Method for preparing self-assembled monolayer of silane molecules and multilayer metal oxide thin film structure

Abstract

The application provides a preparation method of a silane molecule self-assembled monolayer film and a multilayer metal oxide film structure. The preparation method of the silane molecule self-assembled monolayer film comprises the following steps: performing activation treatment on a substrate surface; and performing self-assembly on at least part of the activation treatment area by using silane molecules to form a silane molecule self-assembled monolayer film; wherein the silane molecules comprise a hydrophobic chain segment with more than 4 carbon atoms, and the silane molecules do not contain chlorine elements; the substrate surface comprises a metal oxide film layer, and the silane molecule self-assembled monolayer film is at least partially formed on the surface of the metal oxide film layer. Further, on the basis of the preparation method of the silane molecule self-assembled monolayer film, a preparation method of a multilayer metal oxide film structure is provided. Compared with a conventional vacuum deposition process, the method provided by the application has greatly improved operability and convenience, and the production cost is significantly reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to a preparation method of a self-assembled monolayer of silane molecules and a multilayer metal oxide film structure, in particular to a preparation method of a self-assembled monolayer of silane molecules for realizing hydrophobic chemical modification of a metal oxide film surface and a preparation method of a multilayer metal oxide film structure using the self-assembled monolayer of silane molecules, and belongs to the technical field of thin film transistor micro-nano manufacturing. BACKGROUND

[0002] Thin film transistor (TFT) is the core element of pixel driving circuit of various display screens. Metal oxide thin film transistor with metal oxide as semiconductor active layer material has the advantages of high mobility (1-100 cm 2 / (V·s)), high structural uniformity, and transparency in visible light band, and has broad application prospects in transparent display field.

[0003] The metal oxide film in the metal oxide thin film transistor is usually prepared by vacuum deposition process, such as radio frequency sputtering, atomic layer deposition, and pulse laser deposition. However, the vacuum deposition process must provide a vacuum environment, which is high in manufacturing cost and low in production efficiency.

[0004] In recent years, solution method has gradually attracted more and more interests of researchers due to its low cost, easy large-scale manufacturing and patterning. Among them, the surface energy induced directional assembly process based on solution method is concerned due to its simplicity and wide applicability. In the surface energy induced directional assembly process based on solution method, part of the substrate needs to be modified to be hydrophobic. At present, the most commonly used method to realize this hydrophobic modification is to form a hydrophobic self-assembled monolayer by chemisorption of silane molecules.

[0005] Reference document 1 discloses a solution-free self-patterning method for manufacturing a patterned indium gallium zinc oxide thin film transistor. The method forms a hydrophobic surface on a SiO2 dielectric by using polydimethylsiloxane (PDMS) to modify the surface by stamping and heat treatment, then performs UVO treatment, selectively performs surface modification to form a selective wetting area, and finally uses an indium gallium zinc oxide (IGZO) solution to spin-coat on the surface to produce a clear IGZO semiconductor pattern. The method has the advantages of simplicity, rapidness and environmental protection.

[0006] Reference 2 discloses a blade coating process for depositing source, drain and semiconductor layers on a surface energy patterned plastic substrate. The method uses (heptadecafluoro-1,1,2,2-tetrahydrodecyl)trichlorosilane to deposit a hydrophobic self-assembled monolayer on the plastic substrate before exposure to a low-power oxygen plasma, then the ink of the desired material is dragged by a doctor blade, suspended above the substrate, and selectively wet the hydrophilic regions to achieve a highly uniform array. The process is simple and can be used for production because it is compatible with large-area processing and does not require photolithography and stripping.

[0007] Reference 3 discloses a method for preparing a patterned TIPS-pentacene thin film. The method combines solution shear deposition and template solution wetting to prepare a patterned transistor through a TIPS-pentacene thin film, wherein the shear blade is first treated with octadecyltrichlorosilane to form a hydrophobic layer, then UV / ozone treated, and then the TIPS-pentacene solution is applied to the surface of the substrate and shear using a shear blade to deposit TIPS-pentacene to the surface of the substrate to form a pattern. The method is simple, inexpensive and has high mobility.

[0008] It can be seen that the solution-based surface energy-induced directional assembly process of metal oxide thin film has been widely studied in the prior art, but the preparation of multi-layer metal oxide thin film structure using this process is less studied in the prior art. Therefore, the research on the surface energy-induced directional assembly process of metal oxide thin film is not sufficient, and there is room for further development and exploration.

[0009] Reference:

[0010] Reference 1: Kim D-K, Park J-I, Jang J, et al. Expeditious and eco-friendly solution-free self-patterning of sol-gel oxide semiconductor thin films [J]. Materials & Design, 2020, 194: 108949.

[0011] Reference 2: Pierre A, Sadeghi M, Payne M M, et al. All-Printed Flexible Organic Transistors Enabled by Surface Tension-Guided Blade Coating [J]. Advanced Materials, 2014, 26(32): 5722-5727. DOI: 10.1002 / adma.201401520.

[0012] Reference 3: Giri G, Miller E, Bao Z. Selective solution shearing deposition of high performance TIPS-pentacene polymorphs through chemical patterning [J]. Journal of Materials Research, 2014, 29(22): 2615-2624. DOI: 10.1557 / jmr.2014.305. SUMMARY

[0013] Problem to be solved by the invention

[0014] As mentioned above, in the field of metal oxide thin film transistors, the preparation of metal oxide thin films can adopt a surface energy-induced directed assembly process based on solution method, such as the preparation process in reference documents 1-3, which has the advantages of simplicity, low production cost, and large-area production compared to the traditional vacuum deposition process.

[0015] However, none of reference documents 1-3 further describes the possibility of using the method to prepare a multi-layer metal oxide thin film, and there is almost no related research and reports on the preparation of multi-layer metal oxide thin films using the surface energy-induced directed assembly process in the prior art. On the contrary, the preparation of multi-layer metal oxide thin films is usually carried out by deposition method.

[0016] In the further practice of the inventor, it is found that the main reason why the current surface energy-induced directed assembly process cannot realize the preparation of multi-layer metal oxide thin film structure is that the surface of the metal oxide thin film prepared in the previous process needs to be modified to be hydrophobic by generating a self-assembled monolayer of silane molecules, and if the type of silane molecules is not properly selected, the by-products of the chemical reaction in the modification process will corrode the underlying metal oxide, resulting in the destruction of the prepared thin film structure.

[0017] Based on the above research findings, the present application proposes a preparation method of a self-assembled monolayer of silane molecules and a multi-layer metal oxide thin film structure.

[0018] Solution for solving the problem

[0019] [1]. A preparation method of a self-assembled monolayer of silane molecules, comprising the following steps:

[0020] activating the surface of the substrate;

[0021] self-assembling monolayer of silane molecules is formed by self-assembly of silane molecules in at least a part of the activation treatment region;

[0022] wherein the silane molecules include a hydrophobic segment having 4 or more carbon atoms, and the silane molecules do not include a chlorine element;

[0023] the substrate surface includes a metal oxide thin film layer, and the self-assembling monolayer of silane molecules is formed at least partially on the surface of the metal oxide thin film layer.

[0024] [2]. The production method according to [1], wherein the self-assembling monolayer of silane molecules has a contact angle of 95° or more.

[0025] [3]. The production method according to [1] or [2], wherein the hydrophobic segment is selected from a hydrocarbon group or a hydrocarbon group substituted with a substituent, and optionally, the substituent includes a fluorine-containing group.

[0026] [4]. The production method according to any one of [1] to [3], wherein the silane molecules are one or more of a combination of trimethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, trimethoxy(lH, lH, 2H, 2H-tridecafluoro-n-octyl)silane, trimethoxy(lH, lH, 2H, 2H-heptadecafluorodecyl)silane, octadecyltrimethoxysilane, hexadecyltrimethoxysilane, dodecyltrimethoxysilane, and octyltrimethoxysilane, triethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, triethoxy-lH, lH, 2H, 2H-tridecafluoro-n-octylsilane, lH, lH, 2H, 2H-perfluorodecyltriethoxysilane, octadecyltriethoxysilane, hexadecyltriethoxysilane, dodecyltriethoxysilane, hexyltriethoxysilane, and butyltriethoxysilane.

[0027] [5]. The production method according to any one of [1] to [4], wherein the activation treatment is one of a plasma treatment, a Piranha solution immersion, an ultraviolet light treatment, and an ultraviolet-ozone (UVO) treatment.

[0028] [6]. The production method according to any one of [1] to [5], wherein the self-assembly method is one or more of a solution immersion method, a solution coating method, a solution pull-out method, and a vapor phase heat treatment method.

[0029] [7]. A production method of a multilayer metal oxide thin film structure, which includes the production method of a self-assembling monolayer of silane molecules according to any one of [1] to [6].

[0030] [8]. The production method according to [7], which includes the following steps:

[0031] forming a silane molecule self-assembled monolayer film on the surface of the substrate by the preparation method according to any one of [1] to [6];

[0032] forming another metal oxide thin film layer on the region of the surface of the metal oxide thin film layer of the substrate where the silane molecule self-assembled monolayer film is not present.

[0033] [9]. The preparation method according to [8], wherein the forming method of the another metal oxide thin film layer comprises one or more of a solution spin coating method, a solution blade coating method, and a solution immersion method.

[0034]

[10] . The preparation method according to [7] or [8], wherein a multi-layer stacked metal oxide thin film structure is obtained by performing the method of [7] or [8] multiple times.

[0035] Effects of the invention

[0036] Through the implementation of the above technical solutions, the present application can obtain the following technical effects:

[0037] 1) Unlike the conventional preparation of a multi-layer metal oxide thin film structure which usually uses a vacuum deposition process, the present application provides a new process which has greatly improved operability and convenience and significantly reduced production cost relative to the vacuum deposition process;

[0038] 2) The present application uses a silane molecule self-assembled monolayer film to perform controllable patterning on the metal oxide thin film again, and can further form another metal oxide thin film on the hydrophilic region, thereby preparing a multi-layer metal oxide thin film structure;

[0039] 3) In the process of forming a silane molecule self-assembled monolayer film on the metal oxide thin film of the present application, by controlling the type of silane molecule, the process will not damage the underlying metal oxide thin film structure, thereby ensuring the reliability and feasibility of forming a multi-layer structure.

[0040] 4) The preparation method of the silane molecule self-assembled monolayer film provided by the present application is simple and has environmental advantages. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 Optical microscope image after generating 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane self-assembled monolayer film on the surface of the patterned zinc oxide thin film;

[0042] Figure 2 Optical microscope image after generating trimethoxy(1H, 1H, 2H, 2H-nonafluorohexyl)silane self-assembled monolayer film on the surface of the patterned zinc oxide thin film;

[0043] Figure 3 Optical micrograph of a patterned zinc oxide film surface after formation of a trichlorosilane self-assembled monolayer film thereon;

[0044] Figure 4 Optical micrograph of a patterned zinc oxide film surface after formation of a triethoxyl(1H, 1H, 2H, 2H-nonafluorohexyl)silane self-assembled monolayer film thereon;

[0045] Figure 5 Optical micrograph of a multilayer patterned metal oxide film structure prepared by a surface energy induced directed assembly process;

[0046] Figure 6 Optical micrograph of a patterned zinc oxide film surface after formation of a trichlorosilane self-assembled monolayer film thereon. DETAILED DESCRIPTION

[0047] Hereinafter, the content of the present application will be described in detail. The description of the technical features described below is based on representative embodiments, specific examples of the present application, but the present application is not limited to these embodiments, specific examples. Note that:

[0048] In the present specification, a numerical range indicated by "numerical value A to numerical value B" means a range including the end point numerical values A and B.

[0049] In the present specification, a numerical range indicated by "above" or "below" means a numerical range including the present number.

[0050] In the present specification, the meaning indicated by "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0051] In the present specification, "optionally" or "optional" means that a certain substance, component, execution step, applied condition, and the like are used or not used.

[0052] In the present specification, "room temperature" or "ambient temperature" means an indoor environmental temperature of "23 ± 2°C", and, unless otherwise specified, the "viscosity" of the present application is the viscosity at this temperature.

[0053] In the present specification, the unit name used is the international standard unit name, and, unless otherwise specified, "%" used means a weight or mass percentage content.

[0054] In the present specification, "substantially" means that the standard deviation from a theoretical model or theoretical data is within a numerical range of 5%, preferably 3%, and more preferably 1%.

[0055] In this specification, use of the terms "comprise" and / or "comprising" will be understood to enable the presence of features, steps, operations, devices, components, and / or combinations thereof described herein, but does not preclude the presence or addition of one or more other features, steps, operations, devices, components, and / or combinations thereof.

[0056] In this specification, references to "some specific / preferred embodiments", "other specific / preferred embodiments", "embodiments", etc. mean that the particular feature(s) (e.g. feature, structure, property and / or characteristic) described is included in at least one embodiment described herein, and can or can not be present in other embodiments. In addition, it should be understood that the described features can be combined in any suitable manner in various embodiments.

[0057] The present application provides a preparation method of a silane molecule self-assembled monolayer film, and a preparation method of a multilayer metal oxide film structure based on the preparation method of the silane molecule self-assembled monolayer film. The present application is based on the following insights:

[0058] It has been found that, compared with the traditional vacuum deposition process, the surface energy induced directional assembly process based on the solution method has the advantages of simple process, low cost, and easy large-scale production, etc. However, the current surface energy induced directional assembly process cannot realize the preparation of a multilayer metal oxide film structure. Based on this, it has been found that the main reason why the current surface energy induced directional assembly process cannot realize the preparation of a multilayer metal oxide film structure is that the surface of the metal oxide film prepared in the previous process needs to be modified to be hydrophobic by generating a silane molecule self-assembled monolayer film, and in the process of hydrophobic modification, the film structure will be damaged by some chemicals produced by the chemical reaction of the silane molecule. Further, the inventors have found that when the silane molecule contains chlorine elements, the chemical reaction in the modification process will produce by-product hydrogen chloride to corrode the underlying metal oxide, so that the prepared film structure is damaged. Therefore, the present application controls the type of silane molecule so that the process of forming a silane molecule self-assembled monolayer film on the metal oxide film does not damage the underlying metal oxide film structure, thereby ensuring the reliability and feasibility of forming a multilayer structure. Further, the present application forms a silane molecule self-assembled monolayer film on the metal oxide film to perform controllable patterning again, and can further form another layer of metal oxide film on the hydrophilic region, thereby preparing a multilayer metal oxide film structure.

[0059] <First aspect>

[0060] The first aspect of the present application provides a preparation method of a silane molecule self-assembled monolayer film, comprising the following steps:

[0061] activating the surface of the substrate;

[0062] Self-assembly of silane molecules to form a self-assembled monolayer of silane molecules in at least a part of the activation treatment region.

[0063] (Base)

[0064] The kind of the base of the present application is not particularly limited in principle. It can be an inorganic material, an organic material, or a composite of an inorganic material and an organic material.

[0065] In some specific embodiments, the inorganic material can be selected from one or more of carbon-based inorganic materials, silicon-based inorganic materials, metal oxide materials, and more specifically, can be selected from one or more of silicon wafer, silicon oxide, sapphire, glass, quartz, ITO, and the like.

[0066] In other specific embodiments, the organic material can be selected from various polymer materials, and more specifically, can be selected from one or more of polyimide materials, polyester materials, polycarbonate materials, and the like, and preferably, can be selected from polyester materials such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and the like, polycarbonate materials having an aryl structural unit, and the like.

[0067] Further, the base of the present application can also be a composite base formed of the above various materials, for example, can be a multi-layer structure composite.

[0068] In addition, the base of the present application can be flexible or rigid. Also, the shape of the base material is not particularly limited in principle, for example, can be flat, thin film, and the like.

[0069] The base of the present application has a metal oxide thin film layer on the surface thereof, wherein the metal oxide can be a metal oxide commonly used as a semiconductor in the art, for example, zinc oxide (ZnO), indium oxide (In2O3), gallium oxide (Ga2O3), tin oxide (SnO), indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), indium gallium zinc oxide (IGZO), and the like.

[0070] The activation treatment and the self-assembly of silane molecules described below in the present application occur at least partially on the surface of the metal oxide thin film layer. Also, the self-assembled monolayer of silane molecules prepared by the preparation method of the present application does not have a damaging effect on the oxide thin film layer on the surface of the base, and can achieve a non-destructive hydrophobic effect.

[0071] (Activation treatment)

[0072] The present application is advantageous for the subsequent self-assembly by performing the activation treatment on the surface of the base.

[0073] In some preferred embodiments, the substrate surface can be subjected to a cleaning treatment before the activation treatment, for example, the surface can be treated with an acidic, oxidizing or the like liquid.

[0074] As for the activation treatment method, the present application is not particularly limited, and any activation treatment method commonly used in the art can be used, for example, plasma treatment, Piranha solution immersion, ultraviolet light treatment, ultraviolet-ozone (UVO) treatment, etc., as long as the substrate surface can be activated.

[0075] In some specific embodiments, the activation treatment is such that at least part of the surface of the metal oxide thin film layer on the substrate is subjected to the activation treatment.

[0076] (Silane molecule self-assembly)

[0077] In the present application, a silane molecule is self-assembled on at least part of or the entire activation treatment area to form a silane molecule self-assembled monolayer film, thereby achieving the hydrophobic modification of the substrate surface.

[0078] Silane molecules

[0079] As for the silane molecule, it includes a hydrophobic segment having a carbon atom number of 4 or more, for example, 9 or more, 12 or more, 16 or more, etc., for example, a hydrophobic segment having 4 to 26 carbon atoms, and the silane molecule does not contain chlorine element. Through the inventors' research, it is found that if the silane molecule contains chlorine element, the chemical reaction during the modification process will produce by-product hydrogen chloride to corrode the underlying metal oxide, so that the thin film structure is destroyed. Therefore, using a silane molecule that does not contain chlorine element, especially a silane molecule that does not contain chlorine element directly bonded to silicon element, for self-assembly is beneficial to protect the structural integrity of the underlying metal oxide thin film.

[0080] In some specific embodiments, the silane molecule has one hydrophobic segment and three alkoxy groups. Preferably, the alkoxy group is methoxy or ethoxy.

[0081] In other specific embodiments, the hydrophobic segment is selected from a (carbon atom number 4 to 26 carbon atom) hydrocarbon group or a substituted hydrocarbon group substituted with a substituent group. In order to further improve the hydrophobicity of the silane molecule self-assembled monolayer film, the substituent group can include a fluorine-containing group.

[0082] In some preferred embodiments, the silane molecule is one or more of a combination of trimethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, trimethoxy(lH, lH, 2H, 2H-tridecafluoro-n-octyl)silane, trimethoxy(lH, lH, 2H, 2H-heptadecafluorodecyl)silane, octadecyltrimethoxysilane, hexadecyltrimethoxysilane, dodecyltrimethoxysilane, and octyltrimethoxysilane, triethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, triethoxy-lH, lH, 2H, 2H-tridecafluoro-n-octylsilane, lH, lH, 2H, 2H-perfluorodecyltriethoxysilane, octadecyltriethoxysilane, hexadecyltriethoxysilane, dodecyltriethoxysilane, hexyltriethoxysilane, and butyltriethoxysilane.

[0083] For hydrophobicity, water contact angle under normal temperature condition can be used for characterization. In the present application, the water contact angle of the self-assembled monolayer of the silane molecule is 95° or more, preferably 100° or more, more preferably 120° or more, further preferably 140° or more, and particularly preferably 160° or more or 170° or more.

[0084] Self-assembly

[0085] For the self-assembly method, liquid phase method or gas phase method commonly used in the art can be used for the self-assembly of the silane molecule. In some specific embodiments, the liquid phase method is one of solution immersion method, solution coating method, solution pulling method, etc., and the gas phase method is gas phase heat treatment method, etc.

[0086] In some specific embodiments, the solution immersion method is to immerse the activated substrate in an organic solvent containing the silane molecule, to clean the immersed substrate with an organic solvent and optionally to perform drying treatment. In some preferred embodiments, the immersion temperature is 25-200°C; the immersion time is 0.5-10h; and the cleaning time is 30-300s.

[0087] In some specific embodiments, the solution coating method is to uniformly coat the organic solution containing the silane molecule on the surface of the substrate by using a coating method, to perform heat treatment on the coated substrate, to clean the heat-treated substrate with an organic solvent and optionally to perform drying treatment. In some preferred embodiments, the coating method includes but is not limited to:

[0088] dropping the organic solution containing the silane molecule on the surface of the activated substrate, and using a rotation speed of 1000r / min-8000r / min for spin coating;

[0089] The organic solution containing the silane molecule is dropped on the surface of the activated substrate, and is scraped by a doctor blade or a wire bar at a speed of 100 μm / s to 1,000,000 μm / s.

[0090] The organic solution containing the silane molecule is dropped in a slit coater, and the coating head or the substrate is moved at a speed of 100 μm / s to 1,000,000 μm / s.

[0091] The coating time is preferably 10 to 60 seconds; the heating temperature of the coated substrate is 50 to 200°C; the heating time of the coated substrate is 5 to 30 minutes; and the cleaning time is 30 to 300 seconds.

[0092] In some specific embodiments, the solution pulling method is to immerse the activated substrate in the organic solution containing the silane molecule, to vertically pull out the immersed substrate from the solution, to heat the pulled-out substrate, to clean the heated substrate with the organic solution, and to optionally dry the cleaned substrate. In some preferred embodiments, the immersion time is more than 10 seconds; the pulling speed is 100 to 1,000,000 μm / s; the heating temperature of the pulled-out substrate is preferably 50 to 200°C; the heating time of the pulled-out substrate is preferably 5 to 30 minutes; and the cleaning time is 30 to 300 seconds.

[0093] As for the selection of the organic solvent, the present application is not particularly limited, and the organic solvent commonly used in the art can be used, such as ethanol, chloroform, toluene, acetone, ethylene glycol methyl ether, etc. As for the amount of the organic solvent, the volume fraction of the silane molecule in the organic solution containing the silane molecule is preferably 0.1% to 10%.

[0094] In some specific embodiments, the gas phase heat treatment method is to place the activated substrate in a vessel, to drop the liquid silane molecule around the substrate, to cover and heat. In some preferred embodiments, the amount of the liquid silane molecule is 5 to 80 μL, preferably 20 to 40 μL, based on the diameter of the substrate of 100 mm; the heating temperature is 100 to 300°C; and the heating time is 3 to 30 minutes.

[0095] As for the selection of the vessel, the present application is not particularly limited, and the vessel commonly used in the art can be used, such as a glass culture dish, a vacuum glass box, etc.

[0096] <Second Aspect>

[0097] The second aspect of the present application provides a preparation method of a multilayer oxide thin film structure, wherein the preparation method of the silane molecule self-assembled monolayer film according to the <First Aspect> is included.

[0098] Specifically, the method for preparing the multilayer oxide thin film structure comprises the following steps:

[0099] forming a self-assembled monolayer of silane molecules on the substrate surface by the method for preparing as described in the <first aspect>;

[0100] forming an additional metal oxide thin film layer on the substrate surface in the region where the self-assembled monolayer of silane molecules is not present on the surface of the metal oxide thin film layer.

[0101] For the region of the substrate surface where the self-assembled monolayer of silane molecules is not present on the surface of the metal oxide thin film layer, the hydrophilic treatment can be optionally performed to impart hydrophilicity to these regions before forming the additional metal oxide thin film layer.

[0102] For the hydrophilicity as described in the present application, it refers to the contact angle of water on the surface being less than 90° at room temperature, preferably less than 70°, more preferably less than 50°, further preferably less than 30°, and especially preferably less than 15° or 10°.

[0103] The method for the hydrophilic treatment is not particularly limited and the method commonly used in the art can be used, for example, the method that can be used includes oxygen plasma treatment, Piranha solution immersion, ultraviolet (UV) light treatment, and the like to impart hydrophilicity to the substrate surface.

[0104] It is to be noted that the hydrophilic treatment can be performed before or after the formation of the self-assembled monolayer of silane molecules.

[0105] In some specific embodiments, the hydrophilic treatment method can be used first to impart hydrophilicity to the substrate with the metal oxide thin film layer, spin coating photoresist on the substrate, using photolithography technology to produce a photoresist mask, and then forming a self-assembled monolayer of silane molecules on the substrate surface to impart hydrophobicity to the region not covered by the photoresist mask.

[0106] In other specific embodiments, the self-assembled monolayer of silane molecules can be formed first on the substrate surface with the metal oxide thin film layer to impart hydrophobicity to these substrates, and then the metal mask and the hydrophilic treatment method are used to impart hydrophilicity to the uncovered region of the substrate. For the additional metal oxide thin film layer, the metal oxide therein can be the same as or different from the metal oxide in the metal oxide thin film contained in the substrate surface.

[0107] Further, for the forming method of the additional metal oxide thin film layer, although deposition method can also be used, by the above technical solution of the present application, solution adsorption method can be successfully implemented, and typical solution adsorption method can be one or more of, for example, solution spin coating method, solution blade coating method, and solution immersion method.

[0108] In some specific embodiments, the above preparation method is performed multiple times to obtain a multi-layer stacked metal oxide thin film structure.

[0109] Examples

[0110] The embodiments of the present application will be described in detail below with reference to examples, but those skilled in the art will understand that the following examples are only used to illustrate the present application and should not be regarded as limiting the scope of the present application. If the specific conditions are not specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be obtained commercially.

[0111] Example 1

[0112] (1) A silicon oxide wafer with an oxide layer thickness of 100 nm was used as a substrate;

[0113] (2) The substrate was subjected to oxygen plasma treatment at a power of 70 W, an oxygen flow rate of 100 sccm, and a treatment time of 3 min;

[0114] (3) An NR9-3000PY negative photoresist was used for photolithography and development to prepare a photoresist pattern;

[0115] (4) The substrate with the photoresist pattern was subjected to oxygen plasma treatment at a power of 70 W, an oxygen flow rate of 100 sccm, and a treatment time of 3 min;

[0116] (5) The sample was placed in a glass vacuum box, 20 μL of 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane was added dropwise, vacuum was applied, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was removed;

[0117] (6) The sample was immersed in a 0.5M indium nitrate solution in ethylene glycol monomethyl ether for 1 min, and then the sample was pulled out of the solution at a speed of 5000 μm / s and dried for 3 min;

[0118] (7) The dried sample was placed on a 150°C hot plate for heating for 5 min, and then placed on a 400°C hot plate for heating for 1 h to obtain a substrate with a patterned metal oxide thin film;

[0119] (8) Oxygen plasma treatment was performed on the substrate with metal oxide film, the treatment power was 500 W, the oxygen flow was 100 sccm, and the treatment time was 3 min;

[0120] (9) The sample was placed in a glass vacuum box, 20 μL of 1H, 1H, 2H, 2H- perfluorodecyltriethoxysilane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out, as shown in Figure 1

[0121] Example 2

[0122] (1) A silicon oxide wafer with an oxide layer thickness of 100 nm was used as a substrate;

[0123] (2) Oxygen plasma treatment was performed on the substrate, the treatment power was 70 W, the oxygen flow was 100 sccm, and the treatment time was 3 min;

[0124] (3) NR9-3000PY negative photoresist was used for photolithography and development to prepare a photoresist pattern;

[0125] (4) Oxygen plasma treatment was performed on the substrate with the photoresist pattern, the treatment power was 70 W, the oxygen flow was 100 sccm, and the treatment time was 3 min;

[0126] (5) The sample was placed in a glass vacuum box, 20 μL of trimethoxy(1H, 1H, 2H, 2H- nonafluorohexyl) silane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out;

[0127] (6) The sample was immersed in a 0.5M indium nitrate ethylene glycol monomethyl ether solution for 1 min, and then the sample was pulled out of the solution at a speed of 5000 μm / s and dried for 3 min;

[0128] (7) The dried sample was placed on a 150°C hot plate for heating for 5 min, and then placed on a 400°C hot plate for heating for 1 h to obtain a substrate with a patterned metal oxide film;

[0129] (8) Oxygen plasma treatment was performed on the substrate with metal oxide film, the treatment power was 500 W, the oxygen flow was 100 sccm, and the treatment time was 3 min;

[0130] (9) The sample was placed in a glass vacuum box, 20 μL of trimethoxy(1H, 1H, 2H, 2H- nonafluorohexyl) silane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out, as shown in Figure 2

[0131] ​​Example 3

[0132] (1) A silicon oxide wafer with an oxide layer thickness of 100 nm was used as a substrate;

[0133] (2) The substrate was subjected to oxygen plasma treatment at a power of 70 W and an oxygen flow rate of 100 sccm for 3 min;

[0134] (3) A photoresist pattern was prepared by photoetching and developing using NR9-3000PY negative photoresist;

[0135] (4) The substrate with the photoresist pattern was subjected to oxygen plasma treatment at a power of 70 W and an oxygen flow rate of 100 sccm for 3 min;

[0136] (5) The sample was placed in a glass vacuum box, 20 μL of trimethoxy(1H, 1H, 2H, 2H-heptadecafluorodecyl)silane was added dropwise, vacuum was applied, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was removed;

[0137] (6) The sample was immersed in a 0.5M indium nitrate solution in ethylene glycol monomethyl ether for 1 min, and then the sample was pulled out of the solution at a speed of 5000 μm / s and dried for 3 min;

[0138] (7) The dried sample was placed on a 150°C hot plate for heating for 5 min, and then placed on a 400°C hot plate for heating for 1 h, to obtain a substrate with a patterned metal oxide film;

[0139] (8) The substrate with the metal oxide film was subjected to oxygen plasma treatment at a power of 500 W and an oxygen flow rate of 100 sccm for 3 min;

[0140] (9) The sample was placed in a glass vacuum box, 20 μL of trimethoxy(1H, 1H, 2H, 2H-heptadecafluorodecyl)silane was added dropwise, vacuum was applied, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was removed, as shown in Figure 3 .

[0141] Example 4

[0142] (1) A silicon oxide wafer with an oxide layer thickness of 100 nm was used as a substrate;

[0143] (2) The substrate was subjected to oxygen plasma treatment at a power of 70 W and an oxygen flow rate of 100 sccm for 3 min;

[0144] (3) A photoresist pattern was prepared by photoetching and developing using NR9-3000PY negative photoresist;

[0145] (4) Oxygen plasma treatment was performed on the substrate with photoresist pattern, the treatment power was 70 W, the oxygen flow rate was 100 sccm, and the treatment time was 3 min;

[0146] (5) The sample was placed in a glass vacuum box, 20 μL of triethoxy(lH, 1H, 2H, 2H- nonafluorohexyl) silane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out;

[0147] (6) The sample was immersed in a 0.5M indium nitrate ethylene glycol monomethyl ether solution for 1 min, and then the sample was pulled out of the solution at a speed of 5000 μm / s and dried for 3 min;

[0148] (7) The dried sample was placed on a 150°C hot plate for heating for 5 min, and then placed on a 400°C hot plate for heating for 1 h, to obtain a substrate with a patterned metal oxide film;

[0149] (8) Oxygen plasma treatment was performed on the substrate with metal oxide film, the treatment power was 500 W, the oxygen flow rate was 100 sccm, and the treatment time was 3 min;

[0150] (9) The sample was placed in a glass vacuum box, 20 μL of triethoxy(lH, 1H, 2H, 2H- nonafluorohexyl) silane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out, as shown in Figure 4 .

[0151] Example 5

[0152] (1) A silicon oxide wafer with an oxide layer thickness of 100 nm was used as a substrate;

[0153] (2) Oxygen plasma treatment was performed on the substrate, the treatment power was 70 W, the oxygen flow rate was 100 sccm, and the treatment time was 3 min;

[0154] (3) An NR9-3000PY negative photoresist was used for photolithography and development to prepare a photoresist pattern;

[0155] (4) Oxygen plasma treatment was performed on the substrate with photoresist pattern, the treatment power was 70 W, the oxygen flow rate was 100 sccm, and the treatment time was 3 min;

[0156] (5) The sample was placed in a glass vacuum box, 20 μL of triethoxy(lH, 1H, 2H, 2H- nonafluorohexyl) silane was added dropwise, vacuum was drawn, and then the vacuum box was placed on a 200°C hot plate for heating for 10 min, and the sample was taken out;

[0157] (6) immerse the sample in 0.5M indium nitrate in ethylene glycol monomethyl ether solution, soak for 1 min, then pull the sample out of the solution at a speed of 5000 μm / s, dry for 3 min;

[0158] (7) place the dried sample on a 150°C hot plate for 5 min, then place it on a 400°C hot plate for 1 h to obtain a substrate with a patterned metal oxide film;

[0159] (8) repeat steps (1)-(7) three times on the same substrate to obtain a multi-layer patterned metal oxide film structure, as shown in Figure 5 .

[0160] Comparative Example 1

[0161] (1) take a silicon oxide wafer with an oxide layer thickness of 100 nm as a substrate;

[0162] (2) perform oxygen plasma treatment on the substrate, with a treatment power of 70 W, an oxygen flow rate of 100 sccm, and a treatment time of 3 min;

[0163] (3) perform photolithography and development on the substrate using NR9-3000PY negative photoresist to prepare a photoresist pattern;

[0164] (4) perform oxygen plasma treatment on the substrate with the photoresist pattern, with a treatment power of 70 W, an oxygen flow rate of 100 sccm, and a treatment time of 3 min;

[0165] (5) place the sample in a glass vacuum box, add 20 μL of trichloro(1H,1H,2H,2H-tridecafluoro-n-octyl)silane, vacuumize, and then place the vacuum box on a 200°C hot plate for 10 min, and remove the sample;

[0166] (6) immerse the sample in 0.5M indium nitrate in ethylene glycol monomethyl ether solution, soak for 1 min, then pull the sample out of the solution at a speed of 5000 μm / s, dry for 3 min;

[0167] (7) place the dried sample on a 150°C hot plate for 5 min, then place it on a 400°C hot plate for 1 h to obtain a substrate with a patterned metal oxide film;

[0168] (8) perform oxygen plasma treatment on the substrate with the metal oxide film, with a treatment power of 500 W, an oxygen flow rate of 100 sccm, and a treatment time of 3 min;

[0169] (9) Put the sample into a glass vacuum box, drop 20 μL of trichloro(1H, 1H, 2H, 2H-tridecafluoro-n-octyl)silane, vacuumize, then put the vacuum box on a 200℃ hot plate to heat for 10 min, take out the sample, and cool it to room temperature, as shown in Figure 6

[0170] Figures 1-6 It can be seen that the present application overcomes the problem that the substrate film structure is destroyed in the surface energy induced directed assembly process based on the solution method by controlling the type of silane molecules. The silane molecule self-assembled film prepared by the preparation method of the present application can realize the hydrophobic effect without destroying the substrate surface oxide film, and a multilayer metal oxide film structure is successfully prepared by using the silane molecule self-assembled monolayer film, and compared with the traditional vacuum deposition process, the preparation cost of the present application is only one tenth of that of the traditional vacuum deposition process, so the present application provides a new process which has greatly improved operability and convenience and significantly reduced production cost compared with the vacuum deposition process.

[0171] It should be noted that although the technical solutions of the present application are introduced by specific examples, those skilled in the art can understand that the present application should not be limited thereto.

[0172] The above has described various embodiments of the present application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles, practical application or technical improvement in the market of the embodiments, or to enable other ordinary skilled persons in the art to understand the embodiments disclosed herein.​​

Claims

1. A method for preparing a self-assembled monolayer of silane molecules, comprising the steps of: activating a surface of a substrate; self-assembling silane molecules on at least a portion of the activated surface to form a self-assembled monolayer of silane molecules; wherein the silane molecules do not comprise chlorine; and the silane molecules are one or more of a combination of trimethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, trimethoxy(lH, lH, 2H, 2H-tridecafluoro-n-octyl)silane, trimethoxy(lH, lH, 2H, 2H-heptadecafluorodecyl)silane, octadecyltrimethoxysilane, hexadecyltrimethoxysilane, dodecyltrimethoxysilane, and octyltrimethoxysilane, triethoxy(lH, lH, 2H, 2H-nonafluorohexyl)silane, triethoxy-lH, lH, 2H, 2H-tridecafluoro-n-octylsilane, lH, lH, 2H, 2H-perfluorodecyltriethoxysilane, octadecyltriethoxysilane, hexadecyltriethoxysilane, dodecyltriethoxysilane, hexyltriethoxysilane, and butyltriethoxysilane; the surface of the substrate comprises a metal oxide thin film layer, and the self-assembled monolayer of silane molecules is formed at least partially on the surface of the metal oxide thin film layer.

2. The production method according to claim 1, characterized by, the self-assembled monolayer of silane molecules has a contact angle of 95° or more.

3. The production method according to claim 1 or 2, characterized by, the activation treatment is one of plasma treatment, Piranha solution immersion, ultraviolet light treatment, and ultraviolet-ozone treatment.

4. The production method according to claim 1 or 2, characterized by, the self-assembly method is one or more of solution immersion, solution coating, solution pulling, and vapor phase heat treatment.

5. A method of fabricating a multilayer metal oxide thin film structure, characterized by, a method for preparing a self-assembled monolayer of silane molecules according to any one of claims 1 to 4.

6. The production method according to claim 5, wherein a method for preparing a self-assembled monolayer of silane molecules according to any one of claims 1 to 4. forming a self-assembled monolayer of silane molecules on the surface of the substrate according to the method for preparing a self-assembled monolayer of silane molecules according to any one of claims 1 to 4; forming an additional metal oxide thin film layer on a region of the surface of the substrate where the self-assembled monolayer of silane molecules is not present on the surface of the metal oxide thin film layer.

7. The preparation method according to claim 6, characterized in that, the method for forming the additional metal oxide thin film layer comprises one or more of solution spin coating, solution blade coating, and solution immersion.

8. The production method according to claim 5 or 6, characterized by, forming a multilayered metal oxide thin film structure by performing the method of claim 5 or 6 multiple times.

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