Preparation method of binary photomask and binary photomask

Abstract

The invention provides a preparation method of a binary photomask and the binary photomask, and the method comprises the steps: carrying out the exposure on the binary photomask through employing a low-order electron beam and laser combination mode according to the line width precision range of a design pattern; different technological processes are matched after low-order electron beam exposure and laser exposure respectively; and manufacturing a photomask with a required pattern on the binary photomask. Different exposure modes are used for combined exposure, different technological processes are matched, photoetching equipment does not need to be changed, the pattern design quality and CD precision of different areas can be effectively guaranteed, the production efficiency is improved, and therefore pattern transfer on the photomask is smoothly completed; namely, manufacturing processes such as photoetching of the photomask are realized based on the existing process equipment, so that the manufacturing efficiency and yield of the photomask are improved, and the production cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuit photomask manufacturing, and in particular, to a method for preparing a binary photomask and a binary photomask. Background Art

[0002] As integrated circuit chips become more sophisticated, higher and higher requirements are placed on photomasks. Traditional production processes cannot meet these requirements.

[0003] If high-end electron beam lithography is used, its production capacity will be seriously wasted, that is, it cannot meet the requirements of low-precision graphic design. For example, if the range of graphic design varies greatly, high-end electron beam lithography cannot meet this requirement.

[0004] Therefore, a new solution for binary photomask is needed. Summary of the invention

[0005] In view of this, embodiments of the present disclosure provide a method for preparing a binary photomask and a binary photomask.

[0006] The embodiments of this specification provide the following technical solutions:

[0007] The embodiment of the present specification provides a method for preparing a binary photomask, comprising:

[0008] According to the design pattern line width accuracy range, low-order electron beam and laser combination are used to expose on a binary photomask;

[0009] Different process flows are used after low-level electron beam exposure and laser exposure respectively;

[0010] A photomask with a desired pattern is made on the binary photomask.

[0011] The embodiment of this specification provides a binary photomask, and a photomask that meets the requirements is obtained by applying the method for preparing the binary photomask as described in the above scheme;

[0012] Among them, line widths of different precisions are arranged in this photomask, the main graphic area is set as the first precision graphic area, and the other areas are the second precision graphic areas. The first precision is higher than the second precision. The range of the first precision includes 1.4-2um, and the range of the second precision includes greater than 1.4um.

[0013] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0014] The embodiments of this specification use different exposure methods for combined exposure and match different process flows without changing the lithography equipment. This can effectively ensure the graphic design quality and CD accuracy of different areas and improve production efficiency, thereby smoothly completing the graphic transfer on the photomask. That is, based on the existing process equipment, the photolithography and other manufacturing processes of the photomask are realized, thereby improving the efficiency and yield of photomask manufacturing and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be 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 paying creative work.

[0016] Figure 1 It is a flow chart of binary photomask production in the prior art;

[0017] Figure 2 It is a flow chart of preparing a binary photomask of the present application;

[0018] Figure 3 It is a schematic diagram of low-order electron beam lithography CD linearity;

[0019] Figure 4 It is a schematic diagram of the CD linearity of the laser lithography machine;

[0020] Figure 5 The present application provides a process for preparing a binary photomask. Figure 1 ;

[0021] Figure 6 The present application provides a process for preparing a binary photomask. Figure 2 ;

[0022] Figure 7 The present application provides a process for preparing a binary photomask. Figure 3 ;

[0023] Figure 8 It is a schematic diagram of the application using a low-order electron beam with a laser lithography machine CD linear;

[0024] Fig. 9 It is a schematic diagram of a binary photomask provided in an embodiment of this specification. DETAILED DESCRIPTION

[0025] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0026] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0027] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0028] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0029] Additionally, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, it will be understood by those skilled in the art that the examples can be practiced without these specific details.

[0030] Binary photomask manufacturing process Figure 1 As shown, after the photoresist on the surface of the quartz substrate is exposed to light, the chemical properties of the photoresist change. After the development process, the designed photomask pattern is transferred to the quartz substrate through an etching process, and then the remaining photoresist is cleaned off to obtain the target photomask pattern. After that, it is necessary to measure the critical dimensions and overlay accuracy of the pattern, and inspect and repair the completed photomask pattern.

[0031] However, as integrated circuits become more sophisticated, the use of Figure 1The fixed process shown cannot meet the requirements of chip manufacturing, that is, higher requirements are put forward for the chip customers of photomask factories.

[0032] For example, more and more chip customers have put forward the design requirements of "all-in-one" special photomasks, and the traditional method cannot meet the "all-in-one" production. If high-end electron beam lithography is used blindly, its production capacity will be seriously wasted because the graphic design accuracy requirements are relatively low. For example, the graphic design range varies widely (CD requires the line width of tens of nanometers to several microns to be controlled within the target value range), and the use of high-end electron beam lithography cannot meet this requirement. Among them, "all-in-one" means that the customer's multiple photomask design graphics are combined into one photomask. The design graphics span multiple line widths of different sizes, and it is necessary to ensure that Dark and Clear simultaneously achieve high line width accuracy. Normal processes are generally difficult to control its line width performance, which can easily cause scrapping.

[0033] With the development of semiconductor manufacturing technology, more and more high-tech and sophisticated technologies and equipment are born to meet different production needs. That is, there are many kinds of existing traditional manufacturing technologies. However, the inventors found that in the face of high requirements for chip manufacturing, the field often focuses on continuing to pursue newer technologies to solve the problem in a one-shot way. However, through experimental research, the inventors hope to solve the special "all-in-one" requirements by combining different traditional existing production methods.

[0034] Based on this, the embodiment of this specification proposes a new binary photomask solution. By using different exposure methods for combined exposure and matching different process flows, there is no need to change the lithography equipment. It can effectively ensure the graphic design quality and CD accuracy of different areas and improve production efficiency, thereby smoothly completing the graphic transfer on the photomask.

[0035] The technical solutions provided by various embodiments of the present application are described below in conjunction with the accompanying drawings.

[0036] like Figure 2 As shown, a method for preparing a binary photomask provided in an embodiment of the present specification includes steps S201 to S203. In step S201, the basic design pattern line width accuracy range is exposed on the binary photomask using a combination of low-order electron beam and laser; step S202, different process flows are matched after low-order electron beam exposure and laser exposure respectively; step S203, a photomask of the desired pattern is made on the binary photomask.

[0037] The inventors found that the high-demand layout design of chip factories involves different Clear / Dark conditions, and it is necessary to ensure the CD and accuracy of graphics within the linear range of 0.42-6um. Using low-order electron beam lithography alone can ensure the quality of all graphics, but it cannot ensure the CD accuracy of graphics above 2um due to linearity; using only laser lithography cannot ensure the quality of graphics below 0.6um (laser lithography combined with wet and dry etching processes cannot meet this requirement), and it is also impossible to ensure the CD accuracy of the entire version through process adjustment due to linearity.

[0038] In step S201, low-order electron beam lithography and laser lithography are used to achieve their respective precision requirements. The inventors found that changing the order of low-order electron beam lithography and laser lithography, or using low-order electron beam lithography and laser lithography respectively in the face of "all-in-one" binary photomasks for exposure and subsequent etching for different design graphics, can preliminarily ensure that the "all-in-one" Dark and Clear can achieve higher line width accuracy at the same time.

[0039] In some embodiments, multiple photomasks may be used to manufacture the chip if required.

[0040] In some other embodiments, multiple photomask design patterns are merged into one photomask.

[0041] In step S202, the inventors found through research that after low-level electron beam exposure and laser exposure, different subsequent process flows can be used to continue to ensure a better line shape, thereby achieving better CD control for the entire plate. The inventors respectively use baking, developing, dry / wet etching processes, etc. after low-level electron beam exposure and laser exposure to achieve better CD control for the entire plate.

[0042] After the etching is completed in step S203, the photoresist is removed, CD is measured and subsequent processes are performed so that a photomask with a desired pattern can be manufactured on the binary photomask.

[0043] The embodiments of this specification use different photomask exposure modes to combine exposure and different etching processes without changing the lithography equipment, effectively ensuring the graphic design quality and CD accuracy of different areas and improving production efficiency, including low-order electron beam lithography + dry etching process + laser lithography + wet etching process, low-order electron beam lithography + dry etching process + laser lithography + dry etching process, low-order electron beam lithography + laser lithography (machine alignment) + dry etching process, a total of three methods for preparing binary photomasks.

[0044] In some embodiments, a combination of low-order electron beam and laser exposure is used for exposure, including: low-order electron beam exposure precedes laser exposure.

[0045] Specifically, Figure 3 and Figure 4 As shown, the inventors found that the CD linearity characteristics of low-order electron beam lithography and the CD linearity characteristics of laser lithography, and for the linearity characteristics corresponding to the above different lithography methods, through research, the inventors found that first performing low-order electron beam exposure and then laser exposure can form the following Figure 8 As shown, the CD linearity characteristics that meet all linearity characteristics, such as low-order electron beam lithography is suitable for sizes less than or equal to 1.4 μm, and laser lithography is suitable for sizes greater than 1.4 μm. Therefore, the inventor designs the order of low-order electron beam exposure to precede the order of laser exposure.

[0046] In some embodiments, a low-order electron beam is used to expose the first precision pattern area, and a laser is used to expose the second precision pattern area.

[0047] In the prior art of high-precision chip manufacturing, more layers of masks are used to expose the wafer to ensure the accuracy of the graphics to ensure the accuracy of the chip products. However, in the specific process, the accuracy is easily lowered due to the conversion of different masks.

[0048] In combination with the above embodiments, the inventors have found that the CD accuracy on all linearity corresponding patterns can be met by using a combination of low-order electron beam and laser for exposure.

[0049] Therefore, the inventors will satisfy the characteristic of CD accuracy on all linearity corresponding graphics. The research found that unifying the design graphics on the multi-layer masks into one photomask can not only ensure the accuracy of CDs with different line widths, but also reduce the errors caused by multiple mask conversions and overlay alignment during the chip manufacturing process, thereby improving the accuracy and effectiveness of chip manufacturing.

[0050] Specifically, the inventor studied setting different precision graphic areas into different areas according to different precisions, and designed the first precision graphic area with a range of 0.2-1.4um, and the second precision graphic area with a range of more than 1.4um. The same area can be divided into multiple shots for exposure. Combining the combination of low-order electron beam and laser, the low-order beam exposure has higher precision requirements, and the precision range is 0.2-1.4um. The laser exposure has lower precision, and the precision range is more than 1.4um. That is, the first precision is higher than the second precision.

[0051] It should be noted that by adjusting the parameter settings of the low-level electron beam and laser exposure machines, both types of lithography can simultaneously meet the needs of 1.4-2um pattern production. The new combination of low-level electron beam exposure and laser exposure can expand laser exposure to 0.7um. (See the following description for details)

[0052] In some embodiments, the post-low-level electron beam exposure process includes baking, developing, dry etching, photoresist removal, photoresist coating, etc.

[0053] In some embodiments, the process flow after laser exposure includes: development, wet etching process; or, development, dry etching process, or, baking, development, dry etching process.

[0054] Specifically, according to different design patterns, different process flows are respectively matched after low-level electron beam exposure or laser exposure to complete the photolithography process.

[0055] In some embodiments, low-level electron beam exposure, baking, development, dry etching process, photoresist removal, photoresist coating, laser exposure, development, wet etching process, photoresist removal, CD measurement, and back-end process are used, such as Figure 5 shown.

[0056] Specifically, in Scheme 1, the process route of electron beam lithography uses FEP series photoresists, which are chemically amplified photoresists (CAR), and laser exposure uses self-coating IP series photoresists (conventional Iline and G line photoresists). In traditional binary mask manufacturing, only one type of photoresist is used with one type of exposure, and the product is prepared in a single process. The 0.42-6um precision control requirement in the example cannot be achieved.

[0057] This solution is to first use electron beam exposure + dry method to complete the processing of small-size design graphics less than or equal to 1.4; then use laser lithography + wet method to complete the processing of the remaining large-size graphics greater than 1.4um. Advantages: This solution eliminates the impact of linearity in single machine production and meets the requirements for line width precision control of small-size to large-size graphics of products; both dry and wet routes are normal mass production process routes, and no process changes are required; it saves about 2 / 3 of the lithography time of electron beam lithography, and the second wet method graphic production process is shorter, occupying a lower production capacity of this route, releasing bottleneck production capacity while meeting product production needs.

[0058] In some embodiments, low-level electron beam exposure, baking, development, dry etching process, photoresist removal, photoresist coating, laser exposure, development, dry etching process, photoresist removal, CD measurement, and back-end process are used, such as Figure 6 shown.

[0059] Specifically, in the process route of scheme 2, the electron beam lithography uses FEP series photoresist, which is chemically amplified photoresist (CAR), and the self-coating IP series photoresist (conventional I line, G line photoresist) is used for laser exposure. After the IP photoresist is exposed by laser, a baking process is added, and dry etching is used to prepare the product after development. This method can significantly improve the quality and precision of small line width lines. Traditional binary masks only use one type of photoresist to complete product preparation, and the preparation of traditional IP series photoresist products generally uses wet process technology, and very few use laser 3-4pass lithography followed by dry etching technology. In this scheme, the inventor found that by improving the line quality process limit can be expanded to 0.7um, that is, the laser exposure of scheme 2 can be expanded to greater than or equal to 0.7um. Advantages: This solution eliminates the impact of linearity produced by a single machine and meets the requirements for line width accuracy control of small to large-size graphics. This process route uses laser 1pass exposure combined with baking and dry etching to break through the existing process limits and improve line quality (the process limit can also be expanded to 0.7um, and the diversified mask manufacturing process selection window is wider). The baking process after IP photoresist exposure is added, saving 2-3 times the laser exposure time.

[0060] In some embodiments, low-level electron beam exposure, laser exposure, baking, development, dry etching, photoresist removal, CD measurement, and back-end process are used, such as Figure 7 shown.

[0061] Specifically, in Scheme 3, both the electron beam and laser lithography use FEP series photoresists. The wavelength of the laser (DUV) lithography light source used here is 266nm, which is different from the type of light source used in the above laser lithography. The product is prepared in combination with normal baking, developing, and dry etching. The difference between this route and the traditional process route is that under the normal process route, one laser exposure is added, and laser lithography and Alignment functions are required to complete the laser graphic exposure. Advantages: This solution eliminates the influence of linearity in single-machine production and meets the requirements for line width precision control of small to large-size graphics of products; saves electron beam exposure time and only adds one laser exposure. Using mass production process technology, no process changes are required, and only one process is required to complete product production, saving production costs.

[0062] If the customer can achieve free precision alignment with a single shot (a single photolithography exposure process in one field), that is, using two consecutive exposures: low-order electron beam exposure and laser exposure, combined with different process flows.

[0063] It should be noted that if only rough alignment is performed by laser lithography, the overlay accuracy deviation will exceed the card control range. Therefore, the second continuous exposure is suitable for fine alignment of each independent spliced ​​chip after the laser lithography machine completes the rough alignment, so that the application can ensure that the overlay accuracy is within the card control range).

[0064] Therefore, low-order electron beam exposure is suitable for design graphics with a line width of less than or equal to 1.4μm, and laser exposure is suitable for design graphics with a size greater than 1.4μm (method 2 can be expanded to 0.7um). Then, according to different graphic designs, different process flows, such as wet etching or dry etching process flows, are used to achieve graphic quality and CD accuracy.

[0065] Through the above three methods, different processes can be matched according to different designs to ensure the quality of graphics, and can ensure better linearity and achieve better CD control for the entire page. Figure 8 As shown, the electron beam lithography pattern area is reduced, the pattern transfer on the photomask is successfully completed, the lithography time is saved by about 4 hours, and the machine utilization rate is improved. The photomask lithography and other manufacturing processes are realized based on the existing process equipment, which increases order revenue, improves the manufacturing efficiency and yield of photomask manufacturing, and reduces production costs.

[0066] In some embodiments, the line width of the pattern in the photomask ranges from 0.42 μm to 6 μm.

[0067] In some embodiments, the line width of a pattern in a photomask ranges from 0.42 μm to 6 μm.

[0068] This application combines different exposure methods with different process flows, including low-level electron beam lithography + dry etching process + laser lithography + wet etching process, low-level electron beam lithography + dry etching process + laser lithography + dry etching process, and low-level electron beam lithography + laser lithography (machine alignment) + dry etching process, a total of three methods to prepare Binary photomasks. There is no need to change the lithography equipment, effectively guarantee the quality of graphic design in different areas and its CD accuracy, improve production efficiency, and successfully complete the graphic transfer on the photomask, that is, based on the existing process equipment to realize the lithography and other manufacturing processes of the photomask, improve the manufacturing efficiency and yield of the photomask manufacturing, and reduce production costs.

[0069] In combination with the above-mentioned embodiment, the method for preparing a binary photomask obtains a photomask that meets the requirements; wherein, in the photomask, line widths of different precisions are arranged, wherein the main graphic area is set with a graphic of the first precision, and other areas are set with a graphic of the second precision of >1.4um, and the first precision is higher than the second precision. The range of the first precision is, for example, 0.2-1.4um. The range of the second precision is, for example, greater than 1.4um.

[0070] Specifically, Fig. 9 As shown, the corresponding patterns of different layers on the chip end are set as a photomask to meet the higher refinement of integrated circuit manufacturing. The double exposure function is used for two times of photolithography. Different process flows are matched according to different pattern designs, and the preparation of the binary photomask is completed in combination with the subsequent process flows. Fig. 9 The example has a total of 6 layers of different graphics, which traditionally require the use of 6 masks, but this application can merge them into one mask.

[0071] In some embodiments, a first precision pattern is set in the main pattern area on a photomask, and a second precision pattern is set in other pattern areas, and the first precision is higher than the second precision. The 1.4-2um area can freely choose the type of exposure machine. It should be noted that the laser exposure in the second solution can be expanded to ≥0.7um.

[0072] The first precision and the second precision may represent specific precision numerical points or appropriate precision ranges respectively. In either case, the first precision is still higher than the second precision.

[0073] In some embodiments, a method for preparing a binary photomask is combined to first expose the main graphic area using a low-order electron beam, and then expose other graphic areas using a laser. The photomask's lithography and other manufacturing processes are implemented based on existing process equipment to improve the manufacturing efficiency and yield of the photomask manufacturing and reduce production costs.

[0074] This application can eliminate the CD over-spec situation caused by linear effects by combining different photomask exposure methods with different etching processes without changing the photolithography equipment. While reducing the scrap rate, it can ensure the quality of various line width design graphics. It saves the production capacity of electron beam lithography machines, realizes photolithography and other manufacturing processes of photomasks based on existing process equipment, improves the manufacturing efficiency and yield of photomask manufacturing, and reduces production costs.

[0075] The present invention proposes an improved binary photomask manufacturing method, which has the following characteristics: pattern transfer is achieved by combining different photomask exposure modes and matching different process flows without any modification to the lithography equipment.

[0076] This method can eliminate the problem of CD precision exceeding the standard caused by linear influence, reduce the scrap rate, and ensure the quality of various design graphics with different line widths.

[0077] This method can save the production capacity of high-end electron beam lithography equipment and improve production efficiency.

[0078] This invention is based on existing process equipment, improves the efficiency and yield of photomask manufacturing, and reduces production costs.

[0079] Specifically, this approach achieves its goals through the following measures:

[0080] Combine different photomask exposure methods: Use different exposure methods to make up for the shortcomings of a single method. For example, define different exposure areas for different machines according to different line width designs.

[0081] Match different process flows: Select appropriate process flows according to different pattern designs and process requirements, for example, using different etching methods.

[0082] The advantages of this method are:

[0083] No modification of the lithography equipment is required: existing equipment can be used for production, saving the cost of equipment upgrades.

[0084] Eliminate the problem of excessive CD precision caused by excessive linear difference range: improve the accuracy and reliability of photomask.

[0085] Reduce scrap rate: improve production yield and reduce production costs.

[0086] Ensure the quality of various design graphics with different line widths: meet the manufacturing needs of different products.

[0087] Save high-end electron beam machine capacity and improve production efficiency: improve production efficiency and reduce production costs.

[0088] In summary, the present application provides an efficient, economical and reliable binary photomask manufacturing method, which realizes photolithography and other manufacturing processes of photomasks based on existing process equipment, increases order revenue, improves the manufacturing efficiency and yield of photomask manufacturing, optimizes the production process, and reduces production costs. It can significantly improve the efficiency and yield of photomask manufacturing and has important application value.

[0089] The process descriptions in the accompanying drawings are as follows:

[0090] Exposure: Exposure; Develop: Development; Etch: Etching; CD Measure: Key Dimension Measurement; Strip: Removal of Photoresist; Registration: Registration Difference Measurement; Bef-Inspect: Pre-process Inspection; Repair: Repair; AMIS: AMIS Parameters; Clean / Mount: Cleaning / Packaging; Aft-Inspect: Post-process Inspection; Pack / Shipping: Packing / Transportation; Coat: Coating.

[0091] The same or similar parts between the various embodiments in this specification can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the product embodiment described later, since it corresponds to the method, the description is relatively simple, and the relevant parts can be referred to the partial description of the system embodiment.

[0092] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for preparing a binary photomask, characterized in that: include: According to the design pattern line width accuracy range, low-order electron beam and laser combination are used to expose on a binary photomask; Different process flows are used after low-level electron beam exposure and laser exposure respectively; A photomask with a desired pattern is made on the binary photomask.

2. The method for preparing a binary photomask according to claim 1, characterized in that: Exposure is performed using a combination of low-level electron beam and laser, including: The sequence of low-level electron beam exposure precedes the laser exposure.

3. The method for preparing a binary photomask according to claim 1, characterized in that: The first precision pattern area is exposed by low-order electron beam, and the second precision pattern area is exposed by laser.

4. The method for preparing a binary photomask according to claim 1, characterized in that: The process flow after low-level electron beam exposure includes: Baking, developing, dry etching process, photoresist removal, photoresist coating.

5. The method for preparing a binary photomask according to claim 1, characterized in that: The process flow after laser exposure includes: Development and wet etching processes; or, developing and dry etching process; Or, baking, developing, and dry etching processes.

6. The method for preparing a binary photomask according to any one of claims 1 to 5, characterized in that: Use low-level electron beam exposure, baking, development, dry etching process, remove photoresist, apply photoresist, use laser exposure, development, wet etching process, remove photoresist, CD measurement, and post-processing.

7. The method for preparing a binary photomask according to any one of claims 1 to 5, characterized in that: Use low-level electron beam exposure, baking, development, dry etching process, remove photoresist, apply photoresist, use laser exposure, development, dry etching process, remove photoresist, CD measurement, and post-processing.

8. The method for preparing a binary photomask according to any one of claims 1 to 5, characterized in that: It uses low-level electron beam exposure, laser exposure, baking, development, dry etching process, photoresist removal, CD measurement, and post-processing.

9. The method for preparing a binary photomask according to claim 1, characterized in that: The line width of the pattern in the photomask ranges from 0.42 μm to 6 μm.

10. A binary photomask, characterized in that: Applying the method for preparing a binary photomask as described in claims 1 to 9 to obtain a photomask that meets the requirements; Among them, line widths of different precisions are arranged in this photomask, the main graphic area is set as the first precision graphic area, and other areas are set as the second precision graphic area. The first precision is higher than the second precision. The range of the first precision includes 0.2-1.4um, and the range of the second precision includes greater than 1.4μm.

Images