Method for patterning substrate, method for forming microstructure on substrate, and method for fabricating fluidic device

Abstract

According to one embodiment of the present disclosure, provided is a method for patterning a substrate. In some embodiments, the method comprises: patterning a hydrophobic film formed on a surface of a substrate; applying a target material; and oxidizing at least the surface of the applied target material. In some embodiments, the method further comprises removing the hydrophobic film from the substrate.

Description

Methods for patterning a substrate, methods for forming microstructures on a substrate, and methods for manufacturing fluidic devices.

[0001] The present disclosure relates to methods for patterning substrates, methods for forming microstructures on substrates, and methods for manufacturing fluidic devices.

[0002] In fields using microfabrication techniques, including biotechnology and semiconductors, microstructures or structures are formed on the surface of a substrate such as a wafer. Such structures are formed partially or discretely on the surface of the substrate. Other portions of the substrate surface are not formed with microstructures, leaving the surface of the substrate substantially exposed.

[0003] However, in many cases, as a result of the microfabrication or its working steps, unwanted structures or substances are formed or attached to the exposed substrate surface, such as processing debris, particle or chemical contaminants, growth or formation of non-specific substances, etc. In some cases, it is desirable to maintain or restore the surface of the substrate on which the microstructures are not formed (which may be the surface of the original substrate or the surface of a film or layer formed on the surface of the original substrate) as clean as possible.

[0004] One example is a fluidic device that contains a microstructure within a flow channel. To position the microstructure within the flow channel, the microstructure is formed on the surface of a substrate, and a cover is then attached to the surface of the substrate. However, the substrate surface to which the cover is attached must be free of microstructures. The presence of unwanted or erroneously formed microstructures, particles, or other contaminants can interfere with the adhesion between the substrate surface and the cover, potentially compromising the hermeticity of the fluid contained within.

[0005] It is desirable to have a method for avoiding the formation or deposition of unwanted structures or materials, such as processing debris, particulate or chemical contaminants, or the growth or formation of non-specific materials, when performing processes such as patterning or forming microstructures on a substrate.

[0006] According to an embodiment of the present disclosure, a method for patterning a substrate is provided, in some embodiments, the method comprises patterning a hydrophobic film formed on a surface of the substrate, applying a target material, and oxidizing at least a surface of the applied target material.

[0007] In some embodiments, the method further comprises removing the hydrophobic film from the substrate.

[0008] Substrate: As used herein, "substrate" generally refers to any substrate or material surface formed on a substrate upon which film processing is performed during a manufacturing process. For example, substrate surfaces that can undergo processing include silicon (Si), silicon oxide (SiO ２ Examples of substrate surfaces include semiconductor materials or materials commonly used in semiconductor processing. Substrate surfaces include other materials, such as metals, metal oxides, metal alloys, and other conductive materials, depending on the application. Substrate surfaces include polymeric materials. Oxides, lipids, and other components may be present on the substrate surface at the atomic or microscopic level. Substrates include, but are not limited to, semiconductor wafers such as silicon wafers, glass wafers, and polymeric films. Substrates may be subjected to pretreatment processes to polish, etch, reduce, oxidize, hydroxylate, anneal, clean, and / or bake the substrate surface. Substrate surfaces may have these materials as their basic constituents and may have impurities or surface layers, for example, resulting from handling in air or a clean room environment.

[0009] In some embodiments, the substrate surface may be partially or entirely hydrophobic. In some embodiments, the substrate surface may be partially or entirely hydrophilic.

[0010] The surface of the substrate may be substantially flat. The surface of the substrate may have a flat surface. The surface of the substrate may be flat after at least the hydrophobic film is removed. The surface of the substrate may be bonded to a member defining a flow path, thereby fluidically sealing the flow path.

[0011] The substrate surface may have a surface roughness of any of or less than 5, 4, 3, 2, 0.5, 0.4, 0.3, 0.2, 0.1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1 nm Ra, etc. The substrate surface may have the surface roughness of a commercially available or industrially used substrate. For example, a commercially available silicon substrate, glass substrate, or polymer substrate or film may be used.

[0012] <Hydrophobic film> As used herein, the term "hydrophobic film" refers to a film made of a material having hydrophobic properties (hydrophobic material, the same applies hereinafter) or having a hydrophobic material on its surface. The hydrophobic film may contain a fluorine compound or a resin. The hydrophobic film may be a so-called fluororesin film.

[0013] The hydrophobic material may be selected from the group consisting of fluorinated polymers, perfluorinated polymers, silicone polymers, and mixtures thereof. For example, the hydrophobic material may be an amorphous fluoropolymer (commercially available examples include the CYTOP® series manufactured by AGC Chemicals, having one of the following terminal functional groups: A type: -COON, M type: -CONH-Si(OR), or S type: -CF). ３ ); polytetrafluoroethylene (commercially available examples include TEFLON® manufactured by Chemours); parylene; fluorinated hydrocarbons; fluoroacrylic copolymers (commercially available examples include FLUOROPEL® manufactured by Cytonix); fluorosilanes (e.g., trichloro(1H,1H,2H,2H-perfluorooctyl)silane (PFOTS); perfluorodecyltrichlorosilane (FDTS), etc.); plasma-deposited fluorocarbons; polydimethylsiloxanes; other siloxanes; hydrophobic hydrocarbons such as 1-heptadecyne, or mixtures thereof.

[0014] The hydrophobic material may be applied to at least a portion or the entire surface of the substrate. The hydrophobic material may be applied to the substrate surface by a dry or wet method. For example, the hydrophobic material may be dropped onto the substrate surface in the form of a solution and spin-coated, followed by drying, heat treatment, or baking.

[0015] In some embodiments, the hydrophobic film formed on the substrate surface is patterned. In some embodiments, the hydrophobic film may be patterned using photolithography techniques. A resist is applied to the surface of the plastic film by spin coating or spraying, and the resist is pre-baked, exposed, and developed. This patterning of the resist occurs. The hydrophobic film is exposed where the resist has been removed. After development, processes such as rinsing and post-baking may be performed.

[0016] In some embodiments, patterning may comprise etching using a hard mask (eg, a metal mask).

[0017] <Etching> In some embodiments, the exposed surface of the hydrophobic film is subjected to an etching process. This results in the hydrophobic film being patterned in accordance with the resist pattern. The etching of the hydrophobic film is not particularly limited, but may be, for example, oxygen etching. This exposes the substrate surface.

[0018] In some embodiments, the exposed substrate surface is coated with a target material, which may be coated over the entire substrate, i.e., on top of the resist, to form a film that includes or consists essentially of the target material.

[0019] <Target Material> Examples of the target material include gold, platinum, aluminum, copper, iron, cobalt, silver, tin, indium, zinc, gallium, chromium, and oxides thereof. The target material may be an oxidizable material. The target material may be chromium (Cr). The target material may be zinc oxide (ZnO).

[0020] <Photoresist Removal> In some embodiments, after application of the target material, the photoresist may be removed. At that time, the target material applied on the surface of the photoresist may be removed together. This process may be called lift-off. During lift-off, the hydrophobic film and the patterned target material may remain on the substrate surface.

[0021] <Target Material Treatment> In some embodiments, the applied target material may be treated. The treatment may be a treatment of the surface of the target material. The treatment may be heating. Heating may include heating the substrate in a furnace, irradiating the target material or substrate with a laser, etc. The treatment may be oxidation of at least the surface, or a portion or all of the volume of the target material. Examples of oxidation include heating in an oxidizing atmosphere, plasma treatment, etc.

[0022] In some embodiments, the target material may be processed or treated. For example, a microstructure may be formed on the surface of the target material. The microstructure may be formed by etching the target material. In some embodiments, the microstructure may be formed on the surface of the target material. For example, a material that forms the microstructure may be grown on the surface of the target material.

[0023] Nanowires In some embodiments, nanowires may be formed on a surface of a target material. For example, nanowire growth particles or catalysts may be applied to the surface of the target material, and nanowires may be grown from the surface. In some embodiments, the target material may be a material that can be a catalyst for nanowire growth or a growth starting point.

[0024] Examples of particles or seed layers for forming nanowires include ZnO and CrO. Nanowires using ZnO can be grown on the surface of these seed materials using a hydrothermal synthesis method. In one example, ZnO is first applied to the surface of the substrate (surface of the target material). Then, zinc nitrate hexahydrate (Zn(NO ３ ) ２ ・6H ２O), hexamethylenetetramine (C ６ H １２ N ４ The substrate is immersed in a precursor solution prepared by dissolving ZnO in deionized water. This allows ZnO nanowires to grow on the surface of the target material. When ZnO is used as the target material, it acts as the nanowire-forming particles. Therefore, there is no need to separately apply ZnO to the surface of the target material.

[0025] Examples of catalysts for producing nanowires include gold, platinum, aluminum, copper, iron, cobalt, silver, tin, indium, zinc, gallium, chromium, and titanium.

[0026] Catalyzed nanowires can be fabricated by the following procedure: (a) depositing a catalyst onto the surface of the target material; (b) SiO ２ , Li ２ O, MgO, Al ２ O ３ , CaO, TiO ２ , Mn ２ O ３ , Fe ２ O ３ , CoO, NiO, CuO, ZnO, Ga ２ O ３ , SrO, In ２ O ３ , SnO ２ , Sm ２ O ３ Nanowires are formed using a material such as EuO by a physical vapor deposition method such as pulsed laser deposition or VLS (Vapor-Liquid-Solid) method. Note that the nanowires produced using the catalyst may be nanowires with no branched chains or nanowires with branched chains.

[0027] In some embodiments, a coating layer may be formed on the surface of the nanowires using a deposition method such as sputtering, electron beam (EB) deposition, physical vapor deposition (PVD), or atomic layer deposition (ALD).

[0028] In some embodiments, the coating layer may be a material with high thermal conductivity. For example, a nanowire device having such a coating layer can be used for heat treatment of a sample. In some embodiments, the coating layer may be a material that has binding affinity with peptides and / or nucleic acids and has high thermal conductivity. This allows the surface of the nanowire to be modified with peptides and / or nucleic acids. The modified nanowire has the ability to efficiently capture biomolecules or separate them from other substances. These are examples, and the materials used for the coating layer are not limited to these.

[0029] Lift-Off In some embodiments, the hydrophobic film may be removed after processing of the target material, such as heating, oxidizing, or forming a microstructure on the target material. The hydrophobic film may be removed by lift-off.

[0030] Hydrophobic films that have undergone heating or oxidation treatment generally become brittle. The hydrophobic film can be peeled off from the substrate by immersing the substrate in water and heating it to a predetermined temperature. In this case, ultrasonic cleaning or the like may be used to accelerate the removal of the hydrophobic film.

[0031] After removing the hydrophobic film, the substrate surface is provided with the target material (or additional microstructures) patterned thereon, and a substrate surface free of the target material. The substrate surface thus exposed and patterned is substantially free of the target material or microstructures. Therefore, the formation of non-specifically processed surfaces or microstructures associated with the target material is suppressed or avoided. Alternatively, the surface retains substantially the flatness or regularity (e.g., particle-free) of the original substrate surface. For example, such a clean substrate surface can be bonded to another substrate or member to form a fluid-tight bonded surface. This allows the fabrication of a fluidic channel or fluidic device with high sealing properties.

[0032]

[0013] Further aspects and advantages of the present disclosure will become readily apparent to those skilled in the art from the following detailed description, wherein only illustrative embodiments of the present disclosure are shown and described. As will be realized, the present disclosure is capable of other and different embodiments, and its several details are capable of modifications in various obvious respects, all without departing from the present disclosure. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive.

[0033] FIG. 1 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 2 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 3 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 4 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 5 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 6 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 7 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment. FIG. 8 shows a cross-sectional view of a substrate to explain a method of patterning a substrate according to an embodiment.

[0034] 1A to 1K, a method for patterning a substrate, a method for forming a microstructure on a substrate, and a method for manufacturing a fluidic device according to one embodiment of the present disclosure will be described. In this embodiment, ZnO nanowires are grown in the patterned region, and a fluidic device having the nanowires is manufactured. This is an example, and the present disclosure should not be construed as being limited to this embodiment.

[0035] As shown in FIG. 1A, a substrate 101 is prepared, and a hydrophobic film 102 is formed on its surface. The substrate 101 is typically a silicon substrate or a glass substrate used in semiconductor processes. The substrate 101 may be cleaned in advance, thereby removing contaminants or particles from the surface. The hydrophobic film 102 can be formed by spin coating. The applied hydrophobic film 102 is then baked. In this example, Cytop (registered trademark, manufactured by AGC Corporation) was used as the hydrophobic film 102.

[0036] 1B, a photoresist 103 is applied to the surface of the hydrophobic film 102. A material used in semiconductor processes can be used for the photoresist 103. In this example, AZ4903 (manufactured by Merck Performance Materials GmbH) was used.

[0037] As shown in FIG. 1C, the photoresist 103 is patterned. The photoresist 103 is pre-baked. It is exposed to light corresponding to the pattern in which the target material will be formed later. It is then developed. For example, NMD-3 (manufactured by TOKYO OHKA KOGYO CO., LTD.) may be used for development. Next, the substrate is rinsed with pure water and dried by nitrogen blowing. Finally, the photoresist 103 is post-baked. As a result, the photoresist 103 is patterned.

[0038] As shown in FIG. 1D, the portions of the hydrophobic film 102 that are opened or exposed in FIG. 1C are etched. Oxygen etching may be performed on the hydrophobic film 102. For example, the etching device may be a device used in general semiconductor processes. In this embodiment, an RF plasma device, TEP-01C2 (manufactured by TATEYAMA MACHINE CO., LTD.), was used. As a result, the hydrophobic film 102 was removed in the portions defined by the openings in the photoresist 103, exposing the surface of the substrate 101.

[0039] 1E, a target material 104 is applied or deposited to cover the entire substrate 101, including the surface of the substrate 101 exposed in FIG. 1D, i.e., the surface of the photoresist 103. In this embodiment, chromium (Cr) is deposited as the target material 104 by sputter deposition to a thickness of more than 100 nm.

[0040] As shown in FIG. 1F, the photoresist 103 and the target material 104 formed on the photoresist 103 are removed by lift-off. In this embodiment, the entire substrate 101 is immersed in heated 2-propanol for a predetermined time. Then, ultrasonic cleaning is performed. As a result, the target material 104 (chromium) is patterned on the substrate 101, and the remaining surface of the substrate 101 is covered with the hydrophobic film 102.

[0041] As shown in FIG. 1G, the target material 104 is annealed. In this embodiment, the chromium of the target material 104 is oxidized by being held at 400° C. in an air atmosphere. The air atmosphere contains a sufficient amount of oxygen to oxidize the chromium. The atmosphere during heating may be an oxidizing atmosphere. Alternatively, the surface of the chromium may be oxidized by plasma treatment.

[0042] As shown in FIG. 1H, ZnO nanowires 105 were grown as a microstructure on the surface of the oxidized target material 104 (chromium). In this embodiment, the ZnO nanowires 105 were grown using a hydrothermal synthesis method. If the hydrophobic film 102 did not cover the surface of the substrate 101, the nanowires 105 would likely grow non-specifically on the surface of the substrate 101. However, as shown in FIG. 1H, because the hydrophobic film 102 covers the surface of the substrate 101, the nanowires 105 can only grow on the surface of the patterned target material 104.

[0043] Next, the hydrophobic film 102 is removed or lifted off. As a result, as shown in FIG. 1I, the substrate 101 has microstructures 105 (nanowires) formed on its surface at the positions of the target material 104 defined by patterning. The microstructures 105 (nanowires) are substantially absent on the surface of the substrate 101 where the target material 104 is not present. In this way, the target material can be used as a seed layer or starting point to form the microstructures only in those portions.

[0044] In this embodiment, a fluidic device 100 incorporating the microstructure 105 formed in this manner was manufactured. As shown in FIG. 1J, the fluidic device 100 mainly comprises a substrate 101 and a cover (substrate) 111 bonded thereto. This substrate 101 is the substrate 101 also shown in FIG. 1I. The cover 111 has a frame 112 and an internal space 120 surrounded by the frame 112, so as to cover the target material 104 and the microstructure 105 of the substrate 101. The cover 111 is in close contact with the exposed surface of the substrate 101 where the microstructure 105 is not present, via the frame 112, forming a bonding interface 130. The bonding interface 130 has high fluid-tightness. This is because the surface of the substrate 101 forming the bonding interface 130 is free of non-specific growth such as the microstructure 105 and has a flat surface similar to the original surface.

[0045] 1J includes a substrate 101 having a target material 104 and a microstructure 105 on its surface, and a cover 111 that is in close contact with the substrate 101 to enclose the microstructure 105. Alternatively, the substrate 101 and the cover 111 are in close contact with each other at a bonding interface 130 to form an internal space or flow channel 120 that encloses the microstructure 105 therein.

[0046] In some embodiments, as shown in FIG. 1J , the flow channel 120 may have multiple target material pattern portions 104 and / or microstructures 105. In some embodiments, each flow channel may have a single target material pattern portion 104 and / or microstructure. In some embodiments, a single target material pattern portion 104 and / or microstructure may be formed on the surface of the substrate. A cover having a single interior space may be bonded to the substrate.

[0047] In some embodiments, the surface of the substrate may have a plurality of target material pattern portions and / or microstructures. The fluidic device 200 shown in FIG. 2 includes a substrate 201 having a surface with a plurality of microstructures 204 and nanowires 205 formed thereon, and a cover 211 tightly adhered to the substrate 201. The cover 211 has a plurality of flow channels or internal spaces 220-1, 220-2, and 220-3, and is adhered to the substrate 201 at a bonding surface surrounding the spaces to form a bonding surface 230. The flow channels 220-1, 220-2, and 220-3 are formed to contain the corresponding microstructures 204 and nanowires 205, respectively. Thus, the fluidic device 200 shown in FIG. 2 has a plurality of flow channels 220-1, 220-2, and 220-3.

[0048] In some embodiments, the fluidic device 200 may be cut along the boundaries 240-1, 240-2 of the flow channels 220-1, 220-2, 220-3, resulting in multiple individual fluidic devices 200-1, 200-2, 200-3. In some embodiments, the cutting may include a blade or laser dicing process.

[0049] In some embodiments, after cutting the substrate 201, a cover may be sealed to each individual substrate to produce an individual fluidic device (not shown).

[0050] 2 illustrates the formation or manufacture of three individual flow channels 220-1, 220-2, and 220-3 and three individual fluidic devices 200-1, 200-2, and 200-3, but the present disclosure is not limited thereto. For example, a plurality of flow channels and / or fluidic devices may be manufactured from a single substrate. The number of such channels and / or fluidic devices may be other than three.

[0051] In some embodiments, the cover may have multiple internal spaces and multiple frames surrounding each of the internal spaces (not shown). The cover having the multiple internal spaces may be brought into close contact with multiple target material patterns and / or microstructures, and the bonded substrate and cover may be cut or separated according to each internal space.

[0052] As used in this disclosure, a "flow path" generally refers to a space that contains a fluid. The term flow path may also be used interchangeably with terms such as fluid chamber, fluid container, etc. A flow path may have an inlet for introducing a fluid thereto and / or an outlet for discharging a fluid therefrom. A fluid may flow within the flow path or may be introduced into the flow path and then substantially halt.

[0053] In some embodiments, the flow path may include a so-called chaotic mixer or other structure that induces nonlinear and / or three-dimensional flow in the fluid flowing through the flow path. Such a structure may include, for example, a step in the flow path, a change in cross-sectional area, a change in flow path direction, etc.

[0054] A chaotic mixer having herringbone-shaped irregularities may be arranged on the inner wall surface of the channel (the surface of the substrate or the surface of the cover). This can promote nonlinear fluid flow. For example, this can guide a larger amount of the target substance in the solution to microstructures (e.g., nanowires) arranged on multiple inner wall surfaces or on the curved inner wall surface.

[0055] The fluidic device may detect, measure, analyze, modify, process, and / or capture substances contained in a fluid introduced into a flow path. The fluidic device may include nanowires. The fluidic device may use the nanowires to capture substances contained in the fluid. For example, the fluidic device may capture biomolecules in a bodily fluid with nanowires disposed in the flow path.

[0056] In the present disclosure, the fluid introduced into the flow path may be a bodily fluid. "Body fluid" refers to a body fluid obtained from a subject or a sample derived from such a body fluid. The body fluid may be, but is not limited to, blood, serum, plasma, lymph, tissue fluid such as interstitial fluid or intercellular fluid, body cavity fluid, serous cavity fluid, pleural fluid, peritoneal fluid, pericardial fluid, cerebrospinal fluid, synovial fluid, or aqueous humor. The body fluid may be a digestive fluid such as saliva, gastric juice, bile, pancreatic juice, or intestinal fluid, or may be sweat, tears, nasal mucus, urine, semen, vaginal fluid, amniotic fluid, or milk. The body fluid may be an animal body fluid or a human body fluid.

[0057] The biomolecule may be an organelle or a vesicle. The vesicle may be, but is not limited to, a vacuole, a lysosome, a transport vesicle, a secretory vesicle, a gas vesicle, an extracellular matrix vesicle, an extracellular vesicle, or the like, or may include a plurality thereof. The extracellular vesicle may be, but is not limited to, an exosome, an exotome, a shedding microvesicle, a microvesicle, a membrane particle, a plasma membrane, an apoptotic vesicle, or the like. The vesicle may contain nucleic acid.

[0058] The biomolecule may be or include, but is not limited to, a cell. The cell may be a red blood cell, a white blood cell, an immune cell, etc. The biomolecule may be a virus, a bacterium, etc.

[0059] The solution may be a body fluid or a body fluid-derived liquid (dilution solution, treatment solution, etc.). The solution may be a non-body fluid (non-body fluid-derived) solution, an artificially prepared liquid, or a mixture of a body fluid or a body fluid-derived solution and a non-body fluid-derived solution. The solution may be a solution used for sample measurement or a solution used for calibration measurement. For example, the solution may be a standard solution or a calibration solution. The sample to be measured may be a specimen. The solution may contain a physiological buffer solution, such as phosphate-buffered saline (PBS) or N-tris(hydroxymethyl)methyl-2-aminoethanesulfonic acid buffer (TES), containing the substance to be recovered.

[0060] The present disclosure also provides the following embodiments: A001 A method for patterning a target material on a substrate, comprising: providing a substrate; forming a hydrophobic film on a surface of the substrate; patterning the hydrophobic film to expose a portion of the surface of the substrate; applying an oxidizable target material to the portion of the surface of the substrate exposed by the patterning; and heating the substrate having the oxidizable target material and the hydrophobic film or oxidizing the target material on the substrate. A001b A method for patterning a target material on a substrate, comprising: providing a substrate; forming a hydrophobic film on a surface of the substrate; patterning the hydrophobic film to expose a portion of the surface of the substrate; applying a target material to the portion of the surface of the substrate exposed by the patterning; and performing a surface treatment on the substrate having the target material and the hydrophobic film. A011 The method of embodiment A001 or any embodiment, further comprising removing the hydrophobic film after heating the substrate or oxidizing the target material. A012 The method of embodiment A011 or any embodiment, wherein removing the hydrophobic film comprises forming a pattern of the target material on the surface of the substrate. A013 The method of embodiment A011 or A012 or any embodiment, wherein removing the hydrophobic film comprises exposing portions of the surface of the substrate that are not coated with the target material. A015 The method of any one of embodiments A001 to A013 or any embodiment, wherein the hydrophobic film is formed of a fluorine compound.A016 The method according to embodiment A015 or any embodiment, wherein removing the hydrophobic film comprises removing the heated or oxidized fluorine compound using ultrasonic cleaning. A021 The method according to embodiment A0012, or any one of A013 to A016 reciting embodiment A012, or any one of embodiments, further comprising forming a channel on the substrate so as to contain the patterned target material therein. A022 The method according to embodiment A021 or any one of embodiments, wherein forming the channel on the substrate comprises closely contacting a channel member, on which at least a portion of the channel is formed, to the surface of the substrate. A023 The method according to embodiment A022 or any one of embodiments, wherein the channel member defining the channel and the surface of the substrate are in close contact with each other. A031 The method according to any one of embodiments A001 to A033, or any one of embodiments, wherein the substrate has a semiconductor, glass, metal, or polymer on at least its surface. A041 The method of any one of embodiments A011 to A031 or any embodiment, further comprising treating the surface of the target material before removing the hydrophobic film. A042 The method of any one of embodiments A011 to A031 or any embodiment, further comprising forming a microstructure on the surface of the target material before removing the hydrophobic film. A043 The method of embodiment A042 or any embodiment, wherein the microstructure is a nanowire. A044 The method of embodiment A042 or A043 or any embodiment, wherein the microstructure has the ability to capture biomolecules. A051 The method of any one of embodiments A001 to A044 or any embodiment, wherein the target material is a metal. A052 The method of embodiment A051 or any embodiment, wherein the target material is chromium.A053 The method of embodiment A043 or any embodiment, wherein the target material is chromium, and forming a microstructure on the surface of the target material comprises forming nanowires comprising ZnO on the oxidized chromium surface. A061 The method of any one of embodiments A001 to A053 or any embodiment, wherein patterning the hydrophobic film to expose a portion of the surface of the substrate comprises applying a photomask on the hydrophobic film and patterning the photomask, and applying an oxidizable target material to the portion of the surface of the substrate exposed by the patterning comprises applying the target material on the applied, patterned photomask and removing the photomask and the target material. A062 The method of embodiment A061 or any embodiment, wherein removing the photomask and the target material comprises removing the photomask and the target material by lift-off.

[0061] While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. It is not intended that the present invention be limited by the specific examples provided within the specification. While the present invention has been described with reference to the foregoing specification, the descriptions and illustrations of the embodiments herein are not meant to be construed in a limiting sense. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the invention. Furthermore, it should be understood that all aspects of the present invention are not limited to the specific depictions, configurations, or relative proportions set forth herein, which depend upon a variety of conditions and variables. It should be understood that various alternatives to the embodiments of the present invention described herein may be used in practicing the invention. It is therefore intended that the present invention cover all such alternatives, modifications, variations, or equivalents. It is intended that the following claims define the scope of the invention, and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

1. A method for patterning a target material on a substrate, comprising: providing a substrate; forming a hydrophobic film on the surface of the substrate; patterning the hydrophobic film to expose a part of the surface of the substrate; applying a target material to the part of the surface of the substrate exposed by the patterning so that the hydrophobic film is exposed on other parts of the surface of the substrate; oxidizing the target material on the substrate; forming a fine structure on the surface of the target material before removing the hydrophobic film; and removing the hydrophobic film after forming the fine structure. A method comprising the above steps.

2. The method according to claim 1, wherein removing the hydrophobic film comprises exposing a part of the surface of the substrate where the target material is not applied. A method.

3. The method according to claim 1, wherein the hydrophobic film is formed of a fluorine compound. A method.

4. The method according to claim 1, further comprising forming a flow path on the substrate so as to internally contain the target material and the fine structure. A method.

5. The method according to claim 4, wherein forming the flow path on the substrate comprises bringing a flow path member having at least a part of the flow path formed thereon into contact with the surface of the substrate. A method.

6. The method according to claim 1, wherein the substrate has at least on its surface a semiconductor, glass, metal, or polymer. A method.

7. The method according to claim 1, wherein the fine structure is a nanowire. A method.

8. The method according to claim 1 or 7, wherein the fine structure has the ability to capture biomolecules. A method.

9. The method according to claim 1, wherein the target material is chromium. A method.

10. The method according to claim 1, wherein the target material is chromium, and forming a fine structure on the surface of the target material comprises forming nanowires containing ZnO on the oxidized chromium surface. A method.

11. The method according to claim 1, wherein patterning the hydrophobic film to expose a part of the surface of the substrate comprises applying a photomask on the hydrophobic film and patterning the photomask. Applying an oxidizable target material to the part of the surface of the substrate exposed from the patterning includes applying the target material onto the applied and patterned photomask and removing the photomask and the target material. Method. **Claim 12** The method according to claim 11, wherein removing the photomask and the target material is removing the photomask and the target material by lift-off. Method.