Method for manufacturing mask plate and mask plate

Abstract

The disclosure provides a mask plate manufacturing method and a mask plate. The manufacturing method comprises the following steps: providing a stack structure; removing part of the light-shielding material layer with the hard mask layer as a mask to transfer the pattern of the hard mask layer to the light-shielding material layer to obtain a first intermediate body, and the pattern forms a groove on the light-shielding material layer; removing the hard mask layer for a first target removal time and extending the depth of the groove to remove part of the phase shift material layer to obtain a second intermediate body; measuring the critical dimension of the light-shielding material layer in the second intermediate body; determining a second target removal time according to the critical dimension, a target dimension, and a preset configuration relationship, the preset configuration relationship is used to represent the corresponding relationship between the removal time and the size difference, and the size difference is the difference between the critical dimension of the light-shielding material layer and the target dimension of the phase shift material layer; and removing part of the phase shift material layer of the second intermediate body for the second target removal time to obtain the mask plate. In this way, the size accuracy of the mask plate can be effectively improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of electronic manufacturing technology, and in particular, to a mask plate manufacturing method and a mask plate. BACKGROUND

[0002] A mask plate, also known as a photomask or a mask, is a patterned master used in photolithography in microelectronics and integrated optoelectronics manufacturing, and has been widely used in various fields such as semiconductors, flat panel displays, micro-electro-mechanical systems, etc.

[0003] Phase shift mask (PSM) technology is a relatively common mask technology that can effectively improve pattern contrast and resolution, and hard mask (HM) technology is a mask technology that can improve the precision of the photolithography process and the ability of complex patterns. In the related art, PSM technology and HM technology are combined to meet the mask requirements of more advanced processes, thereby producing integrated circuits with smaller feature sizes and higher performance. However, the HM-PSM technology in the related art has the problem of low size accuracy. SUMMARY

[0004] The following is a summary of the subject matter of the detailed description of the present disclosure. This summary is not intended to limit the scope of protection of the claims.

[0005] In a first aspect, the present disclosure provides a mask plate manufacturing method, the manufacturing method comprising:

[0006] providing a stack structure, the stack structure comprising a transparent base material layer, a phase shift material layer, a light shielding material layer, and a hard mask layer stacked;

[0007] removing part of the light shielding material layer with the hard mask layer as a mask to transfer a pattern of the hard mask layer to the light shielding material layer, to obtain a first intermediate body, the pattern forming a groove on the light shielding material layer;

[0008] removing the hard mask layer for a first target removal time, and extending the depth of the groove to remove part of the phase shift material layer, to obtain a second intermediate body;

[0009] measuring a critical dimension of the light shielding material layer in the second intermediate body;

[0010] determining a second target removal time according to the critical dimension, a target dimension, and a preset configuration relationship, the preset configuration relationship being used to represent a corresponding relationship between a removal time and a dimension difference, the dimension difference being a difference between the critical dimension of the light shielding material layer and the target dimension of the phase shift material layer;

[0011] Continuing to remove the phase shift material layer of the second intermediate body according to the second target removal duration, to obtain a mask plate.

[0012] In some embodiments, the manufacturing method further comprises:

[0013] determining a target linear graph, and taking the target linear graph as the preset configuration relationship.

[0014] In some embodiments, the determining a target linear graph comprises:

[0015] providing n groups of test stack structures, each group of test stack structures comprising a plurality of test stack structures, each test stack structure comprising a test transparent substrate material layer, a test phase shift material layer, a test light shielding material layer, and a test hard mask layer;

[0016] testing each group of test stack structures with different parameter values to obtain a plurality of groups of test data;

[0017] obtaining a plurality of linear graphs from the plurality of groups of test data respectively, each linear graph having a determination coefficient;

[0018] selecting the linear graph corresponding to the largest determination coefficient as the target linear graph.

[0019] In some embodiments, the testing each group of test stack structures with different parameter values comprises:

[0020] etching n groups of test stack structures with different hard mask layer removal durations respectively to obtain n groups of first test intermediates, each group of first test intermediates comprising a plurality of first test intermediates;

[0021] measuring the critical dimension of the test light shielding material layer of each first test intermediate based on m different measurement thresholds respectively to obtain (mxn) first measurement data;

[0022] etching (mxn) first test intermediates with z different phase shift material layer removal durations respectively to obtain (m x n x z) second test intermediates;

[0023] measuring the critical dimension of the test phase shift material layer of (m x n x z) second test intermediates to obtain (m x n x z) second measurement data;

[0024] wherein the z phase shift material layer removal durations, the measurement thresholds corresponding to each phase shift material layer removal duration, the hard mask layer removal durations, the first measurement data, and the second measurement data constitute a group of test data.

[0025] In some embodiments, the obtaining a plurality of linear graphs respectively according to the plurality of sets of test data comprises:

[0026] According to each set of test data, a linear graph of the corresponding relationship between the difference between the first measurement data and the second measurement data and the length of time for removing the phase shift material layer is established, and (m*n) linear graphs are obtained.

[0027] In some embodiments, the length of time for removing the hard mask layer corresponding to the target linear graph is taken as the first target length of time for removal.

[0028] In some embodiments, the measuring the critical dimension of the light-blocking material layer in the second intermediate body comprises:

[0029] The critical dimension of the light-blocking material layer in the second intermediate body is measured based on a target measurement threshold.

[0030] In some embodiments, the measurement threshold corresponding to the target linear graph is taken as the target measurement threshold.

[0031] In some embodiments, the part of the phase shift material layer of the second intermediate body is continuously removed at the second target length of time for removal to obtain a mask plate, which comprises:

[0032] The phase shift material layer of the second intermediate body is continuously etched at the second target length of time for removal, with the light-blocking material layer of the second intermediate body as a mask.

[0033] The mask plate is obtained after removing part of the light-blocking material layer.

[0034] According to a second aspect of the present disclosure, a mask plate is provided, which is obtained by the manufacturing method according to the first aspect.

[0035] In the manufacturing method of the mask plate provided by the present disclosure, the hard mask layer is removed at the first target length of time for removal before the critical dimension of the light-blocking material layer in the second intermediate body is measured. By controlling the length of time for removing the hard mask layer, the second target length of time for removal of etching the phase shift material layer is determined according to the critical dimension, the target dimension and the preset configuration relationship, and then the part of the phase shift material layer of the second intermediate body is continuously removed at the second target length of time for removal. As a result, the critical dimension of the phase shift material layer of the mask plate obtained in this way is closer to the target dimension, thereby effectively improving the dimension accuracy of the mask plate.

[0036] Other aspects can become apparent from the following drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0037] The accompanying drawings, which are incorporated into and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of embodiments of the present disclosure. In these drawings, like reference numerals are used to represent similar elements. The accompanying drawings in the following description are some embodiments of the present disclosure, rather than all embodiments. Those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0038] Figure 1 Flow chart of the method for manufacturing the mask plate according to an exemplary embodiment.

[0039] Fig. 2(a)-(e) is a schematic diagram of the method for manufacturing the mask plate according to an exemplary embodiment.

[0040] Figure 3 Flow chart of the method for manufacturing the mask plate according to another exemplary embodiment.

[0041] Figure 4 Flow chart of step S20 according to an exemplary embodiment.

[0042] Figure 5 Flow chart of step S600 according to an exemplary embodiment.

[0043] Reference Signs :

[0044] 10 - stack structure; 101 - first intermediate body; 102 - second intermediate body; 11 - transparent base material layer; 12 - phase shift material layer; 13 - light shielding material layer; 14 - hard mask layer;

[0045] 20 - mask plate; 21 - transparent base layer; 22 - phase shift layer; 23 - light shielding layer; 24 - phase shift region; 25 - light transmission region. DETAILED DESCRIPTION

[0046] In order to make the purposes, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the disclosed embodiments will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are some but not all of the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present disclosure. It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other arbitrarily without conflict.

[0047] In the related art, the PSM technology and the HM technology are combined to meet the mask requirements of more advanced processes, so as to produce integrated circuits with smaller feature sizes and higher performance. However, the HM-PSM technology in the related art has the problem of low size accuracy.

[0048] As an example, when the HM-PSM technology is used to manufacture a mask plate in the related art, the removal time of the hard mask layer and the etching time of the phase shift material layer are both relied on personal experience, and the final size is controlled through multiple measurements and etching. In this way, the critical dimension of the manufactured mask plate is greatly different from the target size of the product, resulting in low size accuracy.

[0049] To solve the above problems, the embodiments of the present disclosure provide a mask plate manufacturing method, which comprises the following steps: providing a stacked structure, the stacked structure comprising a transparent base material layer, a phase shift material layer, a light shielding material layer and a hard mask layer stacked; removing part of the light shielding material layer with the hard mask layer as a mask to transfer the pattern of the hard mask layer to the light shielding material layer, to obtain a first intermediate body, the pattern forming a groove on the light shielding material layer; removing the hard mask layer for a first target removal time and extending the depth of the groove to remove part of the phase shift material layer to obtain a second intermediate body; measuring the critical dimension of the light shielding material layer in the second intermediate body; determining a second target removal time according to the critical dimension, the target size and a preset configuration relationship, the preset configuration relationship being used to represent the corresponding relationship between the removal time and the size difference, the size difference being the difference between the critical dimension of the light shielding material layer and the target size of the phase shift material layer; continuing to remove part of the phase shift material layer of the second intermediate body for the second target removal time to obtain a mask plate. Before measuring the critical dimension of the material light shielding layer in the second intermediate body, the hard mask layer is removed for the first target removal time, the removal time of the hard mask layer is controlled, then the second target removal time of etching the phase shift material layer is determined according to the critical dimension, the target size and the preset configuration relationship, and then part of the phase shift material layer of the second intermediate body is removed for the second target removal time. The critical dimension of the phase shift material layer of the mask plate obtained in this way is closer to the target size, thereby effectively improving the size accuracy of the mask plate.

[0050] As shown in FIG. 1, Figure 1 The embodiments of the present disclosure provide a mask plate manufacturing method, which specifically comprises the following steps:

[0051] Step S100: providing a stacked structure, the stacked structure comprising a transparent base material layer, a phase shift material layer, a light shielding material layer and a hard mask layer stacked.

[0052] In this step, as shown in FIG. 2(a), the stack structure 10 is the production embryo of the mask plate 20, which includes the hard mask layer 14, the light-blocking material layer 13, the phase shift material layer 12 and the transparent base material layer 11 stacked in sequence. The phase shift material layer 12 is between the light-blocking material layer 13 and the transparent base material layer 11, and the light-blocking material layer 13 is between the phase shift material layer 12 and the hard mask layer 14. For example, in the production of the stack structure 10, the phase shift material layer 12, the light-blocking material layer 13 and the hard mask material layer can be sequentially deposited on the transparent base material, and then a layer of photoresist is coated on the hard mask material layer, a pattern is formed by exposure and development, the hard mask material layer is etched to form the hard mask layer 14, and then the photoresist is removed. The light-blocking material layer 13 blocks light from passing through the phase shift material layer 12 while protecting the phase shift material layer 12. Referring to FIG. 2(e), the light-blocking material layer 13 in the stack structure 10 is used to form the light-blocking layer 23 of the mask plate 20, the phase shift material layer 12 is used to form the phase shift layer 22 of the mask plate 20, and the transparent base material layer 11 is used to form the transparent base layer 21 of the mask plate 20.

[0053] The hard mask layer 14 is an inorganic thin film material generated by a chemical vapor deposition (CVD) technique, which is usually formed of tungsten silicide or titanium nitride (TiN) and the like. The pattern on the hard mask layer 14 is transferred to the light-blocking material layer 13 by an etching process or the like with the hard mask layer 14 as a mask. Since the hard mask layer 14 has high hardness, strong chemical inertness, high melting point, high etching selectivity ratio, and thinner thickness compared to photoresist, it can etch a deeper target depth, thereby enabling the mask plate 20 to meet the mask requirements of more advanced processes.

[0054] The light-blocking material layer 13 is mainly composed of opaque materials, and hard light-blocking materials such as chromium, silicon and iron oxide are usually used. These materials can effectively block light from passing through specific areas of the mask plate 20, especially areas that do not need to be exposed, to form bright and dark areas on the mask plate 20, thereby forming an accurate pattern profile. Among them, chromium is the most commonly used material for the light-blocking layer 23 due to its high mechanical strength and ability to form fine patterns.

[0055] The phase shift material layer 12 is used to simultaneously adjust the phase shift and transmittance through its partial light transmittance, thereby improving the resolution and contrast of imaging. Typical materials include molybdenum silicide (MoSi) and the like.

[0056] The transparent substrate material layer 11 can be made of synthetic quartz glass material. Compared with common glass, quartz glass has the advantages of high light transmittance (especially in the deep ultraviolet band), small thermal expansion coefficient, stable optical properties, and moderate refractive index n, which is conducive to accurate control of the phase of light waves. Therefore, quartz glass is a relatively ideal substrate material.

[0057] Of course, the hard mask layer 14, the light-blocking material layer 13, the phase shift material layer 12, and the transparent substrate material layer 11 can also be made of other materials, which are not limited herein.

[0058] Step S200: removing part of the light-blocking material layer 13 with the hard mask layer as a mask, so as to transfer the pattern of the hard mask layer to the light-blocking material layer, and obtain a first intermediate body, and the pattern forms a groove on the light-blocking material layer.

[0059] In this step, as shown in FIG. 2(b), the light-blocking material layer 13 can be etched along the outline area of the pattern on the hard mask layer 14, or other removal means can be used to make the pattern penetrate through the light-blocking material layer 13, so as to form a groove on the light-blocking material layer 13.

[0060] Exemplarily, before the first intermediate body 101 is obtained by removing part of the light-blocking material layer 13, the parameter can be adjusted so that the critical dimension of the light-blocking material layer 13 of the second intermediate body 102 is greater than the target size, thereby facilitating the subsequent correction of the size.

[0061] Step S300: removing the hard mask layer with a first target removal time length, and extending the depth of the groove to remove part of the phase shift material layer, and obtain a second intermediate body.

[0062] Since the removal time length of the hard mask layer 14 will affect the surface morphology of the second intermediate body 102, and then affect the measurement data of the critical dimension of the light-blocking material layer 13, the error is large when the removal time length of the phase shift material layer 12 is determined according to the measurement data, which affects the size accuracy of the phase shift material layer 12.

[0063] Based on this, as shown in FIG. 2(c), in this step, the first target removal time length of the hard mask layer 14 is first determined, and then the hard mask layer 14 is removed with the first target removal time length, thereby facilitating the improvement of the size accuracy of the phase shift layer 22 in the mask plate 20. In the process of removing the hard mask layer 14, part of the phase shift material layer 12 is removed. Alternatively, it can also be understood that since the thickness of the hard mask layer 14 is extremely thin, it can be considered that the hard mask layer 14 is removed at the same time in the process of removing the phase shift material layer 12 with the first target removal time length.

[0064] The determination of the first target removal time length will be described in detail later.

[0065] Step S400: measure the critical dimension of the light-shielding material layer in the second intermediate body.

[0066] The atomic force microscope (AFM) can provide a real three-dimensional surface map, and does not require special treatment of the sample, can directly observe the nanoscale surface morphology and physical properties, and can avoid irreversible damage to the second intermediate body 102. Referring to FIG. 2(c), by detecting the surface of the second intermediate body 102 and analyzing the detection results, the critical dimension (CD) of the light-shielding material layer 13 in the second intermediate body 102 can be obtained. It can be understood that the CD value refers to the actual size of the pattern formed on the light-shielding material layer 13.

[0067] Step S500: determine the second target removal duration according to the critical dimension, the target size, and a preset configuration relationship, the preset configuration relationship being used to represent the corresponding relationship between the removal duration and the size difference, and the size difference being the difference between the critical dimension of the light-shielding material layer and the target size of the phase shift material layer.

[0068] In this step, the second target removal duration is determined according to the critical dimension, the target size, and the preset configuration relationship, and then the phase shift material layer 12 is removed by the accurate removal duration, which can effectively improve the size accuracy of the phase shift material layer 12, so that the CD value of the phase shift material layer 12 is closer to the target size. The specific determination process of the second target removal duration is described in detail below.

[0069] Step S600: continue to remove part of the phase shift material layer of the second intermediate body by the second target removal duration to obtain a mask plate.

[0070] In this step, as shown in FIG. 2(d), based on the second intermediate body 102, the phase shift material layer 12 is etched along the contour region of the pattern on the light-shielding material layer 13 by the second target removal duration, so that the depth of the groove is deepened, thereby transferring the pattern to the phase shift material layer 12, or other removal means can also be used.

[0071] In this embodiment, before measuring the critical dimension of the light-shielding material layer 23 in the second intermediate body 102, the hard mask layer 14 is removed by the first target removal duration, and by controlling the removal duration of the hard mask layer 14, the second target removal duration for etching the phase shift material layer 12 is determined according to the critical dimension, the target size, and the preset configuration relationship, and then part of the phase shift material layer 12 of the second intermediate body 102 is removed by the second target removal duration, so that the critical dimension of the phase shift material layer 12 of the mask plate 20 obtained in this way is closer to the target size, thereby effectively improving the size accuracy of the mask plate 20.

[0072] In some embodiments, the manufacturing method further comprises the following steps:

[0073] determining a target linear graph as a preset configuration relationship.

[0074] The linear graph can clearly show the trend of data changing with time or other continuous change, so that the target linear graph is taken as the preset configuration relationship, which can make the determination process simpler and faster when determining the second target removal duration according to the critical dimension, the target dimension and the preset configuration relationship, thereby improving the accuracy of the second target removal duration, further improving the size accuracy of the mask plate 20, and also improving the manufacturing efficiency of the mask plate 20.

[0075] In this embodiment, before manufacturing the mask plate 20, the target linear graph is first determined, and the determination of the second target removal duration in the subsequent manufacturing of the mask plate 20 is combined with the target linear graph, thereby ensuring the size accuracy of the manufactured mask plate 20.

[0076] In some embodiments, as shown in Figure 3 determining a target linear graph specifically comprises the following steps:

[0077] Step S10: providing n groups of test stack structures, each group of test stack structures comprising a plurality of test stack structures, each test stack structure comprising a test transparent substrate material layer, a test phase shift material layer, a test light shielding material layer and a test hard mask layer.

[0078] In this step, n groups of test stack structures 10 are provided to determine the target linear graph. The number of groups of test stack structures 10 can be set by oneself, for example, 3 groups, 6 groups, 10 groups, etc.

[0079] Step S20: testing each group of test stack structures with different parameter values to obtain a plurality of groups of test data.

[0080] In this step, the different parameter values may, for example, be different removal durations of the hard mask layer 14, different removal durations of the phase shift material layer 12, etc., so that the linear graph obtained from the test data can represent the corresponding relationship between the removal duration and the size difference, wherein the size difference is the difference between the critical dimension of the light shielding material layer 13 and the target dimension of the phase shift material layer 12.

[0081] Step S30: obtaining a plurality of linear graphs from the plurality of groups of test data, each linear graph having a determination coefficient.

[0082] In this step, a plurality of linear graphs are obtained from the plurality of groups of test data, which can be obtained by software calculation, and the determination coefficient of each linear graph can also be calculated by software. The calculation process is a prior art and will not be described in detail here.

[0083] Step S40: selecting the linear graph corresponding to the maximum determination coefficient as the target linear graph.

[0084] The determination coefficient (R 2 ) of the linear graph is an index for measuring the goodness of fit of the model, and the value is between 0 and 1. The closer to 1, the better the goodness of fit of the model, that is, the higher the degree of explanation of the independent variable to the dependent variable, that is, the closer the predicted value of the model to the actual value.

[0085] By selecting the linear graph corresponding to the maximum determination coefficient as the target linear graph, the accuracy of the second target removal time length can be effectively improved when the second target removal time length is determined according to the key size, the target size and the preset configuration relationship, thereby improving the size precision of the phase shift material layer 12 of the mask plate 20.

[0086] In some embodiments, as shown in Figure 4 , the step of testing each group of test stack structures with different parameter values in step S20 specifically includes the following steps:

[0087] Step S21: etching the n groups of test stack structures with different hard mask layer removal time lengths respectively to obtain n groups of first test intermediates, and each group of first test intermediates includes a plurality of first test intermediates.

[0088] In this step, the n groups of test stack structures 10 are etched with different hard mask layer removal time lengths, for example, the different hard mask layer removal time lengths are 0s, 15s, 20s, etc., which can be set according to experience, etc.

[0089] Step S22: measuring the key size of the test light shielding material layer of each first test intermediate based on m different measurement thresholds for each group of first test intermediates respectively to obtain (m x n) first measurement data.

[0090] In this step, the measurement threshold is a parameter in the measurement process. For example, when the measurement is performed by an atomic force microscope, the received signal is an electronic signal, and the surface topography of the test light shielding material layer is a peak structure, for example. At this time, the starting point and the end point of the CD are defined according to the electronic signal requirements.

[0091] Exemplarily, the lowest part of the peak-shaped structure is defined as 0%, the highest part of the peak-shaped structure is defined as 100%, and different heights between 0% and 100% are, for example, 25%, 50%, 75%, etc. The percentages between 0% and 100% are the measurement thresholds. Taking the measurement threshold with a height of 25% as an example, the height of the 25% measurement threshold is a horizontal line, and the horizontal line has two intersection points on the left side and the right side of the peak-shaped structure, for example, the left intersection point is defined as the starting point of the CD, and the right intersection point is defined as the end point of the CD. The width between the starting point and the end point is the CD value.

[0092] By measuring the critical dimensions of the test phase shift material layer of the first test intermediate body based on m different measurement thresholds, the influence of different measurement thresholds on the removal time of the phase shift material layer is investigated.

[0093] The measurement thresholds can be set according to experience, for example, 25%, 50%, 75%, etc.

[0094] Step S23: etching the (m x n) first test intermediates with z different phase shift material layer removal times to obtain (m x n x z) second test intermediates.

[0095] In this step, the z different phase shift material layer removal times for etching can also be set according to experience, for example, 5s, 10s, 15s, 20s, etc.

[0096] Step S24: measuring the critical dimensions of the test phase shift material layer of the (m x n x z) second test intermediates to obtain (m x n x z) second measurement data.

[0097] The z phase shift material layer removal times, the measurement thresholds corresponding to the various phase shift material layer removal times, the hard mask layer removal time, the first measurement data, and the second measurement data constitute a set of test data.

[0098] In this embodiment, by controlling the data obtained by the hard mask layer removal time, the measurement threshold, and the phase shift material layer removal time, the linear graph can better reflect the corresponding relationship between the removal time and the size difference when determining the linear graph subsequently, thereby facilitating the improvement of the size precision of the phase shift material layer 12 in the mask plate 20.

[0099] In some embodiments, the step of obtaining a plurality of linear graphs from a plurality of sets of test data in step S30 specifically includes the following steps:

[0100] According to each set of test data, a linear graph of the corresponding relationship between the difference between the first measurement data and the second measurement data and the phase shift material layer removal duration is established, and (m x n) linear graphs are obtained.

[0101] The phase shift material layer removal duration is taken as the abscissa, and the difference between the first measurement data and the second measurement data is taken as the ordinate, and a linear graph of the corresponding relationship between the difference between the first measurement data and the second measurement data and the phase shift material layer removal duration is established. When the second target removal duration is determined according to the critical dimension, the target dimension and the preset configuration relationship, the determination process can be made more simple and fast, thereby improving the accuracy of the second target removal duration, further improving the size accuracy of the mask plate 20, and also improving the manufacturing efficiency of the mask plate 20.

[0102] The determination coefficient R 2 The largest linear graph is taken as the target linear graph, in which the target dimension is a known quantity, the critical dimension is the critical dimension measured in step S400, and the difference between the critical dimension and the target dimension is the y value of the linear graph function relationship (y = ax + b). The x value of the function relationship, i.e. the second target removal duration, can be calculated.

[0103] In some embodiments, the hard mask layer removal duration corresponding to the target linear graph is taken as the first target removal duration.

[0104] Each linear graph includes the hard mask layer removal duration corresponding to the linear graph, the measurement threshold, the first measurement data (the critical dimension of the test light shielding material layer 13 of the first test intermediate body), the second measurement data (the critical dimension of the test phase shift material layer 12 of the second test intermediate body), and the phase shift material layer removal duration.

[0105] After the target linear graph is determined, the hard mask layer removal duration in all parameters corresponding to the target linear graph is taken as the first target removal duration. As known from the foregoing, the first target removal duration for removing the hard mask layer 14 is determined first, and then the hard mask layer 14 is removed with the first target removal duration, thereby facilitating the improvement of the size accuracy of the phase shift material layer 12 in the mask plate 20.

[0106] In some embodiments, the measurement of the critical dimension of the light shielding material layer in the second intermediate body in step S400 specifically includes the following steps:

[0107] The critical dimension of the light shielding material layer in the second intermediate body is measured based on the target measurement threshold.

[0108] By measuring the critical dimension of the light shielding material layer 13 in the second intermediate body 102 based on the target measurement threshold, the measured critical dimension is more conducive to improving the accuracy of the determined second target removal duration, thereby facilitating more accurate critical dimension of the phase shift material layer 12 in the mask plate 20, and improving the size accuracy of the phase shift material layer 12 in the mask plate 20.

[0109] In some embodiments, the measurement threshold corresponding to the target linear graph is taken as the target measurement threshold.

[0110] As can be seen from the foregoing, each linear graph includes a hard mask layer removal duration corresponding to the linear graph, a measurement threshold, first measurement data (critical dimension of the test light shielding material layer 13 of the first test intermediate body), second measurement data (critical dimension of the test phase shift material layer 12 of the second test intermediate body), and a phase shift material layer removal duration.

[0111] After the target linear graph is determined, the measurement threshold in all parameters corresponding to the target linear graph is taken as the target measurement threshold. By measuring the critical dimension of the light shielding material layer 13 in the second intermediate body 102 based on the target measurement threshold, the measured critical dimension is more conducive to improving the accuracy of the determined second target removal duration, thereby facilitating more accurate critical dimension of the phase shift material layer 12 in the mask plate 20, and improving the size accuracy of the phase shift material layer 12 in the mask plate 20.

[0112] In some embodiments, as shown in Figure 5 The step S600 specifically includes the following steps:

[0113] Step S610: continuing to etch the phase shift material layer of the second intermediate body with the light shielding material layer of the second intermediate body as a mask for a second target removal duration.

[0114] In this step, referring to FIG. 2(d), based on the second intermediate body 102, the phase shift material layer 12 is etched for a second target removal duration along the profile area of the pattern on the light shielding material layer 13, so that the depth of the groove is deepened, thereby transferring the pattern to the phase shift material layer 12,

[0115] Step S620: obtaining a mask plate after removing part of the light shielding material layer.

[0116] In this step, referring to FIG. 2(e), the light transmission area of the mask plate 20 includes light transmission areas 25 and phase shift areas 24 arranged alternately, and when light passes through the mask plate 20 through the light transmission areas 25 and the phase shift areas 24 respectively, a 180-degree phase difference can be generated to obtain a clear-edged pattern. At the same time, the light transmission area of the mask plate 20 also has a high light transmission rate, which can ensure that enough light can pass through and participate in imaging, thereby making the light pass through the phase shift area 24, and the light shielding material layer 13 on the phase shift area 24 needs to be removed.

[0117] In the embodiment, the mask plate 20 obtained through the above steps not only has high size precision of the phase shift layer 22 of the mask plate 20, but also can improve the contrast and resolution of the pattern of the mask plate 20, thereby improving the imaging effect of the mask plate 20.

[0118] As shown in FIG. 2(e), the embodiment provides a mask plate 20, which can be obtained by using the manufacturing method in any of the above embodiments. The mask plate 20 provided by the embodiment includes the light shielding layer 23, the phase shift layer 22 and the transparent substrate layer 21.

[0119] In the process of manufacturing the mask plate 20, the hard mask layer 14 is removed by using the first target removal time length before the key size of the material light shielding layer 23 in the second intermediate body 102 is measured, and then the removal time length of the hard mask layer 14 is controlled, and then the second target removal time length of etching the phase shift material layer 12 is determined according to the key size, the target size and the preset configuration relationship, and then the part of the phase shift material layer 12 of the second intermediate body 102 is continuously removed by using the second target removal time length. The key size of the phase shift layer 22 of the mask plate 20 obtained in this way is closer to the target size, thereby effectively improving the size precision of the mask plate 20.

[0120] The embodiments or implementations in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the embodiments can be referred to each other.

[0121] In the description of the specification, the description of the terms “embodiment”, “exemplary embodiment”, “some implementations”, “illustrative implementation”, “example” and the like means that the specific features, structures, materials or characteristics described in combination with the implementation or example are included in at least one implementation or example of the disclosure.

[0122] In the specification, the illustrative description of the above terms does not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more implementations or examples in a suitable manner.

[0123] In the description of the disclosure, it should be noted that the terms “center”, “upper”, “lower”, “left”, “right”, “vertical”, “horizontal”, “inner”, “outer” and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the disclosure.

[0124] It can be understood that the terms "first", "second" and the like used in the present disclosure can be used in the present disclosure to describe various structures, but these structures are not limited by these terms. These terms are only used to distinguish the first structure from the other structure.

[0125] In one or more drawings, identical elements are denoted by like reference numerals. For the purpose of clarity, not every component can be called out in every drawing. Furthermore, some components can not be shown in some drawings to avoid confusion. For the sake of brevity, some structures obtained after several steps can be described in one figure. Many specific details of the present disclosure are described below in order to provide a thorough understanding of the present disclosure. However, as will be readily understood by one skilled in the art, the present disclosure can be practiced without incorporating these specific details.

[0126] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present disclosure.

Claims

1. A method of manufacturing a mask blank, characterized by, The manufacturing method comprises: providing a stack structure comprising a transparent base material layer, a phase shift material layer, a light shielding material layer and a hard mask layer arranged in a stack; using the hard mask layer as a mask, removing part of the light shielding material layer to transfer a pattern of the hard mask layer to the light shielding material layer, to obtain a first intermediate body, the pattern forming a groove on the light shielding material layer; removing the hard mask layer for a first target removal duration and extending the depth of the groove to remove part of the phase shift material layer, to obtain a second intermediate body; measuring a critical dimension of the light shielding material layer in the second intermediate body; determining a second target removal duration according to the critical dimension, a target dimension and a preset configuration relationship, the preset configuration relationship being used to represent a corresponding relationship between a removal duration and a dimension difference, the dimension difference being a difference between the critical dimension of the light shielding material layer and the target dimension of the phase shift material layer; continuing to remove part of the phase shift material layer of the second intermediate body for the second target removal duration, to obtain a mask plate.

2. The method of manufacturing a mask according to claim 1, wherein The manufacturing method further comprises: determining a target linear graph, and using the target linear graph as the preset configuration relationship.

3. The method of manufacturing a mask according to claim 2, wherein The determination of the target linear graph comprises: providing n groups of test stack structures, each group of test stack structures comprising a plurality of test stack structures, each test stack structure comprising a test transparent base material layer, a test phase shift material layer, a test light shielding material layer and a test hard mask layer; testing each group of test stack structures with different parameter values to obtain a plurality of groups of test data; obtaining a plurality of linear graphs according to the plurality of groups of test data, each linear graph having a determination coefficient; selecting the linear graph corresponding to the largest determination coefficient as the target linear graph.

4. The method of manufacturing a mask according to claim 3, wherein The testing of each group of test stack structures with different parameter values comprises: etching n groups of test stack structures with different hard mask layer removal durations respectively to obtain n groups of first test intermediate bodies, each group of first test intermediate bodies comprising a plurality of first test intermediate bodies; measuring a critical dimension of a test light shielding material layer of each first test intermediate body based on m different measurement thresholds respectively to obtain m×n first measurement data; etching m×n first test intermediate bodies with z different phase shift material layer removal durations respectively to obtain m×n×z second test intermediate bodies; measuring a critical dimension of a test phase shift material layer of the m×n×z second test intermediate bodies to obtain m×n×z second measurement data; wherein the z phase shift material layer removal durations, the measurement thresholds corresponding to the various phase shift material layer removal durations, the hard mask layer removal durations, the first measurement data and the second measurement data constitute a group of test data.

5. The method of manufacturing a mask according to claim 4, wherein The obtaining of a plurality of linear graphs according to the plurality of groups of test data comprises: establishing a linear graph of a corresponding relationship between a difference between the first measurement data and the second measurement data and the phase shift material layer removal duration according to each group of test data, to obtain m×n linear graphs.

6. The method of manufacturing a mask according to claim 4, wherein The hard mask layer removal duration corresponding to the target linear graph is used as the first target removal duration.

7. The method of manufacturing a mask according to claim 4, wherein The measuring the critical dimension of the light-shielding material layer in the second intermediate body comprises: measuring the critical dimension of the light-shielding material layer in the second intermediate body based on a target metrology threshold.

8. The method of manufacturing a mask according to claim 7, wherein The metrology threshold corresponding to the target linear graph is the target metrology threshold.

9. The method of manufacturing a mask according to any one of claims 1 to 8, wherein continuing to remove the part of the phase shift material layer of the second intermediate body with the second target removal duration to obtain a mask plate, comprising: continuing to etch the phase shift material layer of the second intermediate body with the second target removal duration, taking the light-shielding material layer of the second intermediate body as a mask; obtaining the mask plate after removing part of the light-shielding material layer.

10. A mask plate, characterized by, The mask plate is obtained by the manufacturing method in any one of claims 1 to 9.

Images