 requires exposure and etching processes. During these processes, a certain amount of tension needs to be applied to the substrate 100 to facilitate the fabrication of the mask. In the process of creating the correlation model (2), the correlation between the pixel hole variation TPX Gap of the substrate sample and the exposure tension and etching tension can be determined. Therefore, in this embodiment, by increasing or decreasing the tension applied to the substrate 100 during the exposure and / or etching processes in the fabrication of the metal mask 200, the fabrication process of the metal mask 200 can be compensated, resulting in a metal mask 200 with better precision.

[0115] After adjusting the manufacturing process parameters of the metal mask 200 and verifying the TPX gap capability window, the following can be obtained:

[0116] ①In When the tension applied to the substrate during exposure is greater than 100 micrometers, the TPX Gap coefficient is strongly linearly affected by the tension of 100 N: 1 N tension affects the TPX Gap by 0.5 micrometers; as the exposure tension increases, the TPX Gap decreases.

[0117] ②In When the tension applied to the substrate during etching is greater than 0.3 micrometers, the TPX Gap coefficient is strongly linearly affected by the 100 N tension applied during etching: the TPX Gap changes by 1.5 micrometers with 1 N tension; as the etching tension increases, the TPX Gap decreases.

[0118] Therefore, this application also provides a method for adjusting a manufacturing process, wherein, in the above steps, when the predicted value of the pixel hole variation of the base material 100 is not less than 5 micrometers, the tension applied to the base material 100 during the exposure and / or etching process in the manufacturing process of the metal mask 200 is adjusted, including the following steps:

[0119] When the waviness variation is not less than 100 micrometers, increase the tension applied to the base material 100 during the exposure process in the manufacturing process of the metal mask 200.

[0120] With a length deviation of not less than 0.2 micrometers, reduce the tension applied to the base material 100 during the etching process in the manufacturing process of the metal mask 200.

[0121] In this embodiment, increasing the exposure tension can reduce the TPX gap, and decreasing the etching tension can also reduce the TPX gap, thereby reducing the final TPX gap and meeting the design requirements.

[0122] The following explanation uses specific experimental data to illustrate the method for adjusting the manufacturing process of the metal mask 200 of this application.

[0123] Taking a base material 100 as an example, the base material 100 is divided into a first section 110 and a second section 120. 14 line units 130 are taken from each section. The measured IU and Wave of the base material 100 are shown in Table 1.

[0124]

[0125] Table 1. IU and Wave values ​​of base material 100

[0126] Among them, Item refers to the number of lines in line unit 130. Items 1-14 belong to the first partition 110, Items 3-14 belong to the valid area of ​​the first partition 110, Items 15-28 belong to the second partition 120, and Items 15-26 belong to the valid area of ​​the second partition 120.

[0127] Calculate the IU and Wave values ​​in the table above:

[0128] The largest IU value in the first partition (110) is 0.54, and the largest IU value in the second partition (120) is 0.24. Therefore, =0.54-0.24=0.3.

[0129] The average wave value within the first partition (110) is 190, and the average wave value within the second partition (120) is 310. Therefore, .

[0130] Will Substituting into the correlation model (2), b is 0, resulting in TPX Gap = -21.48. The absolute value is 21.48, which is greater than the target threshold of 5, indicating that the manufacturing process needs to be adjusted.

[0131] Therefore, judgment If the value is greater than 0.2, the etching tension will be reduced from 100N to 92N, a decrease of 8%, resulting in an expected reduction of 12 micrometers in the TPX gap; [This is followed by a seemingly unrelated sentence about judgment / determination.] If the value is greater than 100, the exposure tension will be increased from 100N to 120N, making the final TPX Gap approach 0.

[0132] Since the percentage decrease in etching tension is 0.9 times the percentage increase in adjustment time, the etching time increases. To ensure that the etching size maintains the target value, the exposure aperture size needs to be reduced accordingly.

[0133] Therefore, reducing the etching tension by 8% requires increasing the etching time by 7% and simultaneously increasing the exposure energy by 10%.

[0134] Based on the same inventive concept, this application provides a metal mask 200, which is manufactured by any of the manufacturing methods provided in the above embodiments. As shown in FIG1, the metal mask 200 includes a plurality of pixel holes 210 arranged in an array.

[0135] In this embodiment, the metal mask 200 is manufactured using any of the manufacturing methods provided in the aforementioned embodiments. The underlying principle is similar and will not be repeated here. Among the multiple metal masks 200 manufactured in this embodiment, the TPX Gap value is less than 5 micrometers, approaching 0, which meets the design requirements, resulting in good product consistency and a higher yield.

[0136] By applying the embodiments of this application, at least the following beneficial effects can be achieved:

[0137] 1. By predicting the pixel aperture variation of the metal mask 200 before manufacturing, the standard manufacturing process of the metal mask 200 is adjusted according to the predicted pixel aperture variation. This ensures that the pixel aperture variation of the metal mask 200 manufactured based on the adjusted manufacturing process meets the design requirements, thereby improving product consistency, increasing product yield, and reducing waste of materials and manufacturing costs.

[0138] 2. In this embodiment, the IU of the entire base material 100 is determined by calculating the IU of each partition. , so that the obtained It is more holistic and comprehensive, and can more accurately match the pixel aperture variation of the final manufactured metal mask 200. The predicted value can thus reduce the pixel hole variation caused by the large difference in plate shape along the width direction of the base material 100. This reduces the risk of significant discrepancies between predicted and actual values ​​and can improve the accuracy of predictions.

[0139] 3. A single test master roll can yield multiple base material samples. Assuming the base material samples from the same test master roll have the same sheet shape data but different annealing conditions; by testing multiple base material samples, multiple sets of sample data pairs are obtained. Each set of sample data pairs includes data from one base material sample. , Data, by fitting multiple sets of sample data pairs to obtain a correlation model, can characterize the parent material samples. , The correlation between the three variables lays the foundation for predicting the TPX Gap value.

[0140] 4. This embodiment designs different b values ​​for different test master rolls, which is highly targeted. In the subsequent process of adjusting the process, only minor adjustments to the manufacturing process are needed, which is highly feasible and does not require major process adjustments. This avoids the situation where the process cost surges or even becomes impossible due to major process adjustments.

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for manufacturing a metal photomask, characterized in that, include: Based on the length deviation value and waviness value of multiple partitions of the base material, the length deviation change and waviness change of the base material are determined respectively, including: determining the effective area of ​​the base material, dividing the effective area into multiple partitions along the width direction, and obtaining the length deviation value and waviness value of each of the multiple partitions; The number of partitions corresponds to the number of metal masks made from the effective area; the difference between the maximum and minimum values ​​of the maximum length deviation values ​​of each of the partitions is determined as the length deviation change of the base material; the difference between the maximum and minimum values ​​of the average waviness values ​​of each of the partitions is determined as the waviness change of the base material; the length deviation value is used to characterize the degree of difference between the actual length and axial length of the partition, and the waviness value is used to characterize the degree of undulation of the partition; a correlation is created to characterize the relationship between the length deviation change, waviness change, and pixel aperture change of the base material. The model is used to fabricate multiple metal masks from the same base material. Each metal mask includes multiple pixel holes arranged in an array. In multiple rows of pixel holes, the average distance between the centers of the pixel holes at both ends of the same row is the pixel hole deviation value. Among the pixel hole deviation values ​​of multiple metal masks, the difference between the maximum and minimum values ​​is the pixel hole variation. The length deviation variation and waviness variation of the base material are substituted into the correlation model to obtain the predicted value of the pixel hole variation of the base material. If the predicted value of the pixel hole variation of the base material is not less than the target threshold, the manufacturing process of the metal mask is adjusted.

2. The manufacturing method according to claim 1, characterized in that, Creating a correlation model to characterize the relationship between the length deviation, waviness variation, and pixel hole variation of the base material includes: dividing the test master roll into multiple base material samples; conducting annealing tension tests on each of the multiple base material samples; measuring the length deviation and waviness variation of each base material sample; the annealing conditions for each base material sample are different; based on standard manufacturing processes, manufacturing multiple metal mask plate samples distributed along the width direction for each base material sample; measuring the pixel hole deviation value of a single metal mask plate sample; determining the pixel hole variation of each base material sample; forming multiple sets of sample data pairs based on the length deviation, waviness variation, and pixel hole variation of multiple base material samples; and fitting the multiple sets of sample data pairs to obtain a correlation model characterizing the relationship between the length deviation, waviness variation, and pixel hole variation of the base material samples.

3. The manufacturing method according to claim 2, characterized in that, Fitting the multiple sets of sample data pairs to obtain a correlation model characterizing the relationship between the length deviation, waviness variation, and pixel hole variation of the parent material sample includes: fitting the multiple sets of sample data pairs to obtain the following relationship: Based on the parent material, the design compensation value b is determined, and the correlation model is obtained: ;in, This represents the absolute value of the pixel aperture change. This represents the change in length deviation. For wave shape variation, =15.2， =0.141。 4. The manufacturing method according to claim 3, characterized in that, The metal mask sample was measured. The value obtained by subtracting the relation from the value obtained The value of b is obtained by taking the value of b.

5. The manufacturing method according to claim 2, characterized in that, Fitting the multiple sets of sample data pairs to obtain a correlation model that characterizes the relationship between the length deviation change, waviness change, and pixel hole change of the base material sample, further includes: fitting the multiple sets of sample data pairs to obtain a correlation model that characterizes the relationship between the length deviation change, waviness change, and pixel hole change of the base material sample; and determining the correlation between the pixel hole change of the base material sample and the exposure and / or etching tension corresponding to the annealing test of the multiple base material samples based on the sample data pairs of the multiple base material samples.

6. The manufacturing method according to claim 1, characterized in that, If the predicted value of the pixel aperture variation in the base material is not less than the target threshold, the manufacturing process of the metal mask is adjusted, including: if the predicted value of the pixel aperture variation in the base material is less than 5 micrometers, the metal mask is manufactured based on a standard manufacturing process; if the predicted value of the pixel aperture variation in the base material is not less than 5 micrometers, the tension applied to the base material during the exposure and / or etching process in the manufacturing process of the metal mask is adjusted.

7. The manufacturing method according to claim 6, characterized in that, When the predicted value of the pixel aperture variation in the base material is not less than 5 micrometers, the tension applied to the base material during the exposure and / or etching process in the manufacturing process of the metal mask is adjusted, including: when the waviness variation is not less than 100 micrometers, increasing the tension applied to the base material during the exposure process in the manufacturing process of the metal mask; and when the length deviation variation is not less than 0.2 micrometers, decreasing the tension applied to the base material during the etching process in the manufacturing process of the metal mask.

8. The manufacturing method according to claim 1, characterized in that, The partition has multiple line units distributed along its width, and the length deviation value of the partition includes the length deviation value of each of the multiple line units; the length deviation value of each line unit is... ， The actual length of the line unit. The axial length of the line unit; the waviness value of the partition includes the waviness value of each of the line units, and the waviness value of the line unit is the ratio of the wave height to the wavelength of the line unit.

9. A metal mask, characterized in that, The product is manufactured by the manufacturing method according to any one of claims 1-8, comprising: a plurality of pixel holes arranged in an array.

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