Stepped-change conductive high-transmittance micro-nano grid photoelectric glass window and processing method thereof

Abstract

The invention relates to a step-changing conductive high-transmittance micro-nano grid photoelectric glass window and a processing method thereof, and the processing method comprises the following steps: design of a photoelectric glass window structure: the transmittance of the photoelectric glass window is greater than or equal to 85%, the sheet resistance is less than 100 omega / square, and a network structure is designed based on the design; a mask plate is prepared, wherein the designed grid structure is prepared into the mask plate; surface treatment: plating an antireflection film layer on the photoelectric glass window; manufacturing the structure: spin-coating anti-reflection glue and photoresist on the antireflection film layer to obtain photoelectric glass with a glue layer; placing the photoelectric glass with the adhesive layer under a mask plate for exposure to obtain a designed grid structure; transferring the structure: performing partition etching on the grid structure to obtain a photoelectric glass grid window with stepped groove depth; and finally, carrying out zoning coating. According to the step-changing conductive high-transmittance micro-nano grid photoelectric glass window, the problem of photoelectric conversion loss when the photoelectric glass window is coupled with a photoelectric cathode can be solved, and the electron loss can be reduced to be lower than 5%.

Description

Technical Field

[0001] This invention belongs to the field of optical imaging, specifically relating to a stepped-variable conductive high-transmittance micro / nano grid optoelectronic glass window and its fabrication method. Background Technology

[0002] As the core component for converting photons into electrons, the photocathode's high-performance characteristics make it irreplaceable in emerging fields such as low-light night vision, space science and astronomical exploration, high-energy physics and nuclear detection, medical imaging and life sciences, and consumer electronics. The performance of the photocathode's glass window directly determines the sensitivity, spectral response range, and signal-to-noise ratio of the image intensifier. Currently, when anti-halo glass windows are coupled to the photocathode, the insulating properties of the anti-halo glass window can easily lead to insufficient electron conversion efficiency, resulting in an insufficient number of electrons entering the microchannel plate, thus affecting the overall performance of the image intensifier. Summary of the Invention

[0003] The main objective of this invention is to provide a method for fabricating a conductive, high-transmittance micro / nano grid optoelectronic glass window that reduces the stepwise variation in electron loss during coupling between the optoelectronic glass window and the photocathode.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for fabricating a stepped-variable conductive high-transmittance micro / nano grid optoelectronic glass window includes the following steps: 1) Photoelectric glass window structure design: The photoelectric glass window has a transmittance ≥85% and a sheet resistance <100Ω / □. Based on this, the groove depth, line width, and period of the grid are designed. T (光电玻璃窗口) %= T (光电玻璃材料) %-(linewidth / period)% ... Where T (光电玻璃窗口) % indicates the transmittance of the photoelectric glass window; T (光电玻璃材料) This indicates the transmittance of the photoelectric glass material; linewidth / period indicates the ratio of linewidth to period. 2) Mask fabrication: The mesh structure designed in step 1) is fabricated into a mask; 3) Surface treatment of photoelectric glass window: A certain thickness of antireflective coating is deposited on the photoelectric glass window, and the surface roughness of the antireflective coating is made less than 1nm by chemical mechanical polishing; 4) Fabrication of the structure on the optoelectronic glass window: The anti-reflective adhesive is uniformly spin-coated onto the antireflective film layer obtained in step 3), baked for the first time, then uniformly spin-coated with photoresist, and baked for the second time to obtain optoelectronic glass with adhesive layer; the optoelectronic glass with adhesive layer is placed under a photomask and exposed using a photolithography machine, and the mesh structure is transferred to the optoelectronic glass window through exposure, and the mesh structure designed in step 1) is obtained after development; 5) Transfer of photoelectric glass window structure: The grid structure obtained in step 4) is divided into sections and then etched to obtain a photoelectric glass grid window with stepped groove depth. The groove depth increases or decreases from the center area to the edge area of ​​the photoelectric glass window. 6) Partitioned coating of optoelectronic glass window structure: The area with the deep groove of the stepped groove on the optoelectronic glass grid window is coated with a metal film layer of a certain thickness by magnetron sputtering. Then, the anti-reverse adhesive and photoresist are removed by a resist remover to obtain an optoelectronic glass grid window with a metal layer only in the grid groove; that is, a conductive high-transmittance micro-nano grid optoelectronic glass window.

[0005] The network structure is an interconnected pattern, the linewidth is 300-3000nm, and the period is 3.3um-33um; the photoelectric glass material has a transmittance of ≥94%. The thickness of the metal film is greater than the depth of the etched trench; The mask is prepared by electron beam direct writing, and the substrate for preparing the mask is quartz glass with a low coefficient of thermal expansion.

[0006] In step 3), the photoelectric glass window is ultrasonically cleaned in isopropanol for 5-15 minutes before the antireflection coating is deposited. The cleaned photoelectric glass window is then placed in an atomic layer deposition or chemical vapor deposition device to deposit the antireflection coating on the photoelectric glass window. The ultrasonic cleaning power is 200-300W, and the frequency is 40-80 kHz; The antireflective coating is made of at least one of silicon dioxide, aluminum oxide, titanium dioxide, and hafnium oxide. The thickness of the antireflective coating is 100-300 nm greater than the groove depth of the grid; The thickness of the metal film is greater than the depth of the etched trench by 50-200 nm; The photoelectric glass window is an irregularly shaped object, including a first step body and a second step body disposed on the first step body. The first step body and the second step body are circular or polygonal in shape. The diameter or side length of the first step body is 20-100mm, the diameter or side length of the second step body is 10-50mm, and the thickness of the photoelectric glass window is 2-20mm.

[0007] The spin coater speed for the anti-reflective adhesive and photoresist is 2000-5000 rpm. The thickness of the anti-reflective adhesive layer is 100-300 nm, and the thickness of the photoresist layer is 300 nm-1000 nm. The temperature of the first baking is 100-130℃, and the baking time is 60-120 s. The temperature of the second baking is 110-160℃, and the baking time is 80-120 s. The intensity of the exposed light is 1.2-3 mW / cm². 2 The exposure time is 20-80s, the baking temperature after exposure is 110-160℃, the baking time is 80-120s, and the developing time is 35-90s.

[0008] In step 5), the etching gas is selected from two or more of oxygen, carbon tetrafluoride, argon, trifluoromethane, sulfur hexafluoride and nitrogen. The flow rate of the etching gas is 2-80 L / min, the power is 40-320 W, and the etching depth is 50 nm-1000 nm.

[0009] The target material for the magnetron sputtering metal film is gold, silver, aluminum, tungsten, or chromium. The temperature during the metal film deposition is 25-160℃, the deposition time is 30-1000s, and the power is 60-500W.

[0010] The adhesive stripper has a power of 300-800W and a stripping time of 10-20 minutes. It is used to remove the anti-reverse adhesive and photoresist on the photoelectric glass mesh window. Then, the photoelectric glass mesh window is placed in a high-purity isopropanol solution for ultrasonic cleaning for 5-10 minutes. The ultrasonic power is 150-500W and the ultrasonic frequency is 40-80kHz. It is then dried in a vacuum oven at a temperature of 80-100℃ for 10-20 minutes.

[0011] After the grid structure obtained in step 4) is divided into partitions, it includes a central region, a middle region and an edge region. The middle region is located between the central region and the outer region. The central region is a high-transparency region or a low-transparency region. The edge region is a fully transparent region. The middle region is a low-transparency region or a high-transparency region. The partitioned etching process involves first protecting the fully transparent area with tape, then etching the high-transparency and low-transparency areas. After etching to a certain depth, the low-transparency or high-transparency areas are then protected with tape. The area not protected with tape is then etched to the required groove depth to obtain a photoelectric glass grid window with stepped groove depth.

[0012] Furthermore, before protecting the fully transparent area with tape, the high-transparency area, low-transparency area, and fully transparent area are simultaneously etched.

[0013] The present invention also provides a stepped conductive high-transmittance micro / nano grid optoelectronic glass window, which is prepared according to the processing method described above.

[0014] By employing the above technical solution, the present invention has at least the following advantages: 1. This invention provides a certain level of conductivity without affecting transmittance, thereby reducing electron loss when the conductive, high-transmittance micro / nano grid photoelectric glass window is coupled with a photocathode. Traditional photoelectric glass windows experience electron loss exceeding 20% ​​when coupled with a photocathode. This invention improves the photoelectric conversion loss problem during coupling, reducing electron loss to below 5%.

[0015] 2. The photoelectric glass window of the present invention has high transmittance, and the area occupied by the micro-nano structure can be flexibly adjusted according to actual needs, thereby achieving both high transmittance and conductivity.

[0016] 3. The photoelectric glass window of the present invention has controllable conductivity. The micro-nano structure is prepared by step etching method, and the groove depth and linewidth can be adjusted according to the application requirements.

[0017] 4. The photoelectric glass window of the present invention has high uniformity of grid structure. By coating the anti-halo photoelectric glass window with an anti-reflective film, the consistency of the grid structure in line width and groove depth in the same area is ensured.

[0018] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the stepped-change conductive high-transmittance micro / nano grid optical glass provided in an embodiment of the present invention; Figure 2 This is the transmittance curve of the stepped-varying conductive high-transmittance micro / nano grid optical glass of Embodiment 1 provided by the present invention; Figure 3 This is the transmittance curve of the stepped-varying conductive high-transmittance micro / nano grid optical glass of Embodiment 2 provided by the present invention; Figure 4 This is the transmittance curve of the stepped-varying conductive high-transmittance micro / nano grid optical glass of Embodiment 3 provided by the present invention. Detailed Implementation

[0020] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the specific implementation methods, structures, features, and effects of the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0021] like Figure 1As shown, this invention provides a stepped conductive high-transmittance micro / nano grid optoelectronic glass window, which is irregularly shaped and includes a first stepped body 1 and a second stepped body 2 disposed on the first stepped body 1. Both the sides of the first stepped body 1 and the second stepped body 2 are blackened to concentrate light and prevent halos. The diameter of the second stepped body 2 is smaller than that of the second stepped body 1. An antireflective film 3 is deposited on the upper surface of the second stepped body to enhance transparency and facilitate etching. The antireflective film 3 has a conductive high-transmittance window, which serves two purposes: first, by controlling parameters such as the period and linewidth of the micro / nano structure, the required sheet resistance and transmittance can be achieved; second, it improves the electron conversion efficiency when the optoelectronic glass window couples with the photocathode. The conductive high-transmittance window includes a low-transmittance region 4 at the center, a high-transmittance region 5 surrounding the low-transmittance region 4, and other regions surrounding the high-transmittance region 5 that are fully transparent regions 6. The low-transmittance region 4 and the high-transmittance region 5 can be interchanged as needed. The low-transmittance region 4, the high-transmittance region 5, and the fully transparent region 6 constitute the upper surface of the second stepped body.

[0022] The present invention provides a stepped conductive high-transmittance micro-nano grid optoelectronic glass that enables the optoelectronic glass window to have a stepped conductive function under the premise of high transmittance, thereby improving the problem of insufficient electron conversion efficiency when the anti-halo optoelectronic glass window is coupled with the photocathode.

[0023] This invention provides a method for fabricating a stepped-variable conductive high-transmittance micro / nano grid optoelectronic glass window, comprising the following steps: 1) Photoelectric glass window structure design: The photoelectric glass window has a transmittance ≥85% and a sheet resistance <100Ω / □. Based on this, the groove depth, line width, and period of the grid are designed. T (光电玻璃窗口) %= T (光电玻璃材料) %-(linewidth / period)% ... Among them, T (光电玻璃窗口) % indicates the transmittance of the photoelectric glass window; T (光电玻璃材料) This indicates the transmittance of the photoelectric glass material; linewidth / period indicates the ratio of linewidth to period. 2) Mask fabrication: The mesh structure designed in step 1) is fabricated into a mask; 3) Surface treatment of optoelectronic glass window: A certain thickness of antireflective coating is deposited on the optoelectronic glass window, and the surface roughness of the antireflective coating is reduced to less than 1 nm by chemical mechanical polishing to facilitate the preparation of micro and nano structures. Before depositing the antireflective coating, the areas of the optoelectronic glass window that do not need to be coated with the antireflective coating are protected with high temperature tape. 4) Fabrication of the structure on the optoelectronic glass window: Anti-reflective adhesive is uniformly spin-coated onto the antireflective film layer obtained in step 3), followed by a first baking, then uniformly spin-coated with photoresist, and a second baking, resulting in optoelectronic glass with an adhesive layer. The photoresist-coated optoelectronic glass is placed under a photomask for exposure using a photolithography machine. The exposure transfers the mesh structure onto the optoelectronic glass window. After development, the mesh structure designed in step 1) is obtained. The area of ​​the mesh structure can be adjusted according to specific needs, and it can cover the entire optoelectronic glass window. The groove depth increases or decreases from the center area to the edge. The mesh structure can also exist in localized areas of the optoelectronic glass window.

[0024] 5) Transfer of photoelectric glass window structure: The grid structure obtained in step 4) is divided into sections and then etched to obtain a photoelectric glass grid window with stepped groove depth. The groove depth increases or decreases from the center area to the edge area of ​​the photoelectric glass window. Specifically, high-transparency areas, low-transparency areas, and fully transparent areas are etched, and then the fully transparent areas are protected with tape. The high-transparency and low-transparency areas are etched, and after etching to a certain depth, the high-transparency areas are protected with tape. The low-transparency areas that are not protected with tape are then etched to the required groove depth to obtain a photoelectric glass grid window with stepped groove depth.

[0025] Alternatively, the fully transparent area can be protected with tape without etching, and then the high-transparency and low-transparency areas can be etched. After etching to a certain depth, the high-transparency area can be protected with tape again, and the low-transparency area that is not protected with tape can be etched to the required groove depth to obtain a photoelectric glass grid window with stepped groove depth.

[0026] 6) Partitioned Coating of Optoelectronic Glass Window Structure: Metal films of varying thicknesses are deposited on the etched groove areas of the stepped-groove optoelectronic glass grid window using magnetron sputtering. Then, the anti-reverse adhesive and photoresist are removed using a photoresist remover. When the fully transparent area is protected with tape, the low-transparency and high-transparency areas of the stepped groove deep optoelectronic glass grid window are coated with a metal film layer of a certain thickness using magnetron sputtering. When the fully transparent area is also etched with groove depth, the low-transparency, high-transparency, and fully transparent areas are coated with a metal film layer of a certain thickness using magnetron sputtering. Then, the anti-reverse adhesive and photoresist are removed using a resist remover to obtain an optoelectronic glass grid window with a metal layer only in the grid groove; that is, a conductive high-transparency micro-nano grid optoelectronic glass window.

[0027] 7) Transmittance and Sheet Resistance Testing of Photoelectric Glass Window Structure: A sheet resistance meter and spectrophotometer were used to test the sheet resistance and transmittance of different areas of the photoelectric glass window. Calibration was performed using standard plates before testing. During testing, the test area was ensured to be dry and clean, and the probes were kept at equal intervals and with constant pressure to avoid affecting the test results.

[0028] 8) Coupling of photoelectric glass window and photocathode: The conductive high-transmittance micro-nano grid photoelectric glass window is coupled to the photocathode under vacuum and assembled with other components to test the overall performance such as sensitivity and resolution.

[0029] Furthermore, the network structure is a square grid, a diamond grid, or any other interconnected grid pattern, the linewidth is 300-3000nm, the period is 3.3um-33um, and the transmittance of the optoelectronic glass material is ≥94%.

[0030] Since the transmittance of the optoelectronic glass window should be ≥85% and the sheet resistance <100Ω / □, the shape, groove depth, linewidth, and period of the micro / nano structure need to be designed accordingly. The transmittance of the optoelectronic glass window is affected by the optoelectronic glass material and the micro / nano structure, that is, theoretically T (光电玻璃窗口) %= T (光电玻璃材料) % - (linewidth / period)%, to ensure the conductivity of the optoelectronic glass window, a cross-linked network structure should be provided. The network structure can be a square mesh, a diamond mesh, or other amorphous structures, with the meshes intersecting each other. The transmittance of the optoelectronic glass material is ≥94%. To ensure the transmittance of the optoelectronic glass window is ≥85%, the linewidth / period should be ≤9%. Therefore, the linewidth should be 300-3000nm, and the period should be 3.3um-33um.

[0031] Preferably, the substrate for preparing the mask is quartz glass with a low coefficient of thermal expansion.

[0032] The photomask was fabricated using quartz glass with good light transmittance and stability and a low coefficient of thermal expansion as the substrate. The photomask was prepared using electron beam direct writing, with polymethyl methacrylate (PMMA) as the electron beam photoresist. Spin coating was employed to ensure thickness uniformity within 1.5%, guaranteeing consistent sensitivity to exposure dose and development time. The exposure dose was 100-300 μC / cm². 2 During this process, the development method is immersion.

[0033] Further, in step 3), the photoelectric glass window is cleaned in isopropanol before the antireflection coating is deposited, and the cleaned photoelectric glass window is placed in an atomic layer deposition (ALD) or chemical vapor deposition (CVD) apparatus to deposit the antireflection coating on the photoelectric glass window. The antireflective coating is made of at least one of silicon dioxide, aluminum oxide, titanium dioxide, and hafnium oxide. The thickness of the antireflective coating is 100-300 nm greater than the groove depth of the grid, ensuring that the antireflective coating can completely fill the grooves of the grid. The thickness of the metal film is 50-200 nm greater than the depth of the etched trench. This ensures that the trench is completely filled with the metal film and facilitates subsequent cleaning.

[0034] The photoelectric glass window is an irregularly shaped object, including a first step body and a second step body disposed on the first step body. The first step body and the second step body are square, circular or polygonal in shape. The diameter or side length of the first step body is 20-100mm, the diameter or side length of the second step body is 10-50mm, and the thickness of the photoelectric glass window is 2-20mm.

[0035] Furthermore, the spin coater speed for the anti-reflective adhesive and photoresist is 2000-5000 rpm, the thickness of the anti-reflective adhesive layer is 100-300 nm, the thickness of the photoresist layer is 300 nm-1000 nm, the temperature of the first baking is 100-130℃, the time of the first baking is 60-120 s, the temperature of the second baking is 110-160℃, and the time of the second baking is 80-120 s; The intensity of the exposed light is 1.2-3 mW / cm². 2 The exposure time is 20-80s, the baking temperature after exposure is 110-160℃, the baking time is 80-120s, and the developing time is 35-90s.

[0036] Furthermore, in step 5), the etching gas is one or more of oxygen, carbon tetrafluoride, argon, trifluoromethane, sulfur hexafluoride, and nitrogen. The flow rate of the etching gas is 2-80 L / min, the power is 40-320 W, the etching depth is 50 nm-1000 nm, and the groove depth increases or decreases from the center area of ​​the photoelectric glass window to the edge.

[0037] To ensure sheet resistance <100Ω / □, the structural depth should be reasonably controlled, with the preferred groove depth being 50nm-1000nm, and a material with excellent conductivity should be selected for coating.

[0038] Preferably, the target material for the magnetron sputtering metal film is gold, silver, aluminum, tungsten, or chromium, the temperature for depositing the metal film is 25-160℃, the deposition time is 30-1000s, and the power is 60-500W.

[0039] Furthermore, depending on the thickness of the adhesive, the power of the adhesive stripper is 300-800W. The adhesive stripper is used to remove the anti-reverse adhesive and photoresist on the photoelectric glass mesh window. Subsequently, it is placed in a high-purity isopropanol solution for ultrasonic cleaning for 5-10 minutes. The ultrasonic power is 300W, and the frequency is 40-80kHz. Then, it is dried in a vacuum oven at a temperature of 80-100℃ for 10-20 minutes.

[0040] The present invention will be further described below with reference to more specific embodiments.

[0041] Example 1 S1. Design a square pattern with a linewidth of 2µm and a period of 22µm. Use quartz glass with a low coefficient of thermal expansion as the photomask substrate, achieving a transmittance of 94%. Select PMMA as the electron beam photoresist and employ spin coating to ensure thickness uniformity within 1.5%. Fabricate the photomask using electron beam direct writing with an electron beam dose of 260μC / cm². 2 .

[0042] S2, Pre-treatment of the photoelectric glass window surface: The photoelectric glass window is ultrasonically cleaned in isopropanol at a power of 200W and a frequency of 80kHz for 5 minutes. The photoelectric glass window is an irregularly shaped piece. Both the first and second steps of the photoelectric glass window are circular, with the second step set on top of the first step. The diameter of the first step is 33mm, and its height is 3mm. The diameter of the second step is 20mm, and its height is 2.5mm. The sides of both the first and second steps are blackened and opaque. Before applying the antireflective coating, all areas of the photoelectric glass window that do not require antireflective coating, except for the upper surface of the second step, are protected with high-temperature tape. These areas include the sides and upper surface of the first step and the sides of the second step. Then, the photoelectric glass window is placed in a chemical vapor deposition (CVD) apparatus. A silicon dioxide film layer with a thickness of 330nm is deposited on the upper surface of the second step using silane as a precursor via CVD. The silicon dioxide film thickness was reduced by 30 nm using chemical mechanical polishing (CMP). The polishing solution was silica sol, and the rotation speed was 120 rpm. After polishing, the surface roughness of the silicon dioxide film was 0.6 nm, resulting in a photoelectric glass window coated with silicon dioxide.

[0043] S3. First, a layer of antireflective adhesive is uniformly spin-coated onto the optoelectronic glass window coated with a silicon dioxide film. The spin coater speed is 3000 rpm, and the adhesive layer thickness is 250 nm. It is then baked on a hot plate at 100°C for 60 seconds. Next, a layer of I-line photoresist is uniformly spin-coated onto the antireflective adhesive. The photoresist layer thickness is 450 nm, and the spin coater speed is 4500 rpm. Finally, it is baked on a hot plate at 120°C for 80 seconds to obtain the optoelectronic glass window with the adhesive layer.

[0044] S4. Using a photolithography machine, the photoelectric glass window with the resist layer is placed under a photomask for exposure. The light intensity is 1.8, the exposure time is 32s, and it is then baked under a hot plate at 140℃ for 90s. After returning to room temperature, it is developed in a 2.38% NMD-3 developer solution at 25℃ for 50s. NMD-3 is a commercially available developer suitable for developing thin resists (thickness less than 5μm).

[0045] S5, the diameter of the light-transmitting area of ​​the optoelectronic glass is 20mm, that is, the diameter of the second step body is 20mm. The design includes a central region with a diameter of 5mm and a groove depth of 200nm, a central region with a width of 5mm and a groove depth of 50nm, and an edge region with a width of 10mm and no structure. The product obtained in step S4 is etched in sections. First, the 10mm edge region is protected with high-temperature resistant tape. The 5mm central region and the 5mm central region are etched with plasma. The etching gases are carbon tetrafluoride, chloroform, and oxygen, with a flow rate of 10L / min, an etching time of 51s, and an etching power of 200W, etching to a groove depth of 50nm in the central region. Then, the 5mm central region is protected with high-temperature tape again. The 5mm central region is then etched separately with an etching gas flow rate of 10L / min, an etching time of 197s, and an etching power of 200W, etching to a groove depth of 200nm in the central region.

[0046] S6. Peel off the tape in the middle 5mm region of the etched optoelectronic glass window mesh structure obtained in step S5. Then, use a magnetron sputtering device to coat the middle and central regions. The coating target is tungsten, the coating time is 120s, the temperature is 25℃, the coating power is 300W, and the coating thickness is 250nm.

[0047] S7. The resist and photoresist obtained in S6 are removed using a resist stripper, leaving only the deposited tungsten in the mesh grooves. The resist stripper has a power of 500W and a stripping time of 15 minutes. Next, the sample is ultrasonically cleaned with isopropanol for 10 minutes at a power of 300W and a frequency of 40kHz. Finally, it is dried in a vacuum drying oven at 100℃ for 10 minutes.

[0048] In step S8, the transmittance and sheet resistance of the photoelectric glass metal mesh window obtained in step S7 were tested using an ultraviolet spectrometer in different regions. The tests showed that the transmittance was 86% in the 5mm central region, 89% in the 5mm middle region, and 95% in the 5mm edge region; the sheet resistance was 33Ω in the central region, 79Ω in the middle region, and non-conductive in the 10mm edge region. A schematic diagram of the fabricated photoelectric glass window with stepped high transmittance and conductivity is shown below. Figure 1 As shown, the transmittance test results are as follows: Figure 2 As shown.

[0049] Example 2 S1. Design a diamond-shaped mesh pattern with a linewidth of 300 nm and a period of 5 μm. Use quartz glass with a low coefficient of thermal expansion as the photomask substrate, achieving 95% transmittance. Select PMMA as the electron beam photoresist and employ spin coating to ensure thickness uniformity within 1%. Fabricate the photomask using direct electron beam writing with an electron beam dose of 300 μC / cm². 2 .

[0050] S2, Pre-treatment of the photoelectric glass window surface: The photoelectric glass window is ultrasonically cleaned in isopropanol at a power of 300W and a frequency of 40kHz for 10 minutes. The photoelectric glass window is an irregularly shaped piece. Both the first and second steps of the photoelectric glass window are square, with the second step set on top of the first step. The first step has a side length of 50mm and a height of 5mm, while the second step has a side length of 30mm and a height of 3mm. The sides of both the first and second steps are blackened and opaque. Before applying the antireflective coating, all areas of the photoelectric glass window that do not require antireflective coating, except for the upper surface of the second step, are protected with high-temperature tape. The photoelectric glass window is then placed in an atomic layer deposition (ALD) apparatus to deposit an aluminum oxide film layer on the upper surface of the second step of the photoelectric glass window. The thickness of the aluminum oxide film layer is 410nm. The thickness of the alumina film was reduced by 10 nm using chemical mechanical polishing (CMP). The polishing solution was silica sol, and the rotation speed was 200 rpm. After polishing, the surface roughness of the silica film was 0.8 nm, resulting in an alumina-coated optoelectronic glass window.

[0051] S3. First, a layer of antireflective adhesive is uniformly spin-coated onto the alumina-coated optoelectronic glass window. The spin coater speed is 4000 rpm, and the adhesive layer thickness is 150 nm. Then, it is baked on a hot plate at 110°C for 70 seconds. Next, a 500 nm thick layer of I-line photoresist is uniformly spin-coated onto the antireflective adhesive at 3500 rpm. Finally, it is pre-baked on a hot plate at 130°C for 100 seconds to obtain the optoelectronic glass window with the adhesive layer.

[0052] S4. The photoelectric glass window with the adhesive layer is obtained by placing it under a photomask and exposed using a photolithography machine. The light intensity is 1.4 and the exposure time is 25s. It is then baked under a hot plate at 120℃ for 80s. After returning to room temperature, it is developed in NMD-3 2.38% developer for 35s at a developer temperature of 25℃.

[0053] S5, the side length of the light-transmitting area of ​​the optoelectronic glass is 30mm. The design includes a central region with a side length of 10mm and a groove depth of 100nm, a middle region with a width of 10mm and a groove depth of 300nm, and an edge region with a width of 10mm and no structure. The product obtained in step S4 is etched in sections. First, the 10mm edge region is protected with high-temperature resistant tape. The 10mm central region and the 10mm middle region are etched using plasma. The etching gases are oxygen, carbon tetrafluoride, trifluoromethane, and nitrogen. The etching gas flow rate is 20L / min, the etching time is 45s, and the etching power is 150W. Then, the 10mm central region is protected with high-temperature tape, and the 10mm middle region is etched separately. The etching gas flow rate is 20L / min, the etching time is 110s, and the etching power is 150W.

[0054] S6. Peel off the high-temperature resistant tape in the 10mm central area of ​​the etched optoelectronic glass window mesh structure obtained in step S5. Then, use a magnetron sputtering device to coat the middle and central areas. The coating target is gold, the coating time is 180s, the temperature is 100℃, the coating power is 250W, and the coating thickness is 350nm.

[0055] S7. Using a resist remover, the anti-reflective adhesive and photoresist on the optoelectronic glass window obtained in S6 are removed, leaving only the plated gold in the grid grooves. The resist remover has a power of 600W and a removal time of 20 minutes. Next, it is ultrasonically cleaned with isopropyl alcohol for 8 minutes at a power of 150W and a frequency of 80kHz. Finally, it is dried in a vacuum drying oven at 90℃ for 15 minutes.

[0056] S8. Using an ultraviolet spectrometer, the transmittance and sheet resistance of different regions of the photoelectric glass metal mesh window obtained in S7 were tested. The test results showed that the transmittance of the 10mm central region was 90%, the transmittance of the 10mm middle region was 82%, and the transmittance of the 10mm edge region was 95%. The sheet resistance of the central region was 91Ω, the sheet resistance of the middle region was 16Ω, and the 10mm edge region was non-conductive. The transmittance test results are as follows: Figure 3 As shown.

[0057] Example 3 S1. Design a parallelogram pattern with a linewidth of 3000 nm and a period of 33 μm. Use quartz glass with a low coefficient of thermal expansion as the photomask substrate, achieving 94% transmittance. Use PMMA as the electron beam photoresist, employing spin coating to ensure thickness uniformity within 2%. Fabricate the photomask using direct electron beam writing with an electron beam dose of 320 μC / cm². 2 .

[0058] S2, Pre-treatment of the photoelectric glass window surface: The photoelectric glass window is ultrasonically cleaned in isopropanol at a power of 200W and a frequency of 60kHz for 5 minutes. The photoelectric glass window is an irregularly shaped piece. Both the first and second steps of the photoelectric glass window are regular octagons. The second step is set on the first step. The side length of the first step is 100mm and the height is 10mm. The side length of the second step is 50mm and the height is 5mm. The sides of both the first and second steps are blackened and opaque. Before applying the antireflective coating, all areas of the photoelectric glass window that do not require antireflective coating, except for the upper surface of the second step, are protected with high-temperature tape. These areas include the sides and upper surface of the first step and the sides of the second step. The photoelectric glass window is then placed in an atomic layer deposition (ALD) apparatus to deposit a composite film of silicon dioxide and titanium dioxide on the upper surface of the second step of the photoelectric glass window. The total thickness of the two films is 280nm. The film thickness was reduced by 5 nm using chemical mechanical polishing (CMP). The polishing solution was silica sol, and the rotation speed was 150 rpm. After polishing, the surface roughness of the silica film was 0.7 nm, resulting in a photoelectric glass window coated with a composite film of silica and titanium dioxide.

[0059] S3. First, a layer of antireflective adhesive is uniformly spin-coated onto the optoelectronic glass window coated with the composite film layer at a spin coater speed of 5000 rpm, resulting in an antireflective adhesive layer thickness of 300 nm. This is then baked on a hot plate at 130°C for 120 s. Subsequently, a 1000 nm thick layer of I-line photoresist is uniformly spin-coated onto the antireflective adhesive at a spin coater speed of 3000 rpm. Finally, it is pre-baked on a hot plate at 160°C for 120 s to obtain the optoelectronic glass window with the adhesive layer.

[0060] S4. The photoelectric glass window with the adhesive layer is obtained by placing it under a photomask and exposed using a photolithography machine. The light intensity is 2 and the exposure time is 35s. It is then baked under a hot plate at 110℃ for 120s. After returning to room temperature, it is developed in NMD-3 2.38% developer for 60s at a developer temperature of 25℃.

[0061] S5. The side length of the light-transmitting area of ​​the optoelectronic glass is 50mm. The design includes a central region with a side length of 20mm and a groove depth of 150nm, a middle region with a width of 20mm and a groove depth of 100nm, and an edge region with a width of 10mm and a groove depth of 50nm. The product obtained in step S4 is etched in sections. First, the 10mm edge region, the 20mm central region, and the 20mm middle region are etched using plasma. The etching gases are oxygen and sulfur hexafluoride, the etching gas flow rate is 15L / min, the etching time is 25s, and the etching power is 120W. Then, the 10mm edge region is protected with high-temperature tape. Next, the 20mm middle region and the 20mm central region are etched, with an etching gas flow rate of 15L / min, an etching time of 25s, and an etching power of 120W. Finally, the middle region is protected with high-temperature tape again, and the 20mm central region is etched separately, with an etching gas flow rate of 15L / min, an etching time of 25s, and an etching power of 150W.

[0062] S6. Peel off the high-temperature resistant tape from the 10mm edge region and the 20mm middle region of the etched optoelectronic glass window mesh structure obtained in step S5. Then, use a magnetron sputtering device to simultaneously coat the edge region, the middle region and the center region. The coating target is aluminum, the coating time is 100s, the temperature is 160℃, the coating power is 200W and the coating thickness is 200nm.

[0063] S7. Using a resist remover, the anti-reflective adhesive and photoresist on the optoelectronic glass window obtained in S6 are removed, leaving only the plated aluminum in the grid grooves. The resist remover has a power of 400W and a removal time of 15 minutes. Next, it is ultrasonically cleaned with isopropanol for 5 minutes at a power of 500W and a frequency of 60kHz. Finally, it is dried in a vacuum drying oven at 80℃ for 20 minutes.

[0064] S8. Using an ultraviolet spectrometer, the transmittance and sheet resistance of different regions of the photoelectric glass metal mesh window obtained in S7 were tested. The test results showed that the transmittance of the 20mm central region was 86%, the transmittance of the 20mm middle region was 88%, and the transmittance of the 10mm edge region was 90%. The sheet resistance of the central region was 32Ω, the middle region was 68Ω, and the edge region was 93Ω. The transmittance test results are as follows: Figure 4 As shown.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for fabricating a stepped-variable conductive high-transmittance micro / nano grid optoelectronic glass window, characterized in that, Includes the following steps: 1) Photoelectric glass window structure design: The photoelectric glass window has a transmittance ≥85% and a sheet resistance <100Ω / □. Based on this, the groove depth, line width, and period of the grid are designed. T (光电玻璃窗口) %= T (光电玻璃材料) %-(linewidth / period)%; Obtain the network structure; Where T (光电玻璃窗口) % indicates the transmittance of the photoelectric glass window; T (光电玻璃材料) This indicates the transmittance of the photoelectric glass material; linewidth / period indicates the ratio of linewidth to period. 2) Mask fabrication: The mesh structure designed in step 1) is fabricated into a mask; 3) Surface treatment of photoelectric glass window: A certain thickness of antireflective coating is deposited on the photoelectric glass window, and the surface roughness of the antireflective coating is made less than 1nm by chemical mechanical polishing; 4) Fabrication of the structure on the optoelectronic glass window: The anti-reflective adhesive is uniformly spin-coated onto the antireflective film layer obtained in step 3), baked for the first time, then uniformly spin-coated with photoresist, and baked for the second time to obtain optoelectronic glass with adhesive layer; the optoelectronic glass with adhesive layer is placed under a photomask and exposed using a photolithography machine, and the mesh structure is transferred to the optoelectronic glass window through exposure, and the mesh structure designed in step 1) is obtained after development; 5) Transfer of photoelectric glass window structure: The grid structure obtained in step 4) is divided into sections and then etched to obtain a photoelectric glass grid window with stepped groove depth. The groove depth increases or decreases from the center area to the edge area of ​​the photoelectric glass window. 6) Partitioned coating of optoelectronic glass window structure: The area with the deep groove of the stepped groove on the optoelectronic glass grid window is coated with a metal film layer of a certain thickness by magnetron sputtering. Then, the anti-reverse adhesive and photoresist are removed by a resist remover to obtain an optoelectronic glass grid window with a metal layer only in the grid groove; that is, a conductive high-transmittance micro-nano grid optoelectronic glass window.

2. The processing method according to claim 1, characterized in that, The network structure is an interconnected pattern, the linewidth is 300-3000nm, and the period is 3.3um-33um; the photoelectric glass material has a transmittance of ≥94%. The thickness of the metal film is greater than the depth of the etched trench; The mask is prepared by electron beam direct writing, and the substrate for preparing the mask is quartz glass with a low coefficient of thermal expansion.

3. The processing method according to claim 2, characterized in that, In step 3), the photoelectric glass window is ultrasonically cleaned in isopropanol for 5-15 minutes before the antireflection coating is deposited. The cleaned photoelectric glass window is then placed in an atomic layer deposition or chemical vapor deposition device to deposit the antireflection coating on the photoelectric glass window. The ultrasonic cleaning power is 200-300W, and the frequency is 40-80 kHz; The antireflective coating is made of at least one of silicon dioxide, aluminum oxide, titanium dioxide, and hafnium oxide. The thickness of the antireflective coating is 100-300 nm greater than the groove depth of the grid; The thickness of the metal film layer is 50-200 nm greater than the depth of the etching trench; The photoelectric glass window is an irregularly shaped object, including a first step body and a second step body disposed on the first step body. The first step body and the second step body are circular or polygonal in shape. The diameter or side length of the first step body is 20-100mm, the diameter or side length of the second step body is 10-50mm, and the thickness of the photoelectric glass window is 2-20mm.

4. The processing method according to claim 3, characterized in that, The spin coater speed for the anti-reflective adhesive and photoresist is 2000-5000 rpm. The thickness of the anti-reflective adhesive layer is 100-300 nm, and the thickness of the photoresist layer is 300 nm-1000 nm. The temperature of the first baking is 100-130℃, and the baking time is 60-120 s. The temperature of the second baking is 110-160℃, and the baking time is 80-120 s. The light intensity of the exposure is 1.2-3 mW / cm². 2 The exposure time is 20-80s, the baking temperature after exposure is 110-160℃, the baking time is 80-120s, and the developing time is 35-90s.

5. The processing method according to claim 4, characterized in that, In step 5), the etching gas is selected from two or more of oxygen, carbon tetrafluoride, argon, trifluoromethane, sulfur hexafluoride and nitrogen. The flow rate of the etching gas is 2-80 L / min, the power is 40-320 W, and the etching depth is 50 nm-1000 nm.

6. The processing method according to claim 5, characterized in that, The target material for the magnetron sputtering metal film is gold, silver, aluminum, tungsten, or chromium. The temperature during the metal film deposition is 25-160℃, the deposition time is 30-1000s, and the power is 60-500W.

7. The processing method according to claim 6, characterized in that, The adhesive stripper has a power of 300-800W and a stripping time of 10-20 minutes. It is used to remove the anti-reverse adhesive and photoresist on the photoelectric glass mesh window. Then, the photoelectric glass mesh window is placed in a high-purity isopropanol solution for ultrasonic cleaning for 5-10 minutes. The ultrasonic power is 150-500W and the ultrasonic frequency is 40-80kHz. It is then dried in a vacuum oven at a temperature of 80-100℃ for 10-20 minutes.

8. The processing method according to any one of claims 1-7, characterized in that, After the grid structure obtained in step 4) is divided into partitions, it includes a central region, a middle region and an edge region. The middle region is located between the central region and the outer region. The central region is a high-transparency region or a low-transparency region. The edge region is a fully transparent region. The middle region is a low-transparency region or a high-transparency region. The partitioned etching process involves first protecting the fully transparent area with tape, then etching the high-transparency and low-transparency areas. After etching to a certain depth, the low-transparency or high-transparency areas are then protected with tape. The area not protected with tape is then etched to the required groove depth to obtain a photoelectric glass grid window with stepped groove depth.

9. The processing method according to claim 8, characterized in that, Before protecting the fully transparent area with tape, the high-transparency area, low-transparency area, and fully transparent area are simultaneously etched.

10. A stepped-varying conductive high-transmittance micro / nano grid optoelectronic glass window, characterized in that, It is prepared according to the processing method according to any one of claims 1-9.

Images