Conductive member and method for manufacturing the same

Abstract

To provide a conductive member having an insulating film pattern in which there is no protrusion at the edge of an insulating film and the edge can be used as a region for forming an electric circuit.SOLUTION: The conductive member of the present invention has a pattern of an insulating film on the surface of a conductive substrate. Since the insulating film is a calcined film of a smectite clay mineral, and the pattern of the insulating film has a difference of 1.0 μm or less between the maximum peak height of the edge portion and the height at a position 0.2 mm inside the measurement position of the maximum peak height, it is possible to provide a conductive member having an insulating film pattern in which there is no protruding portion at the edge portion of the insulating film and the edge portion can also be used as the formation region of an electric circuit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a conductive member and a method for manufacturing the conductive member, and more particularly to a conductive member in which an insulating film pattern is formed on the surface of a conductive base material, and a method for manufacturing the conductive member. [Background technology]

[0002] To fabricate an electronic device on a conductive substrate such as steel, it is necessary to prevent short circuits between the electronic device and the conductive substrate, and an insulating film is formed on the surface of the conductive substrate.

[0003] Resin insulating films have been known as insulating films that can be applied by a wet process and are easy to form. However, insulating films formed from resins generally have low heat resistance due to the physical properties of the resin that forms the insulating film, which limits the electronic devices that can be formed on the insulating film and the manufacturing methods thereof.

[0004] In Patent Document 1, the present inventors disclosed that an insulating film formed by applying and baking an insulating film coating liquid in which smectite clay mineral is dispersed using a viscosity reducer not only has excellent insulating properties but also smoothly levels out fine irregularities on the surface of a conductive substrate, thereby enabling the formation of a good electrical circuit. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2018-037605 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when a pattern of the insulating film is formed using a masking film or the like, the coating of the insulating film coating liquid turns up at the edges of the pattern when the masking film is peeled off, and this shape is reflected in the insulating film after firing, forming protrusions at the edges of the pattern. As a result, it is not possible to form electrical circuits at these edges, which reduces the density of the electrical circuits that can be formed on the insulating film, and it is particularly difficult to form electrical circuits on an insulating film with a fine pattern.

[0007] The present invention has been made in consideration of the problems associated with the conventional technology, and its object is to provide a conductive member having an insulating film pattern in which there are no protrusions at the edges of the insulating film and the edges can also be used as areas for forming electrical circuits, and a method for manufacturing the same. [Means for solving the problem]

[0008] As a result of extensive research into achieving the above-mentioned object, the present inventors have found that by pre-baking a coating film of an insulating film coating liquid formed on a resist pattern, then removing the resist and collapsing the pre-baked film on the resist, curling at the edge of the pattern can be prevented, thereby achieving the above-mentioned object, and have completed the present invention.

[0009] That is, the above problems are solved by the conductive member of the present invention described below in (1) or (2). (1) A conductive member having an insulating film pattern on the surface of a conductive substrate, the insulating film is a fired film of a smectite clay mineral, A conductive member characterized in that the difference between the maximum peak height of the insulating film pattern at its edge and the height at a position 0.2 mm inward from the measurement position of the maximum peak height is 1.0 μm or less. (2) The conductive member according to (1) above, further comprising an electric circuit on the insulating film.

[0010] The above problems are also solved by the following method (3) or (4) for producing a conductive member of the present invention. (3) A method for producing a conductive member having an insulating film pattern on a surface of a conductive substrate, comprising: a step of applying an insulating film coating liquid containing a smectite clay mineral and a viscosity reducing agent onto a conductive substrate having a resist pattern formed on its surface; a step of pre-baking the coating film of the insulating film coating liquid; removing the resist by a wet method; a step of subjecting the pre-baked coating film remaining on the surface of the conductive substrate to main baking; Equipped with The temperature of the pre-baking step is 115°C to 145°C, A method for producing a conductive member, wherein the resist removal step uses an organic solvent having a solubility parameter of 9.1 to 14.5. (4) The method for producing a conductive member according to (3) above, further comprising the step of scratching the area where the pre-baked coating film of the insulating film coating liquid is to be removed after the pre-baking step and before the resist removal step. [Effects of the Invention]

[0011] According to the present invention, a coating film of an insulating film coating liquid formed on a resist pattern is pre-baked, and then the resist is removed and the pre-baked film on the resist is collapsed. Therefore, it is possible to provide a conductive member having an insulating film pattern, which allows an electrical circuit to be formed even on the edge of the insulating film, and a method for manufacturing the same. [Brief explanation of the drawings]

[0012] [Figure 1] 1A to 1C are diagrams illustrating steps in a method for manufacturing a conductive member according to the present invention. [Figure 2] 1A to 1C are diagrams illustrating a process of forming a resist pattern on the surface of a conductive substrate. [Figure 3] 10A and 10B are diagrams illustrating a method for measuring the height of protrusions at the edge of an insulating film pattern. [Figure 4] 1 shows roughness curves of Example 2 and Comparative Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0013] <Conductive materials> The conductive member of the present invention will now be described in detail. The conductive member has an insulating film pattern on the surface of a conductive substrate such as a metal. That is, the entire surface of the conductive substrate is not covered with the insulating film, but at least a portion of the conductive substrate is exposed from the insulating film.

[0014] The insulating film is a fired film containing smectite clay mineral as a main component, and has a structure in which plate-like particles of the smectite clay mineral are aligned, adhere to each other, and laminated.

[0015] Such insulating films are almost free of organic matter and therefore have high heat and chemical resistance. Therefore, a metal thin film can be formed on the insulating film by a dry coating method such as vapor deposition or sputtering, and the metal thin film can be corroded and shaped into a grid or rosette shape using an etching solution to form an electrical circuit.

[0016] The insulating film pattern has a difference (height of the protruding part) of 1.0 μm or less between the maximum peak height (height of the most protruding part) at its edge and the height (film thickness) at a position 0.2 mm inward from the measurement position of the maximum peak height, and the entire pattern is smooth, so that breakage and peeling of the electrical circuit can be prevented not only at the center of the pattern but also at its edge.

[0017] Therefore, even if the insulating film has a fine pattern, it is possible to form an electric circuit on the insulating film.

[0018] The insulating film preferably has a maximum height roughness (Rz) of 1.0 μm or less, more preferably 0.5 μm or less. This allows for the formation of a good electrical circuit without breakage or peeling. For the same reason, the height of the protrusions is also preferably 1.0 μm or less.

[0019] The insulating film has high insulating properties because the plate-like particles of the smectite clay mineral are in close contact with each other. The resistance value of the insulating film is 1.00×10 7 It is preferable that the resistance is 1.00×10 Ω or more. 7 By ensuring that the resistance is Ω or more, a short circuit with the conductive substrate can be prevented, and an electric circuit can be formed.

[0020] The insulating film preferably has a thickness of 0.7 μm or more and 20 μm or less. A thickness of 0.7 μm or more allows for the formation of a highly insulating insulating film without coating defects, while a thickness of 20 μm or less allows for the formation of strain sensor devices by preventing cracking of the insulating film as it follows the deformation of the conductive substrate.

[0021] The insulating film preferably has a solid solution layer containing constituent elements of the conductive substrate and constituent elements of the smectite clay mineral on the conductive substrate side. The solid solution layer is formed by the diffusion of the constituent elements of the conductive substrate from the conductive substrate side to the clay layer side. The presence of such a solid solution layer improves peel resistance.

[0022] The structure of the insulating film can be confirmed by observing the cross section of the conductive member using TEM-EDS. The concentration of the constituent elements of the conductive base material in the solid solution layer can be confirmed by drilling the surface of the insulating film with an argon laser and performing elemental analysis using XPS or the like.

[0023] <Method for manufacturing conductive member> Next, a method for producing the conductive member of the present invention will be described. The above manufacturing method is a method for manufacturing a conductive member having an insulating film pattern formed on the surface of a conductive substrate, and as shown in FIG. 1, includes the steps of applying an insulating film coating liquid containing a smectite clay mineral and a viscosity reducer onto a conductive substrate having a resist pattern formed on its surface, pre-firing the coating film of the insulating film coating liquid, removing the resist by a wet method, and firing the pre-firing coating film remaining on the surface of the conductive substrate.

[0024] This method of manufacturing conductive materials involves forming an insulating film pattern by applying the lift-off method commonly used in semiconductor manufacturing. An insulating film coating liquid is applied onto a pattern formed with resist, and the resist is then removed, leaving the insulating film pattern only in areas where there was no resist. This allows the resist pattern to be transferred to the insulating film.

[0025] However, since the insulating film is formed by a wet coating method in which an insulating film coating liquid is applied, rather than by a dry coating method such as a vapor deposition method or a sputtering method, the lift-off method used in semiconductor manufacturing cannot be applied as is.

[0026] In other words, in the dry coating method, atoms and molecules such as metals that form the metal film are supplied from the out-of-plane direction of the substrate, so by adding eaves-like protrusions to the top of the resist or by making the resist shaped like an inverted taper, it is possible to prevent the side walls of the resist from being covered with the metal film, and it is possible to remove the resist by allowing the resist removal liquid to penetrate from the side walls.

[0027] In contrast, in the wet coating method for forming the insulating film, the insulating film coating liquid flows in the in-plane direction of the conductive substrate and coats the resist pattern, so the entire resist is covered with the insulating film coating liquid, making it impossible to remove the resist.

[0028] In the present invention, before the coating film of the insulating film coating liquid is completely baked to form a baked film having excellent chemical resistance, the coating film of the insulating film coating liquid is pre-baked to form a pre-baked coating film of the insulating film coating liquid that is permeable to the resist removing liquid but is not destroyed by the resist removing liquid, and the resist removing liquid is allowed to permeate through this pre-baked coating film to the resist.

[0029] As a result, even if the entire resist is covered with the pre-baked coating film, the resist removal liquid can penetrate through the pre-baked coating film to the resist and dissolve and remove the resist, so that the resist pattern can be transferred to the pre-baked coating film.

[0030] At this time, the pre-baked coating film on the resist loses its base and collapses as the resist is removed, and the resist pattern is transferred to the pre-baked coating film, so it is not lifted up and peeled off from the conductive substrate as when a masking film is peeled off.

[0031] Therefore, the insulating film obtained by firing the above-mentioned pre-fired coating film maintains the smooth, flat state of the insulating film coating liquid even at the edge of the pattern, just as it was when it was applied, and therefore it is possible to form an electric circuit on the insulating film using a dry coating method such as vapor deposition or sputtering.

[0032] The method for applying the insulating film coating liquid may be any method capable of forming a smooth coating film of the insulating film coating liquid, and examples thereof include spin coating, gap coater coating, dip coating, bead coating, and ring coating. Among these, spin coating is preferred because it has excellent embedding properties and can flatten steps on the surface of the conductive substrate.

[0033] The pre-baking temperature in the step of pre-baking the coating film of the insulating film coating fluid is preferably 115°C to 145°C.

[0034] The pre-baked coating film obtained by pre-baking within the above temperature range is not affected by the resist removal solution in the resist removal step using a wet method described below, and its surface shape and properties are not changed by the resist removal solution, and further, it is firmly fixed to the conductive substrate in the resist-free areas.

[0035] That is, if the pre-baking temperature is less than 115°C, the bonding strength between the plate-like particles of the smectite clay mineral and between the particles and the conductive substrate will be weak, and there is a risk that the pre-baked coating film will be washed away by the resist removal solution. On the other hand, if the temperature exceeds 145°C, the resist removal solution will have difficulty penetrating, and it may become impossible to remove the resist.

[0036] The pre-baking time is preferably 30 minutes to 2 hours, although it depends on the thickness of the coating of the insulating film coating liquid.

[0037] The step of removing the resist by a wet method is a step of allowing a resist removal liquid to penetrate into the resist through the pre-baked coating film, removing the pre-baked coating film on the resist together with the resist, and forming a pattern of the pre-baked coating film on the surface of the conductive substrate.

[0038] The method of permeating the resist removing liquid may include immersing the conductive substrate on which the pre-baked coating film is formed in the resist removing liquid.

[0039] As the resist remover, a solvent can be used that does not affect the surface shape or properties of the pre-baked coating film and can penetrate into the pre-baked coating film to dissolve the resist.

[0040] The resist removal liquid is preferably an organic solvent having a solubility parameter of 9.1 to 14.5, and more preferably an organic solvent having a solubility parameter of 9.1 to 12.7.

[0041] Smectite clay minerals have cations such as sodium (Na) between their layers and are hydrophilic. Therefore, even if an organic solvent is capable of dissolving resist, if the solubility parameter is less than 9.1, the permeability of the smectite clay mineral into the pre-baked coating film is low, making it difficult to dissolve the resist covered with the pre-baked coating film.

[0042] Furthermore, if the solubility parameter exceeds 14.5, the smectite clay mineral has a high affinity with the pre-baked coating film, causing the pre-baked coating film to swell through penetration, making the surface of the pre-baked coating film prone to becoming rough.

[0043] Examples of organic solvents with parameters of 9.1 to 14.5 include acetone (SP value: 9.9), methyl ethyl ketone (SP value: 9.3), methyl acetate (SP value: 9.6), ethyl acetate (SP value: 9.1), ethyl alcohol (SP value: 12.7), and methyl alcohol (SP value: 14.5).

[0044] The method for producing a conductive member of the present invention can, if necessary, include a step of mechanically creating grooves or cracks in the area where the pre-baked coating film is to be removed, after the pre-baking step and before the resist removal step, to facilitate penetration of the resist removal liquid.

[0045] By scratching the pre-baked coating film, the resist remover can penetrate more easily, and the resist can be dissolved more quickly.

[0046] The scratches can be made by ion milling, cutting, or by scratching with a pick tool.

[0047] The main firing step is a step of firing the pre-fired coating film to form an insulating film, and is performed in a firing furnace or oven at 450°C to 675°C for 10 minutes to 10 hours, thereby forming an insulating film pattern on the surface of the conductive substrate.

[0048] The conductive substrate is not particularly limited, and examples thereof include stainless steel, iron, copper, titanium, etc. When used as a metal component for a robot strain sensor, precipitation-hardened stainless steel is preferably used because it has high substrate strength and is excellent in high-speed response to external forces.

[0049] As the resist for forming a pattern on the surface of the conductive substrate, a resist that can be dissolved and removed by exposure to light can be used, such as AZP4330, AZP4620 (both manufactured by Merck Performance Materials LLC), FPPR-P60ET (manufactured by Fuji Pharmaceutical Co., Ltd.), etc.

[0050] The insulating film coating liquid contains a smectite clay mineral, a viscosity reducer, and a dispersion medium.

[0051] The smectite clay minerals are minerals with a layered structure in which plate-like primary particles with a thickness of about 1 nm are piled up.

[0052] Examples of smectite clay minerals include saponite, hectorite, sauconite, stevensite, swinholdite, montmorillonite, beidellite, nontronite, and volconstite, but synthetic hectorite with a controlled primary particle size is preferred.

[0053] The viscosity reducer prevents the plate-like particles of the smectite clay mineral from forming a house-of-cards structure and forming a highly viscous gel, thereby enabling the application and deposition of the insulating film coating solution.

[0054] Examples of the viscosity reducing agent include alkali metal etidronate and ammonium etidronate. The amount of the viscosity reducing agent added is preferably 0.15 to 0.40 mmol per 1 g of the smectite clay mineral.

[0055] The dispersion medium improves the affinity between the insulating film coating liquid and the surface of the conductive substrate, prevents repelling and uneven coating, and improves the drying properties of the insulating film coating liquid.

[0056] Examples of the dispersion medium that can be used include water-soluble organic solvents such as alcohol-based solvents such as methyl alcohol, ethyl alcohol, isopropanol, butanol, and 3-methoxy-3-methyl-1-butanol; acetate-based solvents such as methyl acetate, ethyl acetate, and 3-methoxy-3-methyl-1-butyl acetate; glycol ether-based solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, and propylene glycol monomethyl ether; and ketone-based solvents such as acetone and methyl ethyl ketone. These may be used alone or in combination of two or more. Among these, glycol ether solvents are preferred because they have a high flash point, are safe, and have a viscosity-reducing effect, and ethylene glycol monobutyl ether is particularly preferred. [Example]

[0057] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0058] First, an experiment was carried out to determine the conditions under which an insulating film pattern can be formed by the lift-off method.

[0059] [Experimental Example] (Preparation of insulating film coating liquid) While stirring the ion-exchanged water at 1000 rpm using a disper, 0.22 mmol of sodium etidronate was added to 1 g of clay mineral and dissolved, and then 19 parts by mass of synthetic hectorite (Laponite RD, manufactured by BYK Additives & Instruments; primary particle diameter (median diameter) 60 nm) was added in small amounts to uniformly disperse the clay mineral.

[0060] Next, a mixed solution of 0.1 parts by mass of a nonionic surfactant (polyoxyethylene lauryl ether: DKS NL-40 manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 4.0 parts by mass of ethylene glycol monobutyl ether, and 1.5 parts by mass of ethanol was added and homogenized, after which ultrasonic treatment was performed for 20 seconds per 100 g, and further filtered through a 10 μm membrane filter to obtain an insulating film coating solution with a clay solids content of 19% by mass.

[0061] (Production of conductive materials) After thorough washing with acetone, a resist (AZP4330) was uniformly applied by spin coating to the surface of a conductive substrate (SUS304) that had been hydrophilized by atmospheric plasma treatment, as shown in Figure 2. The resist was then exposed to ultraviolet light through a patterned mask, and the areas exposed to the ultraviolet light were dissolved and removed using a developer (AZ400K Developer, manufactured by AZ Electronic Materials), forming a resist pattern on the surface of the conductive substrate.

[0062] (Coating of insulating film coating liquid) The insulating film coating liquid was spin-coated (1000 rpm, 20 seconds) onto the surface of the conductive substrate on which the resist pattern was formed, and then left to dry at room temperature for 1 hour to form a coating film of the insulating film coating liquid with a thickness of approximately 6 μm.

[0063] (Pre-baking) The conductive substrate on which the coating film of the insulating film coating liquid had been formed was pre-baked for 1 hour at the temperature shown in Table 1 below to form a pre-baked coating film.

[0064] (Removal of resist) The conductive substrate on which the above pre-baked coating film was formed was immersed in an organic solvent shown in Table 1 below to remove the resist, and a pattern of the pre-baked coating film was formed on the surface of the conductive substrate.

[0065] (Final firing) The conductive substrate on which the pattern of the pre-baked coating film was formed was baked at 600° C. for 2 hours to obtain a conductive member.

[0066] <Evaluation> The prepared conductive members were evaluated by the following methods and criteria. The evaluation results are shown in Table 1.

[0067] (Appearance of pre-baked coating film after resist removal) ◯: The pattern of the pre-baked coating film can be formed exactly as the resist pattern, and there is no discoloration. △: The pattern of the pre-baked coating film was formed almost exactly as the resist pattern, with some discoloration observed. ×: The resist pattern was not transferred to the pre-baked coating film.

[0068] (Surface roughness of pre-baked coating film after resist removal) ◎: Smooth (maximum height roughness (Rz) 0.5 μm or less). ◯: Almost smooth (maximum roughness height (Rz) 1.0 μm or less). △: Rough (maximum roughness in height (Rz) exceeds 1.0 μm). ×: Resist remains on the pre-baked coating film.

[0069] (Appearance of insulating film) Good: The insulating film pattern can be formed exactly as the resist pattern, and there is no discoloration. △: The insulating film pattern was formed exactly as the resist pattern, but some discoloration was observed. ×: The resist pattern could not be completely transferred onto the insulating film.

[0070] [Table 1]

[0071] The results in Table 1 show that if the pre-baking temperature is 115°C to 145°C, the resist remover can penetrate the pre-baked coating film and remove the resist.

[0072] In Experimental Example 9, because the pre-baking temperature was low, the resist remover caused the pre-baked coating film to collapse in the areas that should have remained, and the resist pattern could not be completely transferred.

[0073] Furthermore, the surface of the pre-baked coating film after resist removal is smooth and no discoloration is observed in the insulating film, indicating that even if organic solvents with a solubility parameter of 9.1 to 14.5 penetrate into the pre-baked coating film, they do not affect the properties of the pre-baked coating film and a good insulating film can be obtained.

[0074] In Experimental Example 6, the pre-baked coating film was swelled by the resist remover, and the smoothness was slightly reduced compared to Experimental Examples 1 to 5.

[0075] [Comparative Example] Instead of the conductive substrate on which a resist pattern was formed, the insulating film coating liquid was applied to the surface of the conductive substrate on which a pattern was formed using a masking film, and then the masking film was peeled off to form three independent patterns of the insulating film coating liquid coating film on the surface of the conductive substrate. Further, after drying at 115° C. for 1 hour, the substrate was baked at 600° C. for 2 hours in the same manner as in the experimental example, and a conductive member having an insulating film pattern at three locations was obtained.

[0076] [Example] The conductive members produced in the above experimental examples 1 to 4 were designated as the conductive members of Examples 1 to 4, respectively, and the three patterns formed on the conductive member of the comparative example were designated as comparative examples 1 to 3, and the protrusion heights of their edges were measured using the following method.

[0077] Using a surface roughness measuring instrument (Mitutoyo Corporation: SJ-210), the probe was moved along the bold line shown in Figure 3 from the exposed part of the conductive substrate toward the insulating film pattern, as shown in Figure 3, and the roughness curve from the conductive substrate to the insulating film was measured based on JIS B 0601-1982.

[0078] Specifically, as described above, measurement is started from the conductive substrate, and the point of the insulating film where it begins to rise from the baseline of the conductive substrate is taken as the starting point of the edge (baseline: reference 0). The height from the baseline of the highest protrusion within a range of 0.2 mm in the X-axis direction from the starting point of the edge is measured as the maximum peak height of the edge (Y-axis). The height of the insulating film (Y-axis: insulating film thickness) was measured at a position (X-axis) 0.2 mm inward from the position (X-axis) where the maximum peak was measured, and the difference (thickness difference = height of the highest protrusion) between the maximum peak height (Y-axis) and the height of the insulating film (Y-axis) 0.2 mm inward from the peak position of the highest protrusion was calculated. The definitions of the maximum peak height, film thickness, and height of the highest protrusion at the edge are shown in Figure 3, the measurement results are shown in Table 2, and the roughness curves of Example 2 and Comparative Example 3 are shown in Figure 4.

[0079] Furthermore, a Cr-N thin film having a thickness of about 500 nm was formed on the insulating film of the conductive member of each of the examples and comparative examples by reactive sputtering, which involves introducing a small amount of nitrogen gas together with argon gas. The sputtering conditions were as follows: a Cr disk with a nominal purity of 99.9% was used as the target; the vacuum degree before film formation (background vacuum degree), the target-substrate distance (TS distance), the film formation gas pressure, and the input power were each set at 2 × 10 -5 The nitrogen addition amount added to the chromium was controlled to 0.03% by adjusting the nitrogen gas flow rate ratio (N2 / (Ar+N2)) introduced.

[0080] Next, photolithography and etching using a Cr etching solution were used to form a lattice-shaped sensing area with eight folds, a line width and spacing of 0.05 mm, and a length of 2 mm, and this was then heat-treated in air at 200°C for 30 minutes.

[0081] Then, a Ni thin film electrode for measuring resistance was formed on the Cr-N thin film by lift-off method, and a Cr-N strain sensor was obtained. The electrical circuit formation status is shown in Table 2.

[0082] [Table 2]

[0083] The results in Table 2 show that the insulating film of the conductive member of the example is almost flat from the edge to the center, whereas the insulating film of the conductive member of the comparative example has protrusions formed on the edge and the heights of these protrusions vary, resulting in poor pattern transferability.

[0084] The Cr-N strain sensor using the conductive member of the example exhibited a high gauge factor, which confirmed that the insulating film did not experience a decrease in insulation resistance due to the resist remover, and that the electrical circuit did not peel off or break. [Explanation of symbols]

[0085] 1 Conductive base material 2. Resist 2a Deteriorated resist 3. Insulating film coating liquid 4 Pre-baked film 5. Insulating film 6 Electrical Circuits 7. Mask

Claims

1. A conductive member having an insulating film pattern on a surface of a conductive substrate, the insulating film is a fired film of a smectite clay mineral, A conductive member characterized in that the difference between the maximum peak height of the edge of the insulating film pattern and the height at a position 0.2 mm inward from the measurement position of the maximum peak height is 1.0 μm or less.

2. 2. The conductive member according to claim 1, further comprising an electric circuit on the insulating film.

3. A method for producing a conductive member having an insulating film pattern on a surface of a conductive substrate, comprising: a step of applying an insulating film coating liquid containing a smectite clay mineral and a viscosity reducing agent onto a conductive substrate having a resist pattern formed on its surface; a step of pre-baking the coating film of the insulating film coating liquid; removing the resist by a wet method; a step of subjecting the pre-baked coating film remaining on the surface of the conductive substrate to main baking; Equipped with The temperature of the pre-baking step is 115°C to 145°C, The method for producing a conductive member, wherein the resist removal step uses an organic solvent having a solubility parameter of 9.1 to 14.

5.

4. 4. The method for producing a conductive member according to claim 3, further comprising the step of scratching the portion of the insulating film coating liquid where the pre-baked coating film is to be removed, after the pre-baking step and before the resist removal step.

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