Photoetching medium and preparation method of micro-nano structure

Abstract

The embodiment of the invention provides a photoetching medium which is used for preparing a micro-nano structure, the micro-nano structure comprises a substrate and a pattern layer on the substrate, the pattern layer is formed by the photoetching medium, and the photoetching medium is made of thermosensitive photoresist. According to the photoetching medium provided by the embodiment of the invention, high-resolution patterning of a micro-nano structure can be realized at a nano level through application of the thermosensitive photoresist. The embodiment of the invention further provides a preparation method of the micro-nano structure.

Description

Technical Field

[0001] This application belongs to the field of micro-nano manufacturing technology, and particularly relates to a lithography medium and a preparation method of a micro-nano structure. Background Art

[0002] Thermal Scanning Probe Lithography (t-SPL) is an advanced nano-manufacturing method that achieves high-resolution patterning through local thermal energy driving. The thermal probe consists of a tip heating element. When the probe contacts the material surface, chemical or physical changes of the material are induced by local heating. The core of this technology lies in controlling the accuracy of heat transfer to ensure the microscopic size and high uniformity of the processing area.

[0003] Thermosensitive photoresist is a key material in t-SPL, and its performance directly determines the processing resolution and efficiency. The thermosensitive photoresist needs to have thermal responsiveness and high-resolution characteristics, be able to quickly react under a certain heat stimulus to form a pattern, and at the same time meet the requirements of nano-scale processing to form smooth boundaries and clear patterns. Existing photoresists are difficult to meet the above requirements. Summary of the Invention

[0004] Aiming at the problems existing in the above related technologies, the present invention provides a lithography medium and a preparation method of a micro-nano structure. Through the application of a thermosensitive photoresist, high-resolution patterning of the micro-nano structure can be achieved at the nano scale.

[0005] In a first aspect, an embodiment of the present application provides a lithography medium for preparing a micro-nano structure. The micro-nano structure includes a substrate and a pattern layer on the substrate. The pattern layer is formed by the lithography medium, and the lithography medium is made of a thermosensitive photoresist.

[0006] Further, the thermosensitive photoresist is PPC, and the lithography medium is formed by a PPC solution with a concentration of 6.5%.

[0007] Further, the PPC solution is formed by dissolving PPC solid particles in anisole solvent.

[0008] Further, the thickness of the PPC film is between 250 nm and 300 nm.

[0009] Further, the thermal decomposition temperature of the PPC film is greater than 300 °C.

[0010] In a second aspect, an embodiment of the present application provides a preparation method of a micro-nano structure, including the following steps:

[0011] Spin-coating a thermosensitive photoresist on a substrate; and

[0012] An etched hollow pattern is formed on the thermosensitive photoresist to form a pattern layer on the substrate.

[0013] Further, the thermosensitive photoresist is PPC. The spin-coating of the thermosensitive photoresist on the substrate includes:

[0014] Dropping the prepared PPC solution onto the surface of the substrate; and

[0015] Performing a spin-coating operation to form the PPC thin film on the substrate.

[0016] Further, the concentration of the PPC solution is 6.5%.

[0017] Further, the etching of the etched hollow pattern on the photoresist thin film to form a pattern layer on the substrate includes:

[0018] Etching an array pattern on the photoresist thin film through a thermal probe; and

[0019] Etching the hollow pattern on the array pattern through a plasma processing method to form the pattern layer on the substrate.

[0020] Further, the etching of the hollow pattern on the array pattern through a plasma processing method to form a pattern layer on the substrate includes:

[0021] Etching the array pattern multiple times for a short time through a plasma processing method to form the hollow pattern and form the pattern layer on the substrate.

[0022] The embodiment of the present application provides a photolithography medium for forming a pattern layer on a substrate with micro-nano structures. The photolithography medium is made of a thermosensitive photoresist. Through the application of the thermosensitive photoresist, high-resolution patterning of micro-nano structures can be achieved at the nanometer level, thus being suitable for the manufacture of ultra-high density integrated circuits and nano-scale functional devices. Description of the Drawings

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0024] Figure 1 Schematic diagram of the line pattern and height curve written by a thermal probe for the photolithography medium provided by the embodiment of the present application;

[0025] Figure 2Schematic diagram of the relative relationship between the pattern scribed by a thermal probe on the lithography medium provided by the embodiments of the present application and the set temperature;

[0026] Figure 3 Schematic diagrams of the AFM scanning pattern, three-dimensional pattern and height scanning curve of the lithography medium provided by the embodiments of the present application scribed by a thermal probe in a sine curve;

[0027] Figure 4 Schematic flow chart of the preparation method of the micro-nano structure provided by the embodiments of the present application.

[0028] The realization, functional characteristics and advantages of the purpose of the present application will be further described with reference to the embodiments and the accompanying drawings. Detailed implementation manners

[0029] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0030] It should be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0031] It should also be understood that the terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0032] The embodiments of the present application provide a lithography medium for preparing a micro-nano structure. The micro-nano structure includes a substrate and a pattern layer on the substrate. The pattern layer is formed by the lithography medium, and the lithography medium is made of a thermosensitive photoresist.

[0033] Specifically, as a thermosensitive material, the thermosensitive photoresist can achieve precise patterning at the nanoscale through the thermal effect of the scanning thermal probe lithography technology, breaking through the diffraction limit of traditional lithography. The minimum feature size can be as low as less than 50 nm, so it is suitable for the manufacture of ultra-high density integrated circuits and nano-scale functional devices.

[0034] Meanwhile, scanning thermal probe lithography is adopted, which eliminates wet processing steps such as development and etching. Pattern formation is directly completed through a thermal probe, and then electrodes are formed through plasma treatment and evaporation, achieving all-dry manufacturing, significantly reducing processing steps and the risk of contamination. Moreover, the thermosensitive photoresist can be applied on various substrates and exhibits excellent stability and compatibility during subsequent processing, making it suitable for the fabrication of more types of nano-devices.

[0035] In addition, the thermal probe lithography technology is insensitive to external humidity and temperature. It directly processes patterns using thermal effects, avoiding the uncertainties caused by environmental fluctuations in wet processes and improving the consistency and reproducibility of patterns.

[0036] Therefore, the embodiments of this application provide a lithography medium for forming a pattern layer on the substrate of a micro-nano structure. This lithography medium is made of a thermosensitive photoresist. Through the application of the thermosensitive photoresist, high-resolution patterning of micro-nano structures can be achieved at the nano level, thus being suitable for the fabrication of ultra-high density integrated circuits and nano-scale functional devices.

[0037] Furthermore, the thermosensitive photoresist is PPC (Polypropylene carbonate), and the lithography medium is formed from a PPC solution with a concentration of 6.5%.

[0038] Specifically, the PPC material has the property of thermal decomposition at high temperatures. In thermogravimetric analysis, when the temperature exceeds 300 °C, its mass loss is close to 100%. For example, the prepared PPC solution is dropped onto the surface of a substrate such as a SiO2 / Si (SiO2 thickness 285 nm) silicon wafer through a pipette gun, covering the entire sample surface with the solution. Then, spin coating is performed using a spin coater (low speed 1000 rpm for 10 s + high speed 9900 rpm for 60 s). After spin coating, a thin PPC film is obtained. Since the viscosity between PPC molecules is strong and the rotation speed is fast during the spin coating process, the spin coating thickness fluctuates within a certain range during high-speed spin coating. In scanning thermal probe technology, the heated tip part can reach the thermal decomposition temperature of PPC, and a pyrolysis reaction will occur at the position of the PPC layer in contact with the heated probe. When the tip temperature is higher than the thermal decomposition temperature, the PPC around the tip will directly sublime to form a pattern.

[0039] Refer to Figure 1 , Figure 1 which is a schematic diagram of the line pattern and height curve written by a thermal probe for the lithography medium provided by the embodiments of this application. As a thermosensitive photoresist, PPC can achieve a relatively small writing accuracy. As can be seen from Figure 1 , as a thermosensitive photoresist, PPC can achieve a relatively good writing effect within the sub-micron accuracy range. At its minimum writing accuracy, a width of approximately 20 nm can be achieved. Figure 1also shows the height curve of the written pattern. From Figure 1 as can be seen, there is accumulation at the edge of the written line pattern. When reaching extremely small nanosizes, since the contact time between the probe and the sample surface during probe writing is only dozens of microseconds, the heat on the probe cannot fully act on the sample layer, resulting in the accumulation of part of the thermosensitive adhesive layer.

[0040] Referring to Figure 2 , Figure 2 is a schematic diagram of the relative relationship between the pattern written by the thermal probe on the lithography medium provided in the embodiment of the present application and the set temperature. The scanning thermal probe acts through the heat of the tip and the adhesive layer. As the set temperature changes, the writing effect on the sample surface will also be different. As Figure 2 shown, Figure 2 the temperature shown in is the temperature set in the instrument software, and the actual temperature of the tip is about one-third of the temperature set in the software. The complete thermal decomposition temperature of the PPC material is slightly greater than 300 °C. Therefore, as can be seen from Figure 2 , when the set temperature reaches about 900 °C, a relatively good writing effect can be achieved on the PPC.

[0041] Referring to Figure 3 , Figure 3 is a schematic diagram of the AFM scanning pattern, three-dimensional pattern and height scanning curve of the sinusoidal curve writing of the lithography medium provided in the embodiment of the present application by the thermal probe. Using the scanning thermal probe technology to write on the PPC has an advantage that traditional lithography technology does not have, that is, it can perform custom writing in the third dimension, that is, the vertical depth direction. As Figure 3 shown, the PPC can be written with a sinusoidal curve in the vertical direction through a grayscale pattern. Figure 3 The left figure a in is the AFM scanning pattern of the sample surface after writing, the middle figure b is the corresponding three-dimensional pattern, and the right figure c is the height scanning curve at the dotted line position in the left figure a. By writing at different depths in the vertical direction, it can be used for subsequent grayscale amplification in micro-nano processing.

[0042] In summary, in the embodiment of the present application, by using PPC as the thermosensitive photoresist and combining the scanning thermal probe technology, ultra-high resolution patterning below sub-100 nm or even 50 nm is achieved, breaking through the limitations of traditional lithography. This technical solution can also achieve precise patterning on a variety of substrates, and the PPC material has high thermal stability and can adapt to high-temperature treatment, solving the problem of limited selection of traditional photoresist materials. In addition, the precise thermal effect processing of the scanning thermal probe avoids the sensitivity of traditional lithography to humidity and temperature, improving the pattern accuracy and stability. Overall, the embodiment of the present application provides a more efficient, flexible and environmentally friendly solution for micro-nano manufacturing.

[0043] In addition, it should be noted that PMMA (polymethyl methacrylate), as a thermosensitive photoresist replacing PPC, is a common photoresist material and is widely used in electron beam lithography and other micro-nano processing technologies. By adjusting the photosensitivity and thermal response characteristics of PMMA, it can be used as an alternative resist material for thermal probe lithography. PMMA has low thermoplasticity and can be quickly softened under heating conditions, thus meeting the requirements of scanning thermal probe technology.

[0044] Furthermore, the PPC solution is formed by dissolving PPC solid particles into anisole solvent.

[0045] Specifically, 1.5 g of poly(propylene carbonate) PPC solid particles are dissolved into 21.5 g of anisole solvent, and the solution concentration is 1.5 / 23 = 6.522%, and it is stirred for 24 h under heating at 50 °C by a magnetic stirrer to obtain the target PPC solution.

[0046] Furthermore, the thickness of the PPC film is between 250 nm and 300 nm.

[0047] For example, the prepared PPC solution is dropped onto the surface of a substrate such as a SiO2 / Si (SiO2 thickness 285 nm) silicon wafer by a pipette gun so that the solution covers the entire sample surface, and then spin coating is carried out by a spin coater (low speed 1000 rpm for 10 s + high speed 9900 rpm for 60 s). After spin coating, a thin PPC film with a thickness of about 250 nm - 300 nm is obtained. Because the viscosity between PPC molecules is strong and the rotation speed is fast during the spin coating process, its spin coating thickness fluctuates within a certain range during the high-speed spin coating process.

[0048] Furthermore, the thermal decomposition temperature of the PPC film is greater than 300 °C.

[0049] As shown above, the PPC material has the property of thermal decomposition at high temperatures. In thermogravimetric analysis, when the temperature exceeds 300 °C, its mass loss is close to 100%. Therefore, in the scanning thermal probe technology (t-SPL), the heated tip part can reach the thermal decomposition temperature of PPC, and a thermal decomposition reaction will occur at the position of the PPC layer contacted by the heating probe. When the tip temperature is higher than the thermal decomposition temperature, the PPC around the tip will directly sublime to form a pattern.

[0050] Second aspect, referring to Figure 4 , the embodiments of the present application provide a method for preparing a micro-nano structure, including the following steps:

[0051] S101: Spin coat a thermosensitive photoresist on a substrate; and

[0052] S102: Etch a hollow pattern on the thermosensitive photoresist to form a pattern layer on the substrate.

[0053] In the method for preparing a micro-nano structure provided by an embodiment of the present application, first, a photoresist film needs to be spin-coated on a substrate, and then a hollow pattern is etched on the photoresist film to form a pattern layer on the substrate. The photoresist medium is made of a thermosensitive photoresist. Through the application of the thermosensitive photoresist, high-resolution patterning of micro-nano structures can be achieved at the nanometer level, thus being suitable for the manufacture of ultra-high density integrated circuits and nano-scale functional devices.

[0054] It should be noted that after etching a hollow pattern on the thermosensitive photoresist to form a pattern layer on the substrate, the following steps are further included:

[0055] S103: Evaporating a metal medium on the exposed portions of the pattern layer and the substrate; and

[0056] S104: Covering the metal medium on the pattern layer with an adhesive, and removing the pattern layer and the metal medium above the pattern layer by mechanically peeling the adhesive to prepare a micro-nano structure including the substrate and a metal layer.

[0057] In the method for preparing a micro-nano structure provided by an embodiment of the present application, first, a photoresist film needs to be spin-coated on a substrate, and then a hollow pattern is etched on the photoresist film to form a pattern layer, and a metal medium is evaporated on the exposed portions of the pattern layer and the substrate. Finally, the metal medium on the pattern layer is covered with an adhesive, and the pattern layer and the metal medium above the pattern layer are removed by mechanically peeling the adhesive to prepare a micro-nano structure including the substrate and a metal layer. Therefore, the method for preparing a micro-nano structure provided by an embodiment of the present application can improve the resolution and processing efficiency of the micro-nano structure, and can reduce costs and avoid environmental pollution problems through high-precision pattern etching, dry stripping process, and efficient processing capabilities.

[0058] Furthermore, the thermosensitive photoresist is PPC. Spin-coating the thermosensitive photoresist on the substrate includes:

[0059] Dropping the prepared PPC solution on the surface of the substrate; and

[0060] Forming the PPC film on the substrate through spin coating operation.

[0061] Specifically, the PPC (Poly propylene carbonate) material has the property of thermal decomposition at high temperatures. In thermogravimetric analysis, when the temperature exceeds 300 °C, its mass loss is close to 100%. For example, the prepared PPC solution is dropped onto the surface of a substrate such as a SiO2 / Si (SiO2 thickness 285 nm) silicon wafer using a pipette, so that the solution covers the entire sample surface, and then spin coating is performed using a spin coater (low speed 1000 rpm for 10 s + high speed 9900 rpm for 60 s). After spin coating, a thin PPC film with a thickness of about 250 nm - 300 nm is obtained. Because the viscosity between PPC molecules is strong and the rotation speed during the spin coating process is fast, the spin coating thickness fluctuates within a certain range during the high-speed spin coating process.

[0062] Furthermore, the concentration of the PPC solution is 6.5%. That is, 1.5 g of polypropylene carbonate PPC solid particles need to be dissolved in 21.5 g of anisole solvent, and the solution concentration is 1.5 / 23 = 6.522%. Then, it is stirred for 24 h under heating at 50 °C using a magnetic stirrer to obtain the target PPC solution for subsequent spin coating operations.

[0063] Furthermore, etching a hollow pattern on the photoresist film to form a pattern layer on the substrate includes:

[0064] Etching an array pattern on the photoresist film using a thermal probe; and

[0065] Etching the hollow pattern on the array pattern using a plasma processing method to form the pattern layer on the substrate.

[0066] Specifically, in the scanning thermal probe technique (t-SPL), the heated tip part can reach the pyrolysis temperature of PPC, and the pyrolysis reaction will occur at the position of the PPC layer contacted by the heating probe. When the tip temperature is higher than the pyrolysis temperature, the PPC around the tip will directly sublime to form a pattern. The part of PPC where the temperature around the probe is not sufficient to reach sublimation will still melt and will be pushed by the force applied to the probe during the process of probe movement and writing, resulting in partial accumulation of PPC at the pattern edge position. The scanning thermal probe technique supports pattern import and can achieve the writing of any pattern.

[0067] The pattern depth engraved by the thermal probe on the surface of the PPC sample can be 180 nm, and this depth can be set. After engraving the pattern array, the PPC sample is subjected to O2 / Ar plasma treatment, and the PPC on the surface is reacted during the plasma treatment, resulting in a reduction in the thickness of the PPC layer.

[0068] The preparation method of the micro-nano structure provided by the embodiments of the present application can achieve pattern etching with micron-level accuracy by precisely controlling the heating temperature and scanning path of the thermal probe. At the same time, it can achieve high-precision etching of metal patterns at the nano level (below 100 nm), overcoming the resolution limitations of traditional lithography technology, meeting the requirements of microelectronics and nano-device manufacturing for high-precision patterns, and being able to efficiently process different materials (such as polymers, metals, semiconductors, etc.) with strong material adaptability. By means of local heating, it avoids thermal damage in traditional high-temperature etching and is particularly suitable for the processing of flexible substrates and temperature-sensitive materials. In addition, compared with the traditional multiple exposure and development processes, the t-SPL technology realizes pattern etching through a single scan, which can improve production efficiency. Its flexible processing method enables rapid adjustment and optimization of processing conditions to meet the requirements of different sizes and complex patterns.

[0069] It should be noted that in the embodiments of the present application, a laser beam or an electron beam can be used to replace the heating method of the scanning thermal probe. For example, a focused laser beam is used to locally heat the sample surface, and due to the high-precision focusing characteristics of the laser, pattern etching can also be achieved at the nano scale. Other nano-manufacturing technologies such as nanoimprint lithography or focused ion beam etching can also be considered as alternative methods. The nanoimprint lithography transfers patterns by applying an imprinting force on the material surface, while the focused ion beam directly etches the material by accelerating the ion beam.

[0070] In addition, the embodiments of the present application can also use other non-thermal methods such as lithography technology, electron beam exposure, ultrasonic etching, etc. to perform pattern transfer at the micro-nano scale. Although the above methods have different principles, they can also achieve the effect of high-precision pattern transfer.

[0071] Further, the method of etching the hollow pattern on the array pattern by a plasma processing method to form a pattern layer on the substrate includes:

[0072] The hollow pattern is formed by etching the array pattern multiple times for a short time by a plasma processing method to form the pattern layer on the substrate.

[0073] Specifically, the PPC sample is processed under the conditions of 5W O2 plasma or 5W Ar plasma. The gas flow rate is 250 ml / min, and the processing time is 3 min + 3 min + 3 min. Multiple short-time processes are carried out to prevent the etching rate from being too fast due to excessive temperature during the plasma process.

[0074] Further, in some embodiments of the present application, the metal layer includes a first metal layer and a second metal layer, and the second metal layer is located above the first metal layer.

[0075] Specifically, when it is ensured that the PPC patterning position has been etched into the SiO2 / Si substrate during the plasma treatment process, the next step of metal evaporation is carried out. In the embodiment of the present application, a metal medium is evaporated on the sample surface by EBE (Electron Beam Evaporation), and finally a micro-nano structure including the substrate and the metal layer is formed. The metal layer includes a first metal layer and a second metal layer, and the second metal layer is located above the first metal layer.

[0076] Further, in some embodiments of the present application, the material of the first metal layer is metal Cr (chromium), and the material of the first metal layer is metal Au (gold).

[0077] Specifically, for example, Cr and Au can be evaporated on the sample surface as metal patterns. Au can be used as a device electrode, and Cr can significantly enhance the adhesion between Au and the substrate.

[0078] Further, in some embodiments of the present application, the thickness of the first metal layer is 3 to 7 nm, and the thickness of the second metal layer is 15 to 20 nm.

[0079] For example, 5 nm Cr and 20 nm Au can be evaporated on the sample surface as metal patterns. Of course, the specific thickness of the metal layer depends on the actual situation and is not limited herein.

[0080] After the metal medium evaporation is completed, the sample can be placed on a glass slide, and then one or two layers of 3M tape are covered on the sample surface, and the surface is gently pressed with tweezers to make the tape and the sample surface fully contact. Then the tape is slowly peeled off from a corner of the sample. At this time, the metal layer at the patterned position remains on the substrate, while the PPC and the metal layer at other positions will be lifted under the action of the tape, leaving only the metal pattern.

[0081] It should be noted that the embodiment of the present application realizes the full-dry preparation of metal patterns on the SiO2 / Si substrate. By combining thermal probe writing and plasma treatment, the preparation of micro-nano metal structures is realized by full-dry method. Any micro-nano pattern can be realized by the thermal probe technology and the subsequent dry stripping technology, which is not limited herein.

[0082] In addition, the embodiment of the present application also provides a micro-nano structure, which is made by the method described in any one of the above. The specific preparation method of this micro-nano structure refers to the above embodiments. Since the specific preparation method of the micro-nano structure adopts all the technical solutions of all the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be elaborated herein one by one.

[0083] As described above, it is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A photolithographic medium for preparing micro-nano structures, characterized in that: The micro-nano structure comprises a substrate and a pattern layer on the substrate, wherein the pattern layer is formed by the photolithography medium, and the photolithography medium is made of thermosensitive photoresist.

2. The photolithographic medium according to claim 1, wherein: The thermal-sensitive photoresist is PPC, and the photolithographic medium is formed by a PPC solution with a concentration of 6.5%.

3. The photolithographic medium according to claim 2, wherein: The PPC solution is formed by dissolving PPC solid particles in anisole solvent.

4. The photolithographic medium according to claim 3, characterized in that The thickness of the PPC film is between 250nm and 300nm.

5. The photolithographic medium according to claim 4, characterized in that The thermal decomposition temperature of the PPC film is greater than 300°C.

6. A method for preparing a micro-nano structure, comprising the following steps: spin coating a thermal sensitive photoresist on the substrate; and A hollow pattern is etched on the thermal photoresist to form a pattern layer on the substrate.

7. The method according to claim 6, characterized in that The thermal photoresist is PPC, and the process of spin coating the thermal photoresist on the substrate comprises: Dropping the prepared PPC solution on the surface of the substrate; and The PPC film is formed on the substrate by a spin coating operation.

8. The method according to claim 7, characterized in that The concentration of the PPC solution was 6.5%.

9. The method according to any one of claims 6 to 8, characterized in that: The step of etching a hollow pattern on the photoresist film to form a pattern layer on the substrate comprises: Etching an array pattern on the photoresist film by a thermal probe; and The hollow pattern is etched on the array pattern by a plasma treatment method to form the pattern layer on the substrate.

10. The method according to claim 9, characterized in that The method of etching the hollow pattern on the array pattern by a plasma treatment method to form a pattern layer on the substrate includes: The array pattern is etched multiple times in a short time by a plasma treatment method to form the hollow pattern, and the pattern layer is formed on the substrate.

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