High-resolution mask and preparation method thereof

Abstract

The invention relates to the technical field of mask manufacturing, in particular to a high-resolution mask and a preparation method thereof. Comprising the steps that a template is prepared, the template comprises a first substrate, the surface of the first substrate is provided with a first pattern, and an anti-sticking layer is formed on the first substrate; preparing a second substrate, and forming a tackifying layer on the second substrate; after imprinting glue is sprayed on the surface of the first substrate, imprinting exposure is carried out on the template and the second substrate, and after the imprinting glue is cured, demolding treatment is carried out, so that the imprinting glue forms an imprinting glue layer with a second pattern on the surface of the second substrate; the second graph and the first graph are complementary; and etching and transmitting the second pattern to the surface of the second substrate to obtain the high-resolution mask plate. Compared with a traditional direct writing type photoetching mode and the like, the manufacturing cost of the high-resolution mask is remarkably reduced, and meanwhile the machining efficiency of the high-resolution mask is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mask manufacturing, in particular to a high-resolution mask and a preparation method thereof. BACKGROUND

[0002] A photomask is a key component in microelectronic manufacturing, especially in integrated circuit manufacturing, which functions like a "negative" of a camera, used to accurately transfer designed patterns to a semiconductor wafer in a photolithography process. The precision, quality and preparation efficiency of a mask directly determine the feature size, performance and manufacturing cost of the final integrated circuit.

[0003] Currently, the mainstream method for preparing high-precision masks in the industry mainly includes electron beam direct writing (EBL) and laser direct writing (LDW) technologies. However, as the semiconductor technology node continues to evolve, the requirement for mask pattern resolution has approached the physical limit (e.g., 100 nm and below period), and the drawbacks of existing traditional technologies in terms of efficiency, cost and complexity are increasingly prominent.

[0004] Electron beam direct writing is currently the core technology for preparing high-resolution masks. Its process flow is usually as follows: a photoresist is coated on a mask substrate plated with a chromium layer, a focused high-energy electron beam is used to scan and expose the photoresist according to the design pattern, changing the solubility characteristics of the exposed area of the photoresist; then the exposed or unexposed area is dissolved by a developing solution to form a patterned photoresist mask; finally, through an etching process, the pattern is transferred from the photoresist layer to the chromium layer below, thereby completing the preparation of the mask. Although electron beam direct writing technology has extremely high resolution, up to nanometer level, it has the following fundamental defects that are difficult to overcome: low writing efficiency, low throughput, high preparation cost, proximity effect and low device life caused by device wear.

[0005] Laser direct writing technology uses a focused laser beam to replace the electron beam for scanning exposure, and its process flow is similar to that of electron beam direct writing. Although it has certain advantages in writing speed and cost compared to electron beam, its inherent defects limit its application in the field of high-precision mask preparation: limited resolution, poor pattern edge roughness, and difficulty in meeting the high-precision requirements of advanced technology nodes for mask line profiles.

[0006] In summary, the existing mask preparation technology has outstanding contradictions, that is, high resolution (such as electron beam direct writing) and high throughput, low cost cannot be achieved. Although electron beam direct writing can meet the pattern resolution requirements of modern semiconductor high-precision technology nodes (such as 100 nm period and below), it is time-consuming, high cost and complex calculation. As another common way of preparing masks, laser direct writing has higher processing efficiency and lower cost; although the efficiency is improved, it cannot meet the extremely high resolution requirement. Since laser direct writing uses focused laser beams to perform micro-nano processing on the material surface, it cannot break through the wavelength resolution limit, resulting in that the micro-nano structure prepared by laser direct writing is generally micron-level, and high-resolution (nanometer-level) masks cannot be processed.

[0007] Therefore, it is of great significance to develop a new mask preparation process to achieve high resolution, high throughput and low cost at the same time, and to complete the batch preparation of multiple high-resolution masks in a short time, which can break through the bottleneck of advanced semiconductor manufacturing and reduce the cost of research and production. It is also an urgent need and important direction of current research and technical development in this field. SUMMARY

[0008] (1) Technical problems to be solved The purpose of the present application is to overcome the problems of high cost and long time consumption in the preparation of high-resolution masks in the prior art, which affects the efficiency of semiconductor production. At the same time, because high-resolution masks rely on high-precision equipment such as electron beam direct writing photolithography machine, it leads to the technical deficiency of difficult mask processing. The present application provides a high-resolution mask, a preparation method and a batch preparation method.

[0009] (2) Technical solutions In a first aspect, the present application provides a preparation method of a high-resolution mask, comprising the following preparation steps: S1, preparing a mask, the mask comprising a first substrate, the first substrate surface having a first pattern, and an anti-adhesion layer formed on the first substrate; S2, preparing a second substrate, and forming an adhesion-enhancing layer on the second substrate; S3, after spraying a stamping glue on the surface of the first substrate, the mask and the second substrate are subjected to stamping exposure, and after the stamping glue is cured, the stamping glue is removed to form a stamping glue layer with a second pattern on the surface of the second substrate; the second pattern is complementary to the first pattern; S4, etching the second pattern to the surface of the second substrate to obtain a high-resolution mask.

[0010] Preferably, in step S1, the mask is prepared according to the following steps: S1.1: preparing a photosensitive film layer on the first substrate, the thickness of the photosensitive film layer being 10-150 nm; S1.2: exposing and developing the photosensitive film layer to form a photoetching pattern, and removing the photosensitive film layer; S1.3: transferring the photoetching pattern to the first substrate surface by etching to obtain a template with a first pattern.

[0011] Preferably, the first substrate is any one of a silicon substrate, a quartz substrate, and a flexible substrate, and the thickness of the first substrate is 0.7-1.5 mm.

[0012] Preferably, the material of the photosensitive film layer is photoresist, and the type of the photoresist includes any one of AR series photoresist, AZ series photoresist, photosensitive material with 365 nm wavelength, and electron beam photoresist, and the photosensitive film layer is arranged on the first substrate by spin coating or fumigation.

[0013] Preferably, the thickness of the anti-sticking layer is not more than 2 nm.

[0014] Further preferably, the anti-sticking layer is prepared by spin coating or fumigation of an anti-sticking solution on the surface of the first substrate to form the anti-sticking layer, and the main active ingredient of the anti-sticking solution is perfluorooctylsilane.

[0015] Preferably, the tackifying layer is prepared by spin coating or fumigation of a tackifying solution on the second substrate to form the tackifying layer, the thickness of the tackifying layer is not more than 2 nm, and the main active ingredient of the tackifying solution is hexamethyldisilazane.

[0016] Preferably, the drop spraying interval of the imprint glue is 280-630 μm, and in step S3, the imprint glue layer includes an upper layer second pattern and a lower layer residual glue layer, and the structure depth of the second pattern is at least 1.5 times the thickness of the residual glue layer.

[0017] Preferably, the method further comprises: Step S5: repeating steps S2-S4 to complete the preparation of a plurality of high-resolution mask templates.

[0018] In a third aspect, the application provides a high-resolution mask template prepared according to the method for preparing a high-resolution mask template.

[0019] (Three) beneficial effects The application provides an innovative mask template preparation process: first, a high-precision mask pattern is prepared on the template surface, and then the pattern is transferred to the mask template substrate by imprint technology. The core advantage of this process is to first prepare a pattern template and to realize efficient and high-fidelity replication of the pattern by using imprint technology. Compared with traditional direct writing photolithography and other methods, the imprint method greatly shortens the patterning time and significantly improves the preparation efficiency of the mask template.

[0020] In addition, the method has good scalability and repeatability. Once the graphic template with high-resolution pattern is prepared, multiple identical precision mask templates can be quickly copied by multiple times of imprinting, greatly reducing the preparation period and single-piece cost of high-resolution mask templates. This not only speeds up the research and development iteration of high-end semiconductor devices, but also provides a reliable technical path for rapid replacement and backup of mask templates in mass production.

[0021] Therefore, the present application not only improves the manufacturing efficiency of the mask template, but also forms a repeatable pattern transfer technology route with silicon substrate, quartz substrate and flexible substrate as the graphic source, providing a stable and scalable process foundation for the preparation of higher resolution and more complex structure masks in the future. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 A flowchart of the preparation method of the high-resolution mask template according to an embodiment of the present disclosure is schematically shown; Figure 2 A structural schematic diagram of the template according to an embodiment of the present disclosure is schematically shown; Figure 3 A process variation diagram of the template preparation according to an embodiment of the present disclosure is schematically shown; Figure 4 A schematic diagram of the ultraviolet imprinting step according to an embodiment of the present disclosure is schematically shown; Figure 5 A schematic diagram of the second substrate after the demolding process according to an embodiment of the present disclosure is schematically shown; Figure 6 A structural schematic diagram of the high-resolution mask template according to an embodiment of the present disclosure is schematically shown; Figure 7 SEM images of different test patterns of Example 1 according to an embodiment of the present disclosure are schematically shown; Figure 8 A line grid pattern SEM image of Example 1 according to an embodiment of the present disclosure is schematically shown; Figure 9 A line grid pattern SEM image of Example 2 according to an embodiment of the present disclosure is schematically shown; Figure 10 A line grid pattern SEM image of Example 3 according to an embodiment of the present disclosure is schematically shown.

[0023] Explanation of reference numerals: 1 - first substrate; 2 - first pattern; 3 - photosensitive film layer; 4 - second substrate; 5 - imprinting glue layer; 51 - second pattern; 52 - remaining residual glue layer. DETAILED DESCRIPTION

[0024] The application will be further described in connection with the following specific embodiments. However, it should be understood that the scope of the subject matter of the application is not limited to the following embodiments, and any technology implemented based on the content of the application falls within the scope of the application.

[0025] Embodiments of the present disclosure provide a preparation method of high-resolution mask, which combines Figure 1 The preparation method can be understood by the following flow chart, and includes the following steps: Step S1: preparing a template, the template including a first substrate 1, the first substrate 1 having a first pattern 2 on the surface, and an anti-adhesion layer formed on the first substrate 1; Specifically, the template is prepared according to the following steps: S1.1: preparing a photosensitive film layer 3 on the first substrate, the thickness of the photosensitive film layer 3 being 10-150 nm; The material of the photosensitive film layer 3 is photoresist, and the type of the photoresist includes any one of AR series photoresist, AZ series photoresist, 365 nm wavelength photosensitive material, and electron beam glue. The photosensitive film layer 3 is arranged on the first substrate by spin coating or fumigation.

[0026] The first substrate 1 can be any one of a silicon substrate, a quartz substrate, and a flexible substrate, and the thickness of the first substrate is 0.7-1.5 mm.

[0027] S1.2: exposing and developing the photosensitive film layer 3 to form a photoetching pattern, and removing the photosensitive film layer; S1.3: transferring the photoetching pattern to the surface of the first substrate by etching to obtain a template having the first pattern.

[0028] Specifically, in step S1.2, the exposure and development include 365 nm projection photoetching, electron beam direct writing photoetching, or SP super-resolution photoetching. The photosensitive film layer can be soaked in a developing solution for development, or the developing solution can be sprayed onto the surface of the photosensitive film layer for development. The developing solution can be AR series photoresist, AZ series photoresist, or other ultraviolet series photoresist special developing solution. Then, the underlying substrate is selectively etched with the photoresist pattern as a mask, and the pattern can be etched and transferred to the first substrate by reactive ion etching (RIE) or inductively coupled plasma etching (ICP). The template is the basis for subsequent batch preparation of high-resolution mask.

[0029] S2, preparing a second substrate 4, and forming an adhesion layer on the second substrate 4; wherein the adhesion layer is prepared by spin coating or fumigation of an adhesion solution on the second substrate, the adhesion solution being a solution with hexamethyldisilazane (HMDS) as the main active ingredient. The thickness of the adhesion layer can be 2 nm.

[0030] For example, the adhesion layer can be Surpass, which is a series of adhesion products under the brand of DuPont Company.

[0031] S3, after the first substrate 1 surface is sprayed with the imprinting glue, the template is subjected to imprinting exposure with the second substrate 4, and after the imprinting glue is cured, the demolding treatment is performed to form an imprinting glue layer 5 with a second pattern on the surface of the second substrate; the second pattern 51 is complementary to the first pattern 2. The thickness of the anti-adhesion layer is not more than 2 nm, and the anti-adhesion layer is prepared by spin coating or fumigation of an anti-adhesion solution on the surface of the first substrate, the main active ingredient of the anti-adhesion solution being perfluorooctylsilane. When used, it needs to be diluted to a specific concentration range.

[0032] For example, the anti-adhesion solution can be X-71-197. X-71-197 is a commercial product produced by DuPont Company in the United States, which is a solution with perfluorooctylsilane as the main active ingredient and has been prepared. It is a ready-to-use formula, specifically a concentrate, which usually needs to be diluted for use.

[0033] The drop spacing of the imprinting glue is 280-630 μm, and the imprinting glue is an imprinting glue liquid before curing. The imprinting glue liquid is uniformly sprayed on the surface of the first pattern of the template by the spraying equipment, and the content of the imprinting glue liquid is determined by adjusting the spacing of adjacent droplets. If the spacing is too large, the imprinting glue cannot fill the imprinting area, which will cause uneven residual layer and poor etching effect; if the spacing is too small, the imprinting glue cannot flow uniformly, which will cause the formation of bubbles and uneven film layer.

[0034] In step S3, the imprinting glue layer includes an upper layer of the second pattern 51 and a lower layer of the residual glue layer 52, and the structure depth of the second pattern 51 is at least 1.5 times the thickness of the residual glue layer 52.

[0035] Step S4: etching the second pattern to the surface of the second substrate to obtain a high-resolution mask.

[0036] Step S5: repeating steps S2-S4 to complete the preparation of multiple high-resolution masks.

[0037] In the above preparation scheme, a high-precision mask pattern is first prepared on the surface of the first substrate, and then the pattern is transferred to the mask template substrate by the imprinting technology. The core advantage of this process is that the first substrate will serve as a pattern template, and the imprinting technology is used to achieve efficient and high-fidelity replication of the pattern. Compared with traditional direct writing photolithography and other methods, the imprinting method greatly shortens the patterning time and significantly improves the preparation efficiency of the mask template.

[0038] Specifically, the following four embodiments are provided: Embodiment 1: This embodiment provides a high-resolution mask template, as shown in Figure 2 The structure of the template is shown in the figure, and the upper surface of the first substrate has a first pattern. The high-resolution mask template comprises the following preparation steps: Specifically, as shown in Figure 3 S1, the template is prepared according to the following method: S1.1: A photosensitive film layer is prepared on the first substrate, and the thickness of the photosensitive film layer is 50 nm. The material of the photosensitive film layer is photoresist, and the model of the photoresist is AR series photoresist. The photosensitive film layer is disposed on the first substrate by spin coating, and the first substrate is a silicon wafer.

[0039] S1.2: The photosensitive film layer is exposed and developed to form a photoetching pattern, and the photosensitive film layer is removed. S1.3: The photoetching pattern is transferred to the surface of the first substrate by etching to obtain a template with a first pattern.

[0040] S2, a second substrate is prepared, and a tackiness layer is disposed on the second substrate. The second substrate is a quartz substrate, and the tackiness layer is disposed on the second substrate by spin coating. The tackiness layer is prepared by spin coating a tackiness solution on the second substrate to form a tackiness layer, and the tackiness solution is a solution with hexamethyl disilazane as the main active ingredient. The thickness of the tackiness layer is 2 nm.

[0041] S3, an anti-adhesion layer is prepared on the surface of the first pattern of the template, and the anti-adhesion solution is a solution with perfluorooctylsilane as the main active ingredient. Then, the template and the second substrate are matched and imprinted, and a curing treatment is performed. After curing, the template is removed to form a pressure-sensitive adhesive layer with a second pattern on the surface of the second substrate; the second pattern is complementary to the first pattern; as shown in Figures 4-5 .

[0042] The drop spraying interval of the pressure-sensitive adhesive is 280 μm. The thickness of the remaining residual adhesive layer is measured to be 52 nm, and the structure depth of the second pattern is 93 nm.

[0043] S4, the second pattern is etched and transferred to the surface of the second substrate to obtain a high-resolution mask template; as shown in Figure 6 .

[0044] Example 2: This embodiment provides a high-resolution mask, the preparation method of which is the same as in Embodiment 1, including: S1. Prepare a template, the template including a first substrate, the surface of the first substrate having a first pattern; Specifically, such as Figure 3 As shown, S1 and the template are prepared in the following manner: S1.1: A photosensitive film layer is prepared on a first substrate, the thickness of which is 50 nm; the material of the photosensitive film layer is a photosensitive material that is sensitive to a wavelength of 365 nm, and the photosensitive film layer is set on the first substrate by spin coating, the first substrate being a quartz substrate.

[0045] S1.2: Expose and develop the photosensitive film layer to form a photolithographic pattern, and then remove the photosensitive film layer; S1.3: The photolithographic pattern is transferred to the surface of the first substrate by etching to obtain a template with the first pattern.

[0046] S2. Prepare a second substrate and deposit an adhesion layer on it. The second substrate is a silicon wafer, and the adhesion layer is deposited on the second substrate by spin coating. The adhesion layer is prepared by spin coating an adhesion solution onto the second substrate, wherein the adhesion solution is a solution with hexamethyldisilazane as the main active ingredient. The thickness of the adhesion layer is 2 nm.

[0047] S3. An anti-adhesion layer is prepared on the surface of the first pattern of the template. The anti-adhesion solution is a solution with perfluorooctylsilane as the main active ingredient. Then, an imprinting adhesive is sprayed onto the surface of the first pattern of the template. The template and the second substrate are then aligned and imprinted, and cured. After curing, a demolding process is performed to form an imprinting adhesive layer with a second pattern on the surface of the second substrate. The second pattern is complementary to the first pattern. In this embodiment, the droplet spraying distance of the imprinting adhesive is 490 μm; the thickness of the remaining adhesive layer is measured to be 27 nm, and the structural depth of the second pattern is 95 nm.

[0048] S4. The second pattern is etched and transferred to the surface of the second substrate to obtain a high-resolution mask.

[0049] Example 3: This embodiment provides a high-resolution mask, the preparation method of which is the same as in Embodiment 1, including: S1. Prepare a template, the template including a first substrate, the surface of the first substrate having a first pattern; Specifically, the template is prepared in the following manner: S1.1: A photosensitive film layer is prepared on a first substrate, the thickness of which is 50 nm; the material of the photosensitive film layer is electron beam adhesive, and the photosensitive film layer is set on the first substrate by spin coating, the first substrate being a polydimethylsiloxane flexible substrate; S1.2: exposing and developing the photosensitive film layer to form a photoetching pattern, and removing the photosensitive film layer; S1.3: transferring the photoetching pattern to the surface of the first substrate by etching to obtain a template with a first pattern.

[0050] S2, preparing a second substrate and setting an adhesion-increasing layer on the second substrate; the second substrate is a silicon wafer, and the adhesion-increasing layer is set on the second substrate by spin coating; wherein the adhesion-increasing layer is prepared by spin coating an adhesion-increasing solution on the second substrate to form the adhesion-increasing layer, and the adhesion-increasing solution is a solution with hexamethyldisilazane as a main active ingredient. The thickness of the adhesion-increasing layer is 2 nm.

[0051] S3, preparing an anti-adhesion layer on the surface of the first pattern of the template, and the anti-adhesion solution is a solution with perfluorooctylsilane as a main active ingredient. Then, the template and the second substrate are matched and pressed to perform imprinting, and a curing treatment is performed. After curing, a demolding treatment is performed to form an imprinting adhesive layer with a second pattern on the surface of the second substrate; the second pattern is complementary to the first pattern. In this embodiment, the drop spraying interval of the imprinting adhesive is 630 μm; the thickness of the residual adhesive layer is measured to be 18 nm, and the structure depth of the second pattern is 92 nm.

[0052] S4, etching the second pattern to the surface of the second substrate to obtain a high-resolution mask template.

[0053] Figure 7 SEM images of different test patterns in Example 1. Including line grid, cylinder and circuit pattern. Among them, the 38 nm resolution pattern can be clearly distinguished, and the line grid, cylinder and circuit pattern are clearly distinguished without bridging and cracking defects.

[0054] Among them, Figures 8-10 respectively, SEM tests are performed on the photoetching patterns (line grid) on the mask templates obtained in Examples 1-3. As shown in the drawings, the process of the application realizes efficient and high-fidelity replication of patterns by using imprinting technology.

[0055] Example 4: This embodiment provides a high-resolution mask template, and the preparation method is the same as that of Example 1. The difference is that the drop spraying interval of this embodiment is 560 μm. And the prepared high-resolution mask template pattern quality consistency is compared repeatedly three times. The high-resolution mask templates are respectively named as substrate 1-substrate 3.

[0056] Through thickness testing of the substrates 1-3, the statistical data of Table 1 is obtained: Table 1 is a test structure summary table of substrates 1-3

[0057] From the data in Table 1, it can be seen that the mask plate prepared by the mask plate preparation method of the present application has a glue thickness deviation of not more than 1 nm, which is found by testing the photolithography pattern points of multiple regions.

[0058] The innovative mask plate preparation process of the present application prepares a high-precision mask pattern on a template surface, and then transfers the pattern to a mask plate substrate by imprinting technology. The core advantage of the process is to prepare a pattern template first, and then use imprinting technology to achieve efficient and high-fidelity replication of the pattern. Compared with traditional direct writing photolithography and other methods, the imprinting method greatly shortens the patterning time and significantly improves the preparation efficiency of the mask plate. The method has good scalability and repeatability. Once a template with a high-resolution pattern is prepared, multiple mask plates with the same precision can be quickly replicated by multiple imprinting, greatly reducing the preparation cycle and single-piece cost of high-resolution mask plates.

[0059] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a high-resolution photomask, characterized in that, The preparation steps include the following: S1. Prepare a template, the template including a first substrate, the surface of the first substrate having a first pattern, and forming an anti-adhesion layer on the first substrate; S2. Prepare a second substrate and form an adhesive layer on the second substrate; S3. After spraying imprinting adhesive onto the surface of the first substrate, the template is imprinted and exposed to the second substrate. After the imprinting adhesive is cured, a demolding process is performed to form an imprinting adhesive layer with a second pattern on the surface of the second substrate. The second shape is complementary to the first shape; S4. The second pattern is etched and transferred to the surface of the second substrate to obtain a high-resolution mask.

2. The method for preparing a high-resolution photomask according to claim 1, characterized in that, In step S1, the template is prepared according to the following steps: S1.1: A photosensitive film layer is prepared on the first substrate, wherein the thickness of the photosensitive film layer is 10-150 nm; S1.2: Expose and develop the photosensitive film layer to form a photolithographic pattern, and then remove the photosensitive film layer; S1.3: The photolithographic pattern is transferred to the surface of the first substrate by etching to obtain a template with the first pattern.

3. The method for preparing a high-resolution photomask according to claim 2, characterized in that, The first substrate is any one of silicon substrate, quartz substrate, and flexible substrate, and the thickness of the first substrate is 0.7mm-1.5mm.

4. The method for preparing a high-resolution photomask according to claim 2, characterized in that, The photosensitive film layer is made of photoresist, and the type of photoresist includes any one of AR series photoresist, AZ series photoresist, photosensitive material with a wavelength of 365nm, and electron beam photoresist. The photosensitive film layer is deposited on the first substrate by spin coating or fumigation.

5. The method for preparing a high-resolution photomask according to claim 1, characterized in that, The thickness of the anti-adhesion layer does not exceed 2 nm.

6. The method for preparing a high-resolution photomask according to claim 5, characterized in that, The anti-adhesion layer is prepared by spin-coating or fumigating an anti-adhesion solution onto the surface of the first substrate to form the anti-adhesion layer, wherein the main active ingredient of the anti-adhesion solution is perfluorooctylsilane.

7. The method for preparing a high-resolution photomask according to claim 1, characterized in that, The tackifying layer is formed by spin-coating or fumigating a tackifying solution onto the second substrate. The thickness of the tackifying layer does not exceed 2 nm. The main active ingredient of the tackifying solution is hexamethyldisilazane.

8. The method for preparing a high-resolution photomask according to claim 1, characterized in that, The droplet spraying distance of the imprinting adhesive is 280μm-630μm. In step S3, the imprinting adhesive layer includes an upper second pattern and a lower residual adhesive layer. The structural depth of the second pattern is at least 1.5 times the thickness of the residual adhesive layer.

9. The method for preparing a high-resolution photomask according to any one of claims 1-8, characterized in that, Also includes: Step S5: Repeat steps S2-S4 to complete the preparation of multiple high-resolution masks.

10. A high-resolution photomask, characterized in that, The high-resolution mask is prepared according to the method described in claim 9.

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