Photomask pattern design method, photomask and manufacturing method thereof

Abstract

The invention relates to a design method of a photomask pattern, a photomask and a manufacturing method of the photomask. The method comprises the steps of obtaining a main graph; designing a plurality of different auxiliary graphs based on different auxiliary graph rules; edge classification is conducted on the main graph based on symmetry to obtain at least one pair of symmetrical areas, and the two symmetrical areas in the same pair are located on the outer side of the main graph and distributed in a central symmetry mode with the center of the main graph as the center; different auxiliary patterns are arranged in the two symmetrical areas of the same pair respectively; and combining and outputting the main pattern and the auxiliary pattern in the symmetric region to obtain a photomask pattern. According to the method provided by the invention, the setting types and the setting number of the auxiliary patterns in unit area can be increased, so that the correction precision of the auxiliary patterns on the main pattern can be ensured and improved while the pattern area of the photomask is effectively saved, and the correction effect is effectively improved.

Description

Technical Field

[0001] The present application relates to the semiconductor field, and in particular to a mask pattern design method, a mask and a manufacturing method thereof. Background Art

[0002] Sub-resolution Assistant Feature (SRAF) is an important technical means for improving the resolution of the mask in the photolithography process. This technical means usually includes: first setting the main pattern on the substrate, and arranging a number of auxiliary patterns around the main pattern according to certain rules to obtain the mask pattern; then using the mask pattern to prepare the mask, and using the aforementioned auxiliary patterns to correct defects such as shape distortion and line loss at the edge of the main pattern, so as to ensure that the obtained mask meets the design requirements.

[0003] However, due to the limitations of current process levels and mask layout area, the correction effect of the SRAF process still has much room for improvement. Summary of the invention

[0004] Based on this, it is necessary to provide a design method for a mask pattern, a mask and a production method thereof to address the above-mentioned technical problems. While effectively saving the area of ​​the mask pattern, it can also increase the types and number of auxiliary patterns per unit area, which is beneficial to ensure and improve the correction accuracy of the auxiliary pattern to the main pattern in the subsequent process steps of transferring the mask pattern, thereby effectively improving the correction effect.

[0005] On the one hand, some embodiments of the present application provide a method for designing a mask pattern, comprising the following steps.

[0006] Get the main graphic;

[0007] Design a variety of different auxiliary graphics based on different auxiliary graphic rules;

[0008] Based on the symmetry, the edge of the main figure is classified to obtain at least one pair of symmetrical regions, wherein the two symmetrical regions of the same pair are both located outside the main figure and are centrally symmetrically distributed around the center of the main figure;

[0009] Different auxiliary graphics are respectively arranged in two symmetrical areas of the same pair;

[0010] The main pattern and the auxiliary pattern located in the symmetrical area are combined and output to obtain the mask pattern.

[0011] In the embodiment of the present application, a main pattern is obtained, and a symmetrical region of the main pattern is obtained; and multiple auxiliary patterns are obtained based on different auxiliary pattern rules; and then each auxiliary pattern is correspondingly arranged in the aforementioned symmetrical region, and the auxiliary patterns in the two symmetrical regions of the same pair are formed based on different rules. In this way, multiple different auxiliary patterns generated based on multiple different rules can be arranged on the outside of the main pattern at the same time, which effectively saves the area of ​​the mask pattern and is also beneficial in the subsequent process step of transferring the mask pattern, ensuring and improving the correction accuracy of the auxiliary pattern to the main pattern, thereby effectively improving the correction effect.

[0012] In some embodiments, the obtaining of the main pattern includes: designing a plurality of parallel and spaced line patterns as the main pattern; and the two symmetrical regions of the same pair are respectively located on opposite sides of the main pattern.

[0013] In some embodiments, obtaining the main pattern includes: designing a plurality of contact hole patterns arranged in an array as the main pattern; the two symmetrical regions of the same pair are respectively located on opposite sides of the main pattern and / or at opposite vertices of the main pattern.

[0014] In some embodiments, each auxiliary graphic includes a plurality of sub-auxiliary graphics arranged at intervals; among different auxiliary graphics, at least one of the width of the sub-auxiliary graphics, the number of sub-auxiliary graphics, the spacing between adjacent sub-auxiliary graphics, and the spacing between the auxiliary graphic and the main graphic is different from each other.

[0015] On the other hand, some embodiments of the present application provide a method for making a mask, wherein the mask includes an OPC test mask, and the method for making the mask includes designing a mask pattern using the mask pattern design method described in some of the aforementioned embodiments. The technical advantages possessed by the mask pattern design method described in some of the aforementioned implementations are also possessed by the method for making the mask, which will not be repeated here.

[0016] In some embodiments, the method for manufacturing the photomask further includes the following steps.

[0017] Providing a light-transmitting substrate, wherein the light-transmitting substrate is covered with a light-shielding layer;

[0018] The light shielding layer is patterned based on the mask pattern, and the mask pattern is transferred to the light-transmitting substrate to obtain a mask.

[0019] On the other hand, some embodiments of the present application provide a mask as a practical application of the mask manufacturing method described in some of the aforementioned embodiments. The mask includes an OPC test mask. The mask also has the technical advantages possessed by the mask manufacturing method described in some of the aforementioned implementations, which will not be repeated here.

[0020] By way of example, the mask includes a mask pattern, which includes: a main pattern and a plurality of different auxiliary patterns; wherein the outer side of the main pattern has at least one pair of symmetrical regions, the two symmetrical regions of the same pair are both located outside the main pattern and are symmetrically distributed with respect to the center of the main pattern; the plurality of different auxiliary patterns are respectively located in the symmetrical regions, and the auxiliary patterns in the two symmetrical regions of the same pair are different from each other.

[0021] In some embodiments, the main pattern includes a plurality of line patterns arranged in parallel and at intervals; two symmetrical regions of the same pair are located on opposite sides of the main pattern.

[0022] In some embodiments, the main pattern includes a plurality of contact hole patterns arranged in an array; the two symmetrical regions of the same pair are respectively located at opposite sides of the main pattern and / or at opposite corners of the main pattern.

[0023] In some embodiments, each auxiliary graphic includes a plurality of sub-auxiliary graphics arranged at intervals; among different auxiliary graphics, at least one of the width of the sub-auxiliary graphics, the number of sub-auxiliary graphics, the spacing between adjacent sub-auxiliary graphics, and the spacing between the auxiliary graphic and the main graphic is different from each other. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of a process for designing a mask pattern provided in an embodiment of the present application;

[0026] Figure 2 is a schematic structural diagram of a main pattern provided in an embodiment of the present application, and is also a schematic structural diagram of a structure obtained after step S300 in a method for designing a mask pattern provided in an embodiment;

[0027] Figure 3 A schematic diagram of the structure of another main graphic provided in an embodiment of the present application;

[0028] Figure 4 A schematic diagram of a partial structure of a structure obtained by disposing an auxiliary pattern outside a main pattern provided in an embodiment of the present application;

[0029] Figure 5 A schematic diagram of a partial structure of another structure obtained by disposing an auxiliary pattern outside a main pattern provided in an embodiment of the present application;

[0030] Figure 6 A schematic diagram of a structure obtained after step S400 in a method for designing a mask pattern provided in an embodiment of the present application;

[0031] Figure 7 A schematic structural diagram of a structure obtained after another step S300 in the method for designing a mask pattern provided in an embodiment of the present application;

[0032] Figure 8 A schematic diagram of a partial structure of another structure obtained by setting an auxiliary pattern outside a main pattern provided in an embodiment of the present application;

[0033] Fig. 9 A schematic diagram of a partial structure of another structure obtained by setting an auxiliary pattern outside a main pattern provided in an embodiment of the present application;

[0034] Fig.10 A schematic diagram of a partial structure of another structure obtained by setting an auxiliary pattern outside a main pattern provided in an embodiment of the present application;

[0035] Fig.11 A schematic diagram of a partial structure of a structure obtained after step S500 in a method for designing a mask pattern provided in an embodiment of the present application;

[0036] Fig.12 A schematic diagram of a structure obtained after performing MRC on an auxiliary graphic provided in an embodiment of the present application;

[0037] Fig.13 A schematic diagram of another structure obtained after performing MRC on an auxiliary graphic provided in an embodiment of the present application;

[0038] Fig.14 A schematic diagram of the structure of a photomask pattern provided in one embodiment of the present application;

[0039] Fig.15 A schematic flow chart of a method for manufacturing a photomask provided in another embodiment of the present application;

[0040] Fig.16 A schematic diagram of a top view structure of a photomask obtained by a photomask manufacturing method provided in another embodiment of the present application;

[0041] Fig.17 A schematic top view of another photomask obtained by a photomask manufacturing method provided in another embodiment of the present application.

[0042] Description of reference numerals:

[0043] 10-main graphic, 11A-line graphic, 11B-contact hole graphic, 20-auxiliary graphic, 20A-first auxiliary graphic, 20B-second auxiliary graphic, 21A-first sub-auxiliary graphic, 21B-second sub-auxiliary graphic, Z1A-first area, Z1B-second area, Z2A-third area, Z2B-fourth area, 30-transparent substrate. DETAILED DESCRIPTION

[0044] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0046] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element, or connected to the other element through an intermediate element. In addition, the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if there is transmission of electrical signals or data between the connected objects.

[0047] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0048] Sub-resolution Assistant Feature (SRAF) is an important technical means for improving the resolution of the mask in the photolithography process. This technical means usually includes: first setting the main pattern on the substrate, and arranging a number of auxiliary patterns around the main pattern according to certain rules to obtain the mask pattern; then using the mask pattern to prepare the mask, and using the aforementioned auxiliary patterns to correct defects such as shape distortion and line loss at the edge of the main pattern, so as to ensure that the obtained mask meets the design requirements.

[0049] However, due to the limitations of current process levels and mask layout area, the correction effect of the SRAF process still has much room for improvement.

[0050] See also Figure 1 Some embodiments of the present application provide a method for designing a mask pattern, including steps S100 to S500.

[0051] S100, obtaining a main graphic.

[0052] S200, designs a variety of different auxiliary graphics based on different auxiliary graphic rules.

[0053] S300, edge classification of the main figure is performed based on symmetry to obtain at least one pair of symmetrical regions, wherein the two symmetrical regions of the same pair are both located outside the main figure and are centrally symmetrically distributed with respect to the center of the main figure.

[0054] S400, different auxiliary graphics are respectively arranged in two symmetrical regions of the same pair.

[0055] S500, merging the main pattern and the auxiliary pattern located in the symmetrical area and outputting them to obtain a mask pattern.

[0056] In the embodiment of the present application, a main pattern is obtained, and a symmetrical region of the main pattern is obtained; and multiple auxiliary patterns are obtained based on different auxiliary pattern rules; and then each auxiliary pattern is correspondingly arranged in the aforementioned symmetrical region, and the auxiliary patterns in the two symmetrical regions of the same pair are formed based on different rules. In this way, multiple different auxiliary patterns generated based on multiple different rules can be arranged on the outside of the main pattern at the same time, which effectively saves the area of ​​the mask pattern and is also beneficial in the subsequent process step of transferring the mask pattern, ensuring and improving the correction accuracy of the auxiliary pattern to the main pattern, thereby effectively improving the correction effect.

[0057] In step S100, refer to Figure 1 S100 and Figure 2 and Figure 3 , obtain the main graphic 10.

[0058] Here, the main pattern 10 is a main target pattern that needs to be transferred to a photomask in a subsequent step.

[0059] For example, the main pattern 10 may include: a plurality of line patterns 11A arranged in parallel and spaced apart; or may also include: a plurality of contact hole patterns 11B arranged in an array. Among them, the plurality of line patterns arranged in parallel and spaced apart may be used, for example, in the subsequent preparation process of the active area array; the plurality of contact hole patterns arranged in an array may be used, for example, in the subsequent preparation process of the capacitor array. The shape of the main pattern 10 is not limited thereto. In other examples, the main pattern 10 may also include: a plurality of line patterns 11A and a plurality of contact hole patterns 11B at the same time. This application does not limit this.

[0060] In order to more clearly illustrate the method provided by the present application and to more conveniently show the structural changes corresponding to each step, the following embodiments and drawings of the specification respectively take the main graphic 10 including: a plurality of line graphics 11A arranged in parallel and spaced apart; and the main graphic 10 including: a plurality of contact hole graphics 11B arranged in an array as examples, and explain and illustrate them one by one.

[0061] See also Figures 3 to 5 It is understood that the following describes steps S200 to S400 in detail with the main pattern 10 comprising: a plurality of line patterns 11A arranged in parallel and at intervals.

[0062] In step S200, refer to Figure 1 S200 and Figures 4 to 6 , a variety of different auxiliary graphics 20 are designed based on different auxiliary graphic rules.

[0063] Here, the auxiliary graphic rule refers to a set of rule bases formed based on historical data or personnel experience of performing optical proximity correction (OPC) in this field. The generation rules and specific parameters of the auxiliary graphic 20 can be directly determined according to the relevant morphological parameters and process parameters of the main graphic 10.

[0064] For example, the generation process of the auxiliary graphic 20 includes: providing a rule library, in which a variety of different auxiliary graphic rules are stored; determining at least two auxiliary graphic rules (for example, rule A and rule B) in the rule library according to the morphological parameters of the main graphic 10 and the corresponding process parameters; and generating auxiliary graphics 20 (for example, a first auxiliary graphic 20A and a second auxiliary graphic 20B) based on the aforementioned rule A and rule B respectively.

[0065] For example, the data for establishing the rule base may come from the accumulated experience of personnel during the product development stage or the formal production stage, or may also come from existing rule bases provided by other manufacturers with the same or similar product structures and process equipment.

[0066] For example, the relevant morphological parameters of the main pattern 10 may include: a width value, a length value, a depth value, a height value or a sidewall angle value.

[0067] By way of example, the process parameters may include, for example, exposure wavelength, exposure light intensity, photoresist resolution, and exposure depth of field.

[0068] For example, the parameters in the auxiliary pattern rule may include: the number of sub-auxiliary patterns in the auxiliary pattern 20, the width of the sub-auxiliary patterns, the spacing between adjacent sub-auxiliary patterns, and the spacing between the auxiliary pattern and the main pattern. It can be understood that the auxiliary patterns generated based on different auxiliary pattern rules are different in terms of quantity and morphological parameters.

[0069] Please continue reading Figure 4 and Figure 5 In some embodiments, each auxiliary graphic 20 includes a plurality of sub-auxiliary graphics arranged at intervals; in different auxiliary graphics 20, at least one of the width of the sub-auxiliary graphics, the number of sub-auxiliary graphics, the spacing between adjacent sub-auxiliary graphics, and the spacing between the auxiliary graphics and the main graphics is different from each other.

[0070] For example, the first auxiliary pattern 20A includes a plurality of first sub-auxiliary patterns 21A arranged at intervals; the second auxiliary pattern 20B includes a plurality of second sub-auxiliary patterns 21B arranged at intervals. Wherein, any one of the width W1 of the first sub-auxiliary pattern 21A and the width W2 of the second sub-auxiliary pattern 21B, the spacing L1 between adjacent first sub-auxiliary patterns 21A in the first auxiliary pattern 20A and the spacing L2 between adjacent second sub-auxiliary patterns 21B in the second auxiliary pattern 20B, and the spacing S1 between the first auxiliary pattern 20A and the main pattern 10 and the spacing S2 between the second auxiliary pattern 20B and the main pattern 10 are different or all are different.

[0071] In step S300, refer to Figure 1 S300 and Figure 2 , the edge of the main figure 10 is classified based on symmetry to obtain at least one pair of symmetrical regions, and the two symmetrical regions of the same pair are both located outside the main figure 10 and are centrally symmetrically distributed with respect to the center of the main figure 10.

[0072] Here, edge classification of the main graphic 10 based on symmetry means: by analyzing the symmetry of the main graphic 10, its symmetry type, symmetry center and / or symmetry axis are determined, and then its symmetric edge is determined, so as to obtain a symmetric area adjacent to its symmetric edge.

[0073] For example, in an embodiment where the main pattern 10 includes: a plurality of line patterns 11A arranged in parallel and at intervals, two symmetrical regions of the same pair are respectively located on two opposite sides of the main pattern.

[0074] For example, a pair of symmetrical regions of the main graph 10 is determined to include: a first region Z1A and a second region Z1B, wherein the first region Z1A and the second region Z1B are located on opposite sides of the main graph 10 and are symmetrically distributed about the symmetry axis of the main graph 10 .

[0075] In step S400, refer to Figure 1 S400 and Figures 4 to 6 Different auxiliary patterns 20 are respectively arranged in two symmetrical regions of the same pair.

[0076] For example, the first auxiliary pattern 20A obtained in the aforementioned step S200 is disposed in the first area Z1A; and the second auxiliary pattern 20B is disposed in the second area Z1B.

[0077] It should be emphasized that the first auxiliary graphic 20A and the second auxiliary graphic 20B are generated based on different auxiliary graphic rules. For example, the first auxiliary graphic 20A is generated based on auxiliary graphic rule A; the second auxiliary graphic 20B is generated based on auxiliary graphic rule B. Here, ensuring that the auxiliary graphics in the two symmetrical areas of the same pair are generated based on different auxiliary graphic rules is conducive to using a variety of different auxiliary graphic rules in the same area, so as to effectively improve the correction accuracy of the auxiliary graphic 20 on the main graphic 10.

[0078] See also Figure 7 To understand the figure, the following supplementary explanation of steps S300 to S400 is given by assuming that the main pattern 10 includes: a plurality of contact hole patterns 11B arranged in an array.

[0079] In step S300, refer to Figure 1 S300 and Figure 7 , the edge of the main figure 10 is classified based on symmetry to obtain at least one pair of symmetrical regions, and the two symmetrical regions of the same pair are both located outside the main figure 10 and are centrally symmetrically distributed with respect to the center of the main figure 10.

[0080] For example, in an embodiment where the main pattern 10 includes: a plurality of contact hole patterns 11B arranged in an array, the two symmetrical regions of the same pair are respectively located at opposite sides of the main pattern 10 and / or at opposite corners of the main pattern. Specifically, the two symmetrical regions of the same pair may be located only at opposite sides of the main pattern 10, or only at opposite corners of the main pattern 10, or may be located at both opposite sides and opposite corners of the main pattern 10.

[0081] For example, it is determined that the main figure 10 includes two pairs of symmetrical areas, namely: a first area Z1A, a second area Z1B, a third area Z2A and a fourth area Z2B. The first area Z1A and the second area Z1B are located on two opposite sides of the main figure 10, and the third area Z2A and the fourth area Z2B are located on the other opposite sides of the main figure 10.

[0082] In step S400, refer to Figure 1 S400 and Figures 8 to 11 Different auxiliary patterns 20 are respectively arranged in two symmetrical regions of the same pair.

[0083] For example, the first auxiliary pattern 20A is arranged in the first area Z1A; the second auxiliary pattern 20B is arranged in the second area Z1B; the second auxiliary pattern 20B is arranged in the third area Z2A; and the first auxiliary pattern 20A is arranged in the fourth area Z2B. Here, the aforementioned arrangement rule of the auxiliary pattern is continued, that is, the auxiliary patterns in the two symmetrical areas of the same pair are respectively generated based on different auxiliary pattern rules.

[0084] It is worth mentioning that when the auxiliary patterns are arranged in each area, a mask rule check (MRC) can be performed simultaneously to ensure that the obtained mask pattern can meet the relevant process requirements.

[0085] For example, see Fig.12 and Fig.13 Based on the MRC rule, the layout position and morphology parameters of the first auxiliary graphic 20A partially located at the top corners of the first area Z1A and the fourth area Z2B are adjusted accordingly; and the layout position and morphology parameters of the second auxiliary graphic 20B partially located at the top corners of the second area Z1B and the third area Z2A are adjusted accordingly.

[0086] For example, the adjustment objects of the MRC rule include: the line width and spacing of each sub-main pattern 11 in the main pattern 10, and the line width and spacing of the sub-auxiliary patterns in each auxiliary pattern.

[0087] For example, the adjustment objects of the MRC rule include: the line width and spacing of the main pattern 10 and each auxiliary pattern 20 located in the vertex area.

[0088] By way of example, the adjustment objects of the MRC rule include: the area of ​​the main graphic 10 and the areas of each auxiliary graphic 20 .

[0089] In the above embodiments, by performing MRC on the main pattern 10 and each auxiliary pattern 20, pattern defects can be discovered and resolved in a timely manner, thereby ensuring that a mask pattern with better morphology quality can be obtained in subsequent steps.

[0090] In step S500, refer to Figure 1 S500 and Fig.14 , the main pattern 10 and the auxiliary pattern 20 located in the symmetrical area are combined and output to obtain a mask pattern.

[0091] For example, the main pattern 10 and each auxiliary pattern 20 can be output as a mask pattern to a related process device, and a mask can be obtained. The mask can have relatively accurate morphological features of the main pattern 10 and avoid the morphological features of the auxiliary pattern 20.

[0092] See also Fig.15 Some embodiments of the present application provide a method for making a mask, the mask including an OPC test mask; the method for making a mask includes designing a mask pattern using the mask pattern design method described in some of the aforementioned embodiments. The technical advantages possessed by the mask pattern design method described in some of the aforementioned embodiments are also possessed by the method for making a mask, which will not be described in detail here.

[0093] For example, the method for manufacturing the photomask includes steps S10 to S30.

[0094] S10, design mask graphics.

[0095] S20, providing a light-transmitting substrate, wherein a surface of the light-transmitting substrate is covered with a light-shielding layer.

[0096] S30, patterning the light shielding layer based on the mask pattern, and transferring the mask pattern to the light-transmitting substrate to obtain a mask.

[0097] In step S10, refer to Fig.15 S10 and Fig.14 , design the mask graphics.

[0098] For example, the mask pattern design method described in some of the aforementioned embodiments may be used to design the mask pattern.

[0099] By way of example, the mask pattern may include a main pattern 10 and a plurality of auxiliary patterns 20 .

[0100] For example, the main pattern 10 may include: a plurality of line patterns arranged in parallel and spaced apart; or may include: a plurality of contact hole patterns arranged in an array. In the following embodiments and drawings of the specification, the main pattern 10 includes: a plurality of contact hole patterns 11B arranged in an array as an example for explanation and illustration.

[0101] By way of example, the auxiliary pattern 20 includes: a first auxiliary pattern 20A and a second auxiliary pattern 20B, wherein the first auxiliary pattern 20A is generated based on the auxiliary pattern rule A; and the second auxiliary pattern 20B is generated based on the auxiliary pattern rule B.

[0102] For example, each auxiliary pattern 20 includes a plurality of sub-auxiliary patterns arranged at intervals; in different auxiliary patterns 20, at least one of the width of the sub-auxiliary patterns, the number of sub-auxiliary patterns, the spacing between adjacent sub-auxiliary patterns, and the spacing between the auxiliary pattern and the main pattern is different from each other.

[0103] By way of example, the first auxiliary pattern 20A includes a plurality of first sub-auxiliary patterns 21A arranged at intervals; and the second auxiliary pattern 20B includes a plurality of second sub-auxiliary patterns 21B arranged at intervals.

[0104] For example, each auxiliary graphic 20 is arranged in a symmetrical area outside the main graphic 10. For example, two opposite sides of the main graphic 10 are the first area Z1A and the second area Z1B respectively; the other opposite sides of the main graphic 10 are the third area Z2A and the fourth area Z2B respectively. Among them, the first auxiliary graphic 20A is arranged in the first area Z1A; the second auxiliary graphic 20B is arranged in the second area Z1B; the second auxiliary graphic 20B is arranged in the third area Z2A; and the first auxiliary graphic 20A is arranged in the fourth area Z2B. Here, the arrangement rules of the auxiliary graphics in some of the aforementioned embodiments are continued, that is, to ensure that the auxiliary graphics in the two symmetrical areas of the same pair are generated based on different auxiliary graphic rules.

[0105] In step S20, refer to Fig.15 S20 and Fig.16 , providing a light-transmitting substrate 30, the surface of which is covered with a light-shielding layer.

[0106] For example, the material of the light-transmitting substrate 30 includes transparent materials such as quartz glass, soda glass or borosilicate glass.

[0107] For example, the material of the light shielding layer includes: opaque materials such as metal chromium, metal aluminum or metal molybdenum.

[0108] In step S30, refer to Fig.15 S30 and Figure 16 to Figure 17 , the light shielding layer is patterned based on the mask pattern, and the mask pattern is transferred to the transparent substrate 30 to obtain a mask.

[0109] For example, an etching process may be used to pattern the light shielding layer, so as to facilitate accurate transfer of the mask pattern to the transparent substrate 30 .

[0110] Please continue reading Fig.16 and Fig.17 In some embodiments, a photomask is provided, which is formed by using the photomask manufacturing method described in some of the above embodiments. The photomask includes an OPC test photomask.

[0111] For example, the mask includes a mask pattern, which includes: a main pattern 10 and a plurality of different auxiliary patterns 20; wherein the outer side of the main pattern 10 has at least one pair of symmetrical areas, the two symmetrical areas of the same pair are both located on the outer side of the main pattern 10, and are centrally symmetrically distributed with respect to the center of the main pattern 10; the plurality of different auxiliary patterns 20 are respectively located in the symmetrical areas, and the auxiliary patterns 20 in the two symmetrical areas of the same pair are different from each other.

[0112] For example, the main pattern 10 includes a plurality of line patterns 11A arranged in parallel and at intervals; two symmetrical regions of the same pair are located at two opposite sides of the main pattern 10 .

[0113] For example, the main pattern 10 includes a plurality of contact hole patterns 11B arranged in an array; the two symmetrical regions of the same pair are respectively located at opposite sides of the main pattern 10 and / or at opposite corners of the main pattern. Specifically, the two symmetrical regions of the same pair may be located only at opposite sides of the main pattern 10, or only at opposite corners of the main pattern 10, or at both opposite sides and opposite corners of the main pattern 10.

[0114] For example, each auxiliary pattern 20 includes a plurality of sub-auxiliary patterns arranged at intervals; in different auxiliary patterns, at least one of the width of the sub-auxiliary patterns, the number of sub-auxiliary patterns, the spacing between adjacent sub-auxiliary patterns, and the spacing between the auxiliary pattern and the main pattern is different from each other.

[0115] For example, the photomask further includes: a transparent substrate 30 and a light shielding layer covering the transparent substrate 30 . The photomask pattern is located on the transparent substrate 30 .

[0116] For example, the material of the light-transmitting substrate 30 includes transparent materials such as quartz glass, soda glass or borosilicate glass.

[0117] For example, the material of the light shielding layer includes: opaque materials such as metal chromium, metal aluminum or metal molybdenum.

[0118] In the above embodiments of the present application, unless otherwise specified herein, the execution of each step in the method is not strictly limited in order, and these steps may not necessarily be executed in the order described, but may be executed in other ways. Moreover, at least a part of any step may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but may be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but may be executed in turn or alternately with other steps or at least a part of the sub-steps or stages of other steps.

[0119] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0120] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for designing a mask pattern, characterized in that: include: Get the main graphic; Design a variety of different auxiliary graphics based on different auxiliary graphic rules; Based on symmetry, the edge of the main figure is classified to obtain at least one pair of symmetrical regions, wherein the two symmetrical regions of the same pair are both located outside the main figure and are centrally symmetrically distributed around the center of the main figure; Different auxiliary graphics are respectively arranged in the two symmetrical regions of the same pair; The main pattern and the auxiliary pattern located in the symmetric area are combined and output to obtain a mask pattern.

2. The method for designing a mask pattern according to claim 1, characterized in that: The obtaining of the main pattern includes: designing a plurality of parallel and spaced line patterns as the main pattern; The two symmetrical areas of the same pair are respectively located on two opposite sides of the main figure.

3. The method for designing a mask pattern according to claim 1, characterized in that: The obtaining of the main pattern includes: designing a plurality of contact hole patterns arranged in an array as the main pattern; The two symmetrical regions of the same pair are respectively located at opposite sides of the main figure and / or at opposite vertex corners of the main figure.

4. The method for designing a mask pattern according to any one of claims 1 to 3, characterized in that: Each of the auxiliary graphics includes a plurality of sub-auxiliary graphics arranged at intervals; among different auxiliary graphics, at least one of the width of the sub-auxiliary graphics, the number of the sub-auxiliary graphics, the spacing between adjacent sub-auxiliary graphics, and the spacing between the auxiliary graphics and the main graphics is different from each other.

5. A method for making a photomask, characterized in that: The photomask comprises an OPC test photomask, and the method for manufacturing the photomask comprises: designing the photomask pattern by using the method for designing a photomask pattern according to any one of claims 1 to 4.

6. The method for manufacturing a photomask according to claim 5, characterized in that: Also includes: Providing a light-transmitting substrate, wherein the light-transmitting substrate is covered with a light-shielding layer; The light shielding layer is patterned based on the mask pattern, and the mask pattern is transferred to the light-transmitting substrate to obtain the mask.

7. A photomask, characterized in that: The photomask includes an OPC test photomask, the photomask includes a photomask pattern, and the photomask pattern includes: A main figure, wherein the outer side of the main figure has at least one pair of symmetrical regions, and the two symmetrical regions of the same pair are both located outside the main figure and are centrally symmetrically distributed with respect to the center of the main figure; A plurality of different auxiliary graphics are respectively located in the symmetrical regions, and the auxiliary graphics in the two symmetrical regions of the same pair are different from each other.

8. The photomask according to claim 7, wherein: The main figure includes a plurality of line figures arranged in parallel and at intervals; the two symmetrical areas of the same pair are respectively located on two opposite sides of the main figure.

9. The photomask according to claim 7, wherein: The main pattern includes a plurality of contact hole patterns arranged in an array; the two symmetrical regions of the same pair are respectively located at opposite sides of the main pattern and / or at opposite vertices of the main pattern.

10. The light mask according to any one of claims 7 to 9, characterized in that: Each of the auxiliary graphics includes a plurality of sub-auxiliary graphics arranged at intervals; among different auxiliary graphics, at least one of the width of the sub-auxiliary graphics, the number of the sub-auxiliary graphics, the spacing between adjacent sub-auxiliary graphics, and the spacing between the auxiliary graphics and the main graphics is different from each other.

Images