JP2012064844A - Method of manufacturing circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a circuit board in which a via hole can be opened easily by printing method.SOLUTION: A first conductor formation process for forming a first conductor is carried out on a substrate, a first insulating film deposition process for depositing a first insulating film is then carried out to cover the first conductor. Subsequently, a through hole formation process for opening a through hole 32 in the first insulating film on the first conductor to expose the surface of the first conductor is carried out. Thereafter, a liquid-repellent process for repelling liquid from the surface of the first conductor is carried out. Finally, a second insulating film deposition process for forming a second insulating film by printing a precursor resin on a region other than the through hole 32 and then curing the precursor resin is carried out.

Description

  The present invention relates to a circuit board manufacturing method. In particular, the present invention relates to a method of manufacturing an active matrix substrate by applying a functional organic material using a printing method.

  Conventionally, in order to manufacture an active matrix substrate using a silicon semiconductor, a thin film formation process, a photolithography process, and an etching process are used as basic cycles, and this basic cycle is repeated a plurality of times. First, after the thin film is formed on the entire substrate, a photoresist pattern corresponding to the required thin film pattern is made, and most of the thin film is removed by the etching process based on the pattern, and the remaining photoresist pattern is It was removed and used as a basic cycle. That is, in this manufacturing method, most of the thin film material and all of the photoresist material have to be finally discarded, so to speak, it can be said that it is based on grand waste. In addition, a vacuum process is required for the film forming process and the etching process. These processes require a long processing time, poor productivity, and a large-scale manufacturing apparatus.

  Therefore, a method of manufacturing an active matrix substrate by a printing method has been studied as a manufacturing method that does not use the above basic cycle as much as possible, has excellent productivity, and avoids the use of a large-scale manufacturing apparatus as much as possible. Although there are various printing methods, the inkjet method is considered suitable for manufacturing an active matrix substrate. This is because the ink jet method forms the pattern in a non-contact manner on the substrate only among the various printing methods, and the probability of occurrence of defects is the lowest. This is because various printing methods other than the ink jet method make it difficult to eliminate dust entrapment and physical defects because the printing plate is brought into contact with the substrate.

  In general, an active matrix substrate is provided with a plurality of wiring layers, and these wiring layers are separated by an insulating film. In places where electrical continuity is required between the wiring layers, via holes are opened to connect the two wirings. Even when an active matrix substrate is manufactured by a printing method, conduction between the wiring layers is required. For example, in Patent Document 1, via holes are formed using a photolithography process and a dry etching process. In Patent Document 2, a via hole is formed by irradiating a laser beam to an insulating film.

JP 2008-277371 A JP 2007-266237 A

  However, in the conventional manufacturing method represented by Patent Document 1, the photolithography process has a significant effect on the functional organic material used for the active matrix substrate, and the active matrix substrate having excellent characteristics can be stably formed. There was a problem that it was difficult to manufacture. This is because the functional organic material may be irradiated with strong short-wavelength light during exposure in the photolithography process, and the functional organic material may be photodegraded. Moreover, it is because there exists a possibility that a developing solution may permeate | transmit a functional organic material at the time of image development in a photolithography process, and a functional organic material may change chemically.

  In addition, the conventional manufacturing method represented by Patent Document 2 has a problem that productivity is low and a yield is low, in addition to the problem that the manufacturing cost increases due to the use of a laser device. Normally, it is necessary to irradiate a laser beam at the same point several times to the opening of the via hole. However, since there are tens of thousands to millions of via holes in the active matrix substrate, opening them while aligning several to several hundreds with a laser device is extremely long. Time is spent. In addition, electrical continuity cannot be obtained even if the laser output fluctuates slightly. For example, if the laser output is slightly weak, the via hole cannot be opened (an insulating film remains at the bottom of the via hole). On the other hand, if it is too strong, even the electrode to be conductive is ablated. Furthermore, because of the use of laser ablation, the generation of dust is unavoidable, and the yield is lowered as a result of soiling the active matrix substrate.

  In other words, there is no conventional via hole forming method suitable for the printing method, and it is difficult to stably produce a circuit board having excellent characteristics with a high yield by the printing method. was there.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

Application Example 1 A circuit board manufacturing method according to this application example includes a first conductor forming step of forming a first conductor on a substrate, and a first insulating film formed so as to cover the first conductor. A first insulating film forming step for forming a film, a through hole forming step for exposing a surface of the first conductor by opening a through hole in the first insulating film on the first conductor, and a surface of the first conductor A lyophobic step for forming a lyophobic solution, and a second insulating film forming step for printing the precursor resin in a region other than the through-hole and curing the precursor resin after printing to form a second insulating film. Features.
According to this configuration, the via hole can be easily opened in the circuit board by a printing method, and the electronic element manufactured on the circuit board is not adversely affected. Therefore, a circuit board exhibiting excellent circuit characteristics can be stably manufactured with a high yield by a printing method.

Application Example 2 In the method of manufacturing a circuit board according to the application example, the second conductor forming process includes a second conductor forming process of forming a second conductor on the first insulating film after the liquid repellent process. It is preferable to perform the second insulating film formation step later.
In the liquid repellent step, the surface of a conductor such as a metal is selectively made liquid repellent. According to this configuration, since the second conductor is not yet formed at the time of the liquid repellent process, only the portion where the through hole is opened in the first conductor is selectively liquid repellent, and the other areas are liquid repellent. Not. Therefore, in the next second insulating film forming step, the precursor resin can be printed uniformly in the region other than the through hole, and the second insulating film can be formed without any defects in the region other than the through hole.

Application Example 3 In the method for manufacturing a circuit board according to the application example described above, it is preferable to include a third conductor forming step of forming a third conductor in a region including the through hole after the second insulating film forming step.
According to this configuration, the second insulating film is not formed in the region including the through hole, and the region naturally becomes a via hole. Therefore, electrical conduction can be established between the first conductor and the third conductor via the first insulating film and the second insulating film, and the printing method is complicated and highly functional. A circuit board having a circuit can be manufactured.

Application Example 4 In the method of manufacturing a circuit board according to the application example described above, the method includes a semiconductor film formation step of printing an organic semiconductor film after the first conductor formation step, and the first insulating film formation step after the semiconductor film formation step. It is preferable to carry out.
According to this configuration, since an organic semiconductor film can be used as the functional organic material, an organic thin film transistor can be formed on the circuit board, and a circuit board having a highly functional circuit can be manufactured. Further, in this configuration, the first conductor is used as a source / drain electrode, the active layer semiconductor film of the transistor is printed after the source / drain electrode is formed, and then the first insulating film functioning as a gate insulating film is formed. . That is, since the first conductor forming process is the first, this process does not affect the organic semiconductor film and the gate insulating film, and various methods can be applied to the first conductor forming process (the degree of freedom in the process). high). In a thin film transistor, the semiconductor film and the gate insulating film are important elements that determine transistor characteristics, but with this configuration, it is possible to completely eliminate the situation where the first conductor formation process adversely affects these important elements. A thin film transistor can be manufactured.
In a circuit using a transistor, it is an important requirement to improve circuit performance to shorten the length of the channel formation region of the transistor (distance separating the source electrode and the drain electrode in the case of an organic thin film transistor). According to this configuration, the degree of freedom in the first conductor forming process is high, and the photolithography process and the etching process can be used here prior to the formation of the organic semiconductor film and the gate insulating film. It can be very short to a few microns or less. In other words, if the photolithography process and the etching process are used only once in the manufacturing process of the circuit board, the length of the channel formation region is extremely large even if the circuit board is manufactured by the printing method for all the remaining processes. A short high-performance thin film transistor can be provided on the circuit board.

Application Example 5 In the method of manufacturing a circuit board according to the application example described above, the organic semiconductor film is an ether solvent, a ketone solvent, an ester solvent, and a fluorine solvent. However, it is preferable to exhibit poor solubility.
According to these configurations, π-conjugated molecules can be used as an organic semiconductor film, and since they can use an aromatic hydrocarbon or a saturated hydrocarbon as a solvent, an ink containing an organic semiconductor can be prepared. That is, the organic semiconductor can be printed in a shape required for the circuit board by a printing method such as an inkjet method.

Application Example 6 In the method for manufacturing a circuit board according to the application example described above, the first insulating film is preferably soluble in any of an ether solvent, a ketone solvent, an ester solvent, and a fluorine solvent.
According to these structures, an insulating material soluble in an ether solvent, a ketone solvent, an ester solvent, or a fluorine solvent, an ether resin, a ketone resin, an ester resin, or fluorine Since an insulating material made of a resin can be used in the first insulating film forming step, the first insulating film can be formed by a printing method. In addition, since the options for the first insulating film are wide, the function of the circuit board can be maximized. Further, when the first insulating film is used as a gate insulating film of a transistor, the interface between the semiconductor film and the gate insulating film is smooth and the intermediate transition layer because the first insulating film material does not dissolve the organic semiconductor film. It becomes a beautiful thing that does not exist. As a result, a thin film transistor having excellent characteristics can be manufactured over a circuit board.

Application Example 7 In the method for manufacturing a circuit board according to the application example described above, it is preferable that the first insulating film exhibits poor solubility in an alcohol solvent.
According to this configuration, it is soluble in an alcohol-based material or an alcohol-based solvent in the lyophobic process, the second conductor forming process, and the second insulating film forming process performed after the first insulating film forming process. Material can be used. That is, using these materials, the lyophobic process, the second conductor forming process, and the second insulating film forming process can be performed by a printing method. Furthermore, since the first insulating film is not damaged during these steps, the first insulating film can be maintained without deteriorating the function required for the circuit board.

Application Example 8 In the method for manufacturing a circuit board according to the application example described above, it is preferable that the first insulating film exhibits poor solubility in the precursor resin.
According to this configuration, the first insulating film is not damaged by the precursor resin during the second insulating film forming step, and the first insulating film can be maintained without deteriorating the function required for the circuit board. .

Application Example 9 In the circuit board manufacturing method according to the application example described above, it is preferable that the through-hole forming step includes a solvent dropping step of dropping a solvent that dissolves the first insulating film onto the first insulating film.
Since the solvent can be dropped by an inkjet method, according to this configuration, a fine through hole can be easily formed by a printing method.

Application Example 10 In the method for manufacturing a circuit board according to the application example described above, it is preferable that the through hole forming process includes an etching process for uniformly etching the first insulating film, and the etching process is performed after the solvent dropping process.
In the solvent dropping step, the first insulating film material can be moved from the center of the landing point of the droplet to the periphery thereof, and a through hole can be provided in the vicinity of the center of the landing point. However, there may be a situation in which the first insulating film remains thin in the vicinity of the central portion in accordance with fluctuations in the amount of droplets and fluctuations in drying conditions (temperature and air volume). Therefore, according to this configuration, such a thin film that is slightly remaining can be removed, and a through-hole can be reliably formed.

Application Example 11 In the method for manufacturing a circuit board according to the application example described above, it is preferable that the liquid repellency step includes bringing the surface of the first conductor into contact with a solution containing a thiol compound or a disulfide compound.
According to this configuration, the sulfur atom of the thiol compound or disulfide compound is quickly bonded to the metal atom, so that only the surface of the first conductor is easily made liquid repellent easily by a short contact of several seconds to several minutes. I can do things.

Application Example 12 In the method for manufacturing a circuit board according to the application example, it is preferable that the thiol compound includes a fluorinated alkyl chain.
Since the fluorinated alkyl chain lowers the surface tension, according to this configuration, the liquid repellency of the surface to which the thiol compound is bonded can be made extremely high.

Application Example 13 In the circuit board manufacturing method according to the application example described above, it is preferable that the disulfide compound includes a fluorinated alkyl chain.
Since the fluorinated alkyl chain lowers the surface tension, according to this configuration, the liquid repellency of the surface to which the disulfide compound is bonded can be made extremely high.

Application Example 14 In the circuit board manufacturing method according to the application example described above, the precursor resin preferably includes a monomer having a hydroxyl group.
Although the second insulating film is formed on the first insulating film, the first insulating film is stable against alcohol-based materials. Therefore, according to this configuration, the precursor resin damages the first insulating film. (Melting the first insulating film) can be avoided.

Application Example 15 In the method for manufacturing a circuit board according to the application example, the precursor resin is preferably soluble in an alcohol solvent.
According to this configuration, since the precursor resin can be diluted with an alcohol solvent, the concentration of the solution can be adjusted relatively freely, and various printing methods can be applied to the second insulating film forming step. Further, since the first insulating film is stable with respect to the alcohol-based material, it is possible to avoid the second insulating film forming step from damaging the first insulating film (melting the first insulating film).

Application Example 16 In the method for manufacturing a circuit board according to the application example, the precursor resin is preferably a photocurable resin.
According to this configuration, the second insulating film can be formed quickly and easily by irradiating light after printing the precursor resin.

Application Example 17 In the method for manufacturing a circuit board according to the application example, the precursor resin is preferably a thermosetting resin.
According to this structure, after printing precursor resin, a 2nd insulating film can be easily formed by simple heat processing.

Application Example 18 In the circuit board manufacturing method according to the application example, it is preferable that the circuit board includes a transistor including a gate insulating film, and the first insulating film functions as the gate insulating film.
According to this configuration, a circuit board having a high-function circuit can be realized. Further, since the circuit board is manufactured by the printing method except for the first conductor forming step, it is estimated that the productivity is very high and a circuit board having a high-function circuit can be manufactured in one day. The process is easy to automate, and the main printing method is the ink jet method, which reduces waste.

Sectional drawing which showed typically the manufacturing method of the circuit board concerning Embodiment 1. FIG. Sectional drawing which showed typically the manufacturing method of the circuit board concerning Embodiment 1. FIG. Sectional drawing which showed typically the manufacturing method of the circuit board concerning Embodiment 1. FIG. FIG. 3 is a plan view schematically showing the circuit board manufacturing method according to the first embodiment. FIG. 3 is a plan view schematically showing the circuit board manufacturing method according to the first embodiment. The figure explaining the state at the time of completion | finish of a liquid repelling process in the manufacturing method of the circuit board concerning Embodiment 1. FIG. The figure explaining the principle of a through-hole formation process in the manufacturing method of the circuit board concerning Embodiment 1. FIG. FIG. 2 is a plan view schematically showing an active matrix substrate manufactured using the circuit board manufacturing method described in detail in the first embodiment. FIG. 3 is a cross-sectional view schematically showing an electro-optical device using an active matrix substrate manufactured using the circuit board manufacturing method described in detail in the first embodiment. FIG. 2 is a perspective view schematically showing an electronic apparatus using an electro-optical device, where (a) is a front perspective view and (b) is a rear perspective view. Sectional drawing of the circuit board concerning the modification 1. FIG. The top view of the circuit board concerning the modification 2. FIG. The top view of the circuit board concerning the modification 3. FIG. Sectional drawing of the circuit board concerning the modification 3. FIG. Sectional drawing of the circuit board concerning the modification 8. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the scales are different for each layer and each member so that each layer and each member has a size that can be recognized on the drawing.

(Embodiment 1)
1, 2, and 3 are cross-sectional views schematically showing a circuit board manufacturing method according to the first embodiment. 4 and 5 are plan views schematically showing the circuit board manufacturing method according to the first embodiment. 1 to 3 correspond to the cross sections taken along lines AA ′ and BB ′ in FIGS. 4 and 5, and for the sake of convenience, only the positions of AA ′ and BB ′ are shown in FIG. Is described. Hereinafter, a method for manufacturing a circuit board will be described with reference to FIGS.

"Overview"
First, the outline will be described with reference to FIG.
The present invention relates to a method of manufacturing a circuit board 1 including two types of conductive layers and two types of insulating layers that separate them. The circuit board 1 is mainly manufactured by using a printing method, and relates to a technique of opening two via holes 31 in two types of insulating layers and electrically connecting the two types of conductive layers to each other so as to be suitable for the manufacturing method. In FIG. 3J, the two types of conductive layers are a source / drain electrode 11 made of a first conductor and a pixel electrode 13 being a third conductor. The two types of insulating layers are a gate insulating film 21 that is a first insulating film and an interlayer insulating film 22 that is a second insulating film. The gate insulating film 21 covers a first conductor such as the source / drain electrode 11, an interlayer insulating film 22 is provided thereon, and a pixel electrode 13 is further formed thereon. A via hole 31 is opened on the source / drain electrode 11, and the source / drain electrode 11 and the pixel electrode 13 are connected via the via hole 31. The gate electrode 12 and the like are formed of the second conductor, and the gate electrode 12 and the pixel electrode 13 are insulated by the interlayer insulating film 22. That is, the first insulating film insulates the first conductor from the second conductor, and the second insulating film insulates the second conductor from the third conductor.

  The following steps are performed to manufacture such a circuit board 1. First, as a first conductor forming step, a source / drain electrode 11 and the like are formed on a substrate. Next, as the first insulating film forming step, the gate insulating film 21 is formed so as to cover the first conductor. Next, as a through hole forming step, a through hole 32 is opened in the gate insulating film 21 on the source / drain electrode 11 to expose the surface of the source / drain electrode 11. Thereafter, a lyophobic process for lyophobizing the surface of the source / drain electrode 11 is performed. Next, as a second insulating film forming step, the precursor resin of the interlayer insulating film 22 is printed in a region other than the through holes 32, and after the printing, the precursor resin is cured to form a second insulating film. The precursor resin has a low viscosity and spreads on the substrate surface during printing. However, the portion where the source / drain electrodes 11 are opened is not repelled because the liquid-repellent treatment is applied, and the precursor resin is applied to the portion. Not. Thus, the via hole 31 is easily and reliably formed. After the via hole 31 is formed, the pixel electrode 13 is formed, and the two kinds of conductive layers are electrically connected.

  Hereinafter, the manufacturing method of the circuit board 1 will be described in detail for each process. In this embodiment, as a preferred example, a case where an active matrix substrate having an upper gate type and having a thin film transistor (organic TFT) using an organic substance as a semiconductor film is applied to the circuit substrate 1 will be described.

"First conductor formation process and first insulating film formation process"
FIG. 1A shows a process up to the first insulating film forming process in the manufacturing process of the circuit board of the present embodiment. The substrate 10 is a polyethylene naphthalate (PEN) film. As the substrate 10, any substrate such as a glass substrate, a metal substrate such as aluminum or stainless steel, a semiconductor substrate such as silicon or GaAs, or a plastic substrate can be used, but the organic TFT can be formed at a low temperature with a simple method. Therefore, among these, it is preferable to use a plastic substrate that is inexpensive, lightweight, and highly flexible.

  Examples of plastic substrates other than PEN films include polyolefins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), cyclic polyolefin, modified polyolefin, polyvinyl chloride, poly Vinylidene chloride, polystyrene, polyamide, polyimide, polyamideimide, polycarbonate, poly- (4-methylbenten-1), ionomer, acrylic resin, polymethyl methacrylate, acrylic-styrene copolymer (AS resin), butadiene-styrene copolymer Polyesters such as polymers, polio copolymers (EVOH), polyethylene terephthalate, polybutylene terephthalate, precyclohexane terephthalate (PCT), polyethers, polyether keto , Polyether ether ketone, polyether imide, polyacetal, polyphenylene oxide, modified polyphenylene oxide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluororesins, styrene, polyolefin, Various thermoplastic elastomers such as polyvinyl chloride, polyurethane, fluoro rubber, chlorinated polyethylene, epoxy resin, phenol resin, urea resin, melamine resin, unsaturated polyester, silicone resin, polyurethane, etc. A copolymer, a blend, a polymer alloy, and the like. Among these, a laminate in which one kind or two or more kinds are laminated can be used.

  A first conductor made of gold (Au) is provided on the substrate 10, and an electrode pad 111, a source / drain electrode 11, an unillustrated data line and other wirings connected to the outside are provided by these. Is formed. As the first conductor material, a material capable of bonding with a sulfur atom of a thiol compound or a disulfide compound is used. Besides gold, Cr, Al, Ta, Mo, Nb, Cu, Ag, Pt, Pd, Ni , And alloys using these metals are used. In addition to these, an oxide conductor such as indium tin oxide (ITO), tin oxide, or zinc oxide may be used as the first conductor material. These metal films and oxide conductors are patterned into a predetermined shape through a photolithography process and a wet or dry etching process after depositing a uniform thin film by vacuum deposition or sputtering. Alternatively, for a material that is difficult to etch, a metal film may be deposited (mask deposition) through a mask having holes in a predetermined shape. In addition, a dispersion of silver (Ag) nanocolloid may be printed by microcontact printing or convex plate reverse printing. This corresponds to the first conductor forming step. Here, gold was vacuum-deposited on the entire surface of the PEN film, and then the first conductor was formed through a photolithography process and a wet etching process. Note that a mixed solution of iodine and alkali iodide (ammonium iodide) was used for wet etching of gold.

  After the first conductor forming step, a semiconductor film forming step for printing the organic semiconductor film 41 is performed. A semiconductor material is printed by an inkjet method so as to connect the source / drain electrodes 11 (fill the channel formation region). Here, the organic semiconductor film 41 is poly (9,9-dioctylfluorene-cordithiophene) (F8T2), which is a polymer organic semiconductor exhibiting P-type semiconductor characteristics. Other P-type polymer organic semiconductor materials that can be used include poly (3-hexylthiophene) (P3HT), poly [5,5′-bis (3-dodecyl-2tinyl) -2,2 ′. -Bithiophene] (PQT-12), PBTTT and the like. When a soluble low molecular weight organic semiconductor material that can be printed is used, BTBT, thiophene oligomer, and the like can be given. Organic semiconductors have a π bond, so they are most soluble in aromatic hydrocarbons (toluene, xylene, mesitylene, cyclohexylbenzene, etc.), and then consist of cyclic saturated hydrocarbons (cyclohexane, methylcyclohexane, ethylcyclohexane, decalin, etc.) It is dissolved in a solvent and printed. The concentration of the semiconductor material at the time of dissolution is preferably in the range of 0.3% to 2.5%, and the ideal range is 0.5% to 1.5%. Since the first insulating film is applied in the next step, it is desirable that the organic semiconductor has high solvent selectivity. Specifically, it is well soluble in aromatic hydrocarbons and cyclic saturated hydrocarbons for printing semiconductor films as described above, and water, alcohol-based solvents, ether-based to be stable after the next step. It is desired to be insoluble in solvents, ketone solvents, ester solvents, and fluorine solvents. From the viewpoint of solvent selectivity, a polymer type organic semiconductor material is preferable to a soluble low molecular weight organic semiconductor material. The F8T2 used here dissolves well in decalin and is stable to ketone solvents and ester materials. The semiconductor film was formed by printing F8T2 dissolved in decalin at a concentration of 2% by an inkjet method. The thickness of the semiconductor film is preferably in the range of 10 nm to 200 nm, and the ideal range is 30 nm to 60 nm. The thickness here was 50 nm.

  A first insulating film forming step is performed after the semiconductor film forming step. A gate insulating film 21 which is a first insulating film is provided to cover the semiconductor film. Here, polymethyl methacrylate (PMMA) having a thickness of 500 nm was formed by spin coating. In this way, the gate insulating film 21 is uniformly coated with the insulating polymer over the entire substrate. Since the organic semiconductor film 41 must not be dissolved at this time, the organic semiconductor material is insulatively soluble in a solvent in which the organic semiconductor material is hardly soluble (alcohol solvent, ether solvent, ketone solvent, ester solvent, fluorine solvent). Use functional polymers. Furthermore, the liquid repellency process, the second conductor forming process (gate electrode forming process), the second insulating film forming process (application and curing of the precursor resin in the interlayer insulating film forming process), etc. performed thereafter The gate insulating film 21 must be stable with respect to various processes to be performed. In these steps, alcoholic materials, glycols, and glycerin are used, so that the insulating polymer needs to be stable against these. That is, the first insulating film is hardly soluble in alcohol solvents and materials (not easily soluble), and is soluble (soluble in any of ether solvents, ketone solvents, ester solvents, and fluorine solvents). ) Material. Specifically, acrylic polymers such as PMMA, perfluorinated polymers represented by Cytop (trade name of Asahi Glass), or fluorine-based aromatics as disclosed in JP 2010-74088 A Polymers, and phenolic polymers such as polyvinylphenol (PVP) and novolak resins can be used. Since acrylic polymers have ester groups, they are well soluble in ester solvents such as butyl acetate and hardly soluble in alcoholic materials such as ethanol and propylene glycol. Although all fluorine-based polymers can be dissolved in fluorine-based solvents, they are insoluble (not soluble) in many solvents such as alcohol-based materials. In addition, fluorine aromatic polymers have carbonyl groups and ester groups, so they are well soluble in ketone solvents and ester solvents in addition to fluorine solvents, but only slightly soluble in alcohol solvents such as ethanol. Indicates.

  Since the phenolic polymer is soluble in alcohol, it cannot be used as it is for the first insulating film, but can be applied by insolubilization. That is, first, a crosslinking agent is mixed with a phenol polymer and applied. Next, after completing the through-hole forming step, the chemical reaction is accelerated by heating or the like to crosslink. Thus, the first insulating film is insolubilized and becomes stable with respect to the subsequent steps.

  Olefin polymers can be used as ether solvents, ketone solvents, and ester solvents by copolymerizing with materials having polar functional groups such as hydroxyl groups and carbonyl groups, or by adding these as side chains. Can be melted. Therefore, an olefin polymer subjected to such treatment can also be used as the first insulating film. In this case, a cycloolefin polymer is suitable.

  As will be described later, the precursor resin is a monomer provided with a hydroxyl group, which is synthesized to form a second insulating film. However, since the first insulating film is stable against alcohol-based materials, it is also difficult for the precursor resin. It will show solubility. The thickness of the first insulating film is preferably in the range of 100 nm to 1000 nm, and more preferably in the range of 200 nm to 800 nm.

"Through hole formation process"
FIGS. 1B and 1C show a through hole forming process in the process of manufacturing the circuit board of the present embodiment. As shown in FIG. 1B, the through-hole forming step starts with a solvent dropping step of dropping a solvent that dissolves the first insulating film onto the first insulating film. Specifically, γ-butyrolactone is dropped onto the first insulating film at a location where the through hole is to be opened by the inkjet method 51. In FIG. 1B, about 25 pL of γ-butyrolactone droplet 52 was dropped three times on the source / drain electrode 11.

  The solvent used in the through hole forming step is a solvent that can dissolve the first insulating film (either an ether solvent, a ketone solvent, an ester solvent, or a fluorine solvent), and is ejected from these by the inkjet method 51. It is desirable to use a solvent having a viscosity in the range of 1 mPa · s to 5 mPa · s, which is suitable for the purpose. If the viscosity is 1 mPa · s or more, the solvent can be easily dropped by the ink jet method 51, and if it is 5 mPa · s or less, a micro flow is generated in the solution, and the through hole 32 can be opened. Furthermore, in order to form fine through holes, the surface tension of the solvent is preferably 35 mN / m or more, ideally 40 mN / m or more. Moreover, in order to form a deep through-hole, it is preferable that the boiling point of a solvent is higher than 180 degreeC. The dropped γ-butyrolactone was a cyclic ester having a viscosity of 1.7 mPa · s, a surface tension of 44 mN / m, and a boiling point of 207 ° C. Although it depends on the solvent evaporation rate determined by the temperature and wind speed during the through hole formation process, these conditions are satisfied and the normal working environment (temperature 20 ° C. to 30 ° C., relative humidity 30% to 80%, air When a drop 52 of about 20 pL is dropped once with a downflow air volume of 0.01 m / s to 0.1 m / s), a hole with a depth of about 200 nm to 400 nm can be formed. Once dropped, a hole having a depth of about 400 nm to 600 nm can be formed. Accordingly, when the first insulating film has a thickness of less than about 400 nm and a droplet 52 of about 40 pL is used, a through-hole that reaches the source / drain electrode 11 with a single solvent drop, as shown in FIG. 32 can be formed. When the first insulating film is thicker or the solubility is insufficient, the droplet 52 is dropped at the same position a plurality of times to form a through hole.

  In general, the volume of the droplet 52 that can be easily ejected by the inkjet method 51 is about 6 pL to 14 pL (when a nozzle having a diameter of 25 μm is used). Therefore, for example, “dropping a 25 pL droplet 52 once” strictly speaking, four 6.3 pL droplets 52 are continuously discharged into the first discharged droplet and dried. Means things. Further, dropping the 25 pL droplet 52 three times means that a cycle in which four droplets of 6.3 pL 52 are continuously discharged to the same spot and dried for several seconds is repeated three times. Of course, if the nozzle diameter or the driving method of the ink jet method 51 is changed, a droplet having a larger volume (for example, a droplet of 25 pL) can be ejected at a time, and thus this method may be applied.

  The formation principle of the through hole 32 will be described in detail later.

After the solvent dropping step, as shown in FIG. 1C, a through hole 32 is formed at a position where the solvent is dropped. That is, the through hole 32 is opened at a position to be connected to the third conductor on the surface of the first conductor. However, a complete through hole 32 may not be formed in many through holes 32 that range from tens of thousands to millions. At first glance, even though the through hole 32 appears to reach the bottom, a very thin insulating thin film may remain on the surface of the first conductor. In order to remove this, an etching process for uniformly etching the first insulating film is performed after the solvent dropping process. Here, the entire substrate was exposed to oxygen plasma, and the polymer layer possibly remaining on the surface of the first insulating film and the surface of the first conductor was scraped off. Specifically, the substrate was exposed to oxygen plasma of 40 W / cm ² for 2 minutes. Thereby, the polymer layer remaining in a thin skin state can be completely removed.

  The etching process may be ozone irradiation treatment in addition to the above-described oxygen plasma treatment. Further, it may be rinsed with a solvent whose solubility is controlled. At this time, a solvent that is insoluble in the semiconductor film and soluble in the first insulating film (soluble solvent, such as an ether solvent, a ketone solvent, or an ester solvent) and the semiconductor film is also in the first insulation. The membrane is rinsed for a short time with a mixed solvent in which an insoluble solvent (insoluble solvent such as an alcohol solvent) is mixed at an appropriate ratio. As an example of the mixed solvent, the volume ratio of the insoluble solvent to the soluble solvent is set to a ratio of about 1: 1 to 10: 1. For example, it is possible to obtain a solvent whose solubility is controlled by mixing ethanol with 2 in acetone with 1 as the acetone. When the substrate is immersed in this mixed solvent for about 1 to 5 minutes, the thin insulating polymer layer is removed cleanly. In addition to being immersed in the mixed solvent, the mixed solvent may be supplied to the substrate surface in a shower form or a spin coat form.

  As described above, when a reactive material (such as a phenolic polymer with a crosslinking agent) is used for the first insulating film, a heat treatment for accelerating the reaction is performed after the etching process.

"Liquid repellent process"
FIG. 1D shows a liquid repellency process in the manufacturing process of the circuit board of the present embodiment. FIG. 6 is a diagram illustrating in detail the state at the end of the lyophobic process in the circuit board manufacturing method according to the first embodiment. As shown in FIG. 1D, in the liquid repellent step, the surface of the first conductor is brought into contact with a solution 61 containing a thiol compound or a disulfide compound. The simplest technique is to immerse the substrate with through holes formed in a solution 61 containing a thiol compound or disulfide compound for a short period of time from several seconds to several minutes. Since the sulfur atom of the thiol compound or disulfide compound is quickly bonded to the metal atom forming the first conductor, the surface of the first conductor is easily made liquid repellent by such a short contact treatment. It is more preferable that the thiol compound or disulfide compound contains a fluorinated alkyl chain (fluorinated alkyl thiol or fluorinated alkyl disulfide, hereinafter, abbreviated as fluorinated alkyl thiol 62), resulting in increased liquid repellency. here,
_{HS- (CH 2) 6 - (} CF 2) 7 -CF 3
The alkyl fluoride thiol 62 represented by the chemical formula of

  As shown in FIG. 6B, the sulfur of the thiol compound or disulfide compound is firmly bonded to a metal such as gold, and the surface covered with the fluorinated alkylthiol 62 is covered with the fluorinated alkyl chain, and the surface energy is increased. Lower. As a result, the contact angle of the metal surface with water increases from about 100 ° to about 140 °. As described above, the lyophobic treatment is a treatment for lowering the surface energy of the first conductor so that the contact angle with water is 90 ° or more.

  The fluorinated alkyl thiol 62 is dissolved in an alcohol solvent (ethanol, isopropyl alcohol, butanol, etc.) at a concentration of 0.005% to 1%. The concentration is more preferably in the range of 0.05% to 0.5%. When the substrate is immersed in a solution having a concentration of about 0.2%, as shown in FIG. 6A, the exposed portion where the source / drain electrode 11 of the through-hole 32 is exposed almost instantaneously (less than 1 second). Covered with fluorinated alkylthiol 62 (in a very short time). However, from the standpoint of stably performing the process, the immersion time is preferably 1 minute or longer. Further, from the standpoint of improving productivity and minimizing substrate damage due to dipping, it is desirable that the dipping time be 3 minutes or less. Here, the above-mentioned alkylthiol was dissolved in ethanol at a concentration of 0.2%.

  Since the fluorinated alkyl thiol 62 is also dissolved in the fluorine-based solvent, it may be used as a diluted solvent for the fluorinated alkyl thiol 62. In this case, however, the first insulating film is hardly soluble in both alcohol solvents and alcohol materials and fluorine solvents, and is soluble in either ether solvents, ketone solvents, or ester solvents. Must be a polymeric material exhibiting Specifically, it is an acrylic polymer, a fluorine-based aromatic polymer, a phenol-based polymer, or an olefin-based polymer.

The thiol compound or disulfide compound does not necessarily have to be substituted with fluorine in the main chain extending from the sulfur atom. If the main chain has a contact angle with respect to water of 90 ° or more, it can be used for the liquid repellency step without using fluoride. When the main chain extending from the sulfur atom is fluorinated, the contact angle with water can be easily increased to 110 ° or more, and excellent liquid repellency can be exhibited. The fluorinated alkyl thiol 62 includes
_{HS- (CH 2) k -O- (} CH 2) l - (CF 2) m -CF 3 or _{HS- (CH 2) k + l} - (CF 2) m -CF 3
A material represented by the chemical formula can be used. In order to form a dense SAM film by introducing a soft and small-volume alkyl chain to a hard and large-volume fluorinated alkyl, the value of k + 1 is preferably in the range of 4 to 16, The value of is preferably in the range of 0 or more and 3 or less. In order to exhibit excellent liquid repellency, the value of m needs to be 1 or more, and in order to dissolve in an alcohol solvent, the value of m is preferably 11 or less. When the value of m is 12 or more, the solubility in an alcohol-based solvent is lowered, making it difficult to use in the liquid repellency step. Instead of fluorinated alkyl, some or all of these may be substituted with fluorinated alicyclic hydrocarbons.

  Here, the substrate is immersed in a solution containing the fluorinated alkyl thiol 62. However, when some of the exposed first conductors are made to be liquid repellent and the rest are not to be made liquid repellent. The solution 61 containing a thiol compound or a disulfide compound may be dropped by the ink jet method only in the 32 parts of the through hole to be made liquid repellent.

  As described above, when an oxide conductor such as indium tin oxide (ITO), tin oxide, or zinc oxide is used as the first conductor material, the oxide is used instead of the thiol compound or disulfide compound. It is made liquid repellent using a compound such as adsorbing phosphoric acid, phosphonic acid, fatty acid, or organic silane. Specifically, a phosphoric acid ester having a fluorinated alkyl group, or a phosphoric acid ester salt having a fluorinated alkyl group, an ether of an alcohol having a fluorinated alkyl group and phosphoric acid, a phosphonic acid having a fluorinated alkyl group, Phosphonic acid ester having fluorinated alkyl group, phosphonic acid ester salt having fluorinated alkyl group, compound having carboxy group and fluorinated alkyl group (fatty acid having fluorinated alkyl group), silane cup having fluorinated alkyl group A compound such as a ring agent is used.

"Hydrophilic electrode formation process"
2E and 2F show a hydrophilic electrode forming process in the process of manufacturing the circuit board according to the present embodiment. FIG. 4A is a plan view corresponding to FIG. In the hydrophilic electrode forming step, as shown in FIG. 2 (e), the first insulating film in a place to be connected to the second conductor is removed from the first conductor to remove the hydrophilic (repellent). This is a step of forming a through-hole having an electrode surface that is not liquid.

  The circuit board 1 may require connection between the first conductor and the second conductor. For example, in an electrode pad 111 that connects a scanning line to an external control circuit, it may be desired to connect the electrode pad of the first conductor and the scanning line of the second conductor. For example, when configuring a series circuit of inverters or a pixel circuit of an organic EL display, the output (drain electrode, first conductor) of one transistor is connected to the input (gate electrode, second conductor) of another transistor. It is sometimes done. As described above, depending on the circuit board 1, there is a case where the connection between the first conductor and the second conductor is required. At this time, this hydrophilic electrode forming step is performed. This is because the electrical connection stability between the first conductor and the second conductor is increased and the next second conductor forming step is desired to be performed by a printing method. When the surface of the first conductor is liquid repellent, poor connection is likely to occur. Therefore, it is desirable that the surface of the first conductor is hydrophilic in order to obtain an electrical connection with a high yield. Further, since the conductor printing ink using water or an alcohol solvent is used in the printing method of the second conductor, if the surface of the first conductor is liquid repellent, the conductor ink is repelled, and the through hole is formed. The first conductor cannot be drawn on the part. For these reasons, it is desirable that the surface of the first conductor where the connection between the first conductor and the second conductor is required be hydrophilic.

  In the hydrophilic electrode forming step, as shown in FIG. 2 (e), a droplet 52 of a solvent that dissolves the first insulating film is formed on the first electrode on which the hydrophilic electrode is to be formed (using the inkjet method 51). For example, it is a step of dropping a first insulating film on the electrode pad 111) to form a hydrophilic electrode opening. Here, using the same solvent (γ-butyrolactone) as in the through-hole forming step, a hydrophilic electrode opening was provided by the same method (a predetermined amount of solvent was dropped by the inkjet method 51 a predetermined number of times). In this way, as shown in FIG. 2 (f) and FIG. 4 (a), the through hole 32 is provided at a site where a hydrophilic electrode opening is required, such as on the electrode pad 111.

  In addition, as described above, when the liquid repellent process can be selectively made liquid repellent by using the ink jet method, this hydrophilic electrode forming process is unnecessary. In that case, all the through-holes 32 are opened during the through-hole forming step, and the liquid-repellent electrode surface and the hydrophilic electrode surface are separately formed using the ink jet method during the liquid-repellent step. Specifically, since the electrode surface that is not subjected to any treatment is hydrophilic, the fluorinated alkylthiol 62 is dropped only in the through-hole 32 where the liquid-repellent electrode surface is desired.

"Second conductor formation process"
FIG. 2G shows a second conductor forming step in the manufacturing process of the circuit board 1 of the present embodiment. FIG. 4B is a plan view corresponding to FIG. The second conductor forming step is a step of forming the second conductor on the first insulating film after the liquid repellent step.

  As shown in FIG. 2G, the second conductor is formed by dripping the ink 53 for the conductor by the ink jet method 51 and then firing it, thereby forming the gate electrode 12 or a scanning line (not shown). A pattern of two conductors is formed. As the conductor ink 53, it is desirable to use an ink in which silver nanoparticles that can be baked at a low temperature are dispersed. Here, a conductor ink 53 (hereinafter abbreviated as silver ink) in which silver nanoparticles are dispersed in a mixed solvent of water and propanediol was used. In order to print a thin line having a line width of about 40 μm by the ink-jet method 51, it is desirable that the surface tension of the conductor ink 53 be in the range of 40 mN / m to 60 mN / m. In this way, the wetting and spreading of the ink dropped on the organic insulator can be controlled to be small, and a thin wiring is drawn. In addition, in order to print by the ink jet method 51, it is necessary that the viscosity of the conductor ink 53 is adjusted within a range of 1 mPs · s to 20 mPs · s. Furthermore, in order to prevent functional deterioration of organic substances such as semiconductor materials during firing of the conductor ink 53, it is desirable that the conductor ink 53 can be fired under processing conditions within a temperature range of 80 ° C to 150 ° C. The silver ink used here became a sufficiently low conductor having a specific resistance of 50 μΩcm or less after firing by performing a heat treatment at 100 ° C. for 30 minutes in the air.

  As the dispersion medium for the conductor ink 53, water or glycol having a large surface tension of 72 mN / m, or a substance containing a mixed solvent thereof is preferable because of its large surface tension. When it is difficult to draw a continuous line because the viscosity is too low or the surface tension is too high with water alone, an alcohol solvent, a diol solvent, or a glycerin solvent is added to water.

  In addition to silver ink, ink in which carbon (carbon black, graphite, carbon nanotube, fullerene, graphene, or the like) is dispersed in the above-described dispersion medium can also be used. In the present embodiment, since the surface of the second conductor was not desired to be liquid repellent, the liquid repellent step was performed prior to the second conductor forming step. In the case of using an ink in which carbon is dispersed, the surface of the carbon ink is not liquid repellent even if a liquid repellent process is performed. Therefore, in this case, the liquid repellent process may be performed after the second conductor forming process.

  As shown in FIG. 4B, silver ink is printed from the electrode pad 111 having a hydrophilic electrode opening to the scanning line and the gate electrode 12. Thereby, the electrode pad 111 made of the first conductor can be connected to the scanning line and the gate electrode 12. The wiring and electrode pads connected to the external control circuit are formed with the pattern of the first conductor using a photolithography process, so high-density wiring with a line and space of 50 μm or less is possible. This is useful for miniaturization of electronic equipment using the circuit board 1.

"Second insulating film formation process"
FIGS. 3H and 3I show a second insulating film forming step in the circuit board manufacturing process of the present embodiment. FIG. 5C is a plan view corresponding to FIG. If there is a second conductor on the circuit board, the second insulating film forming step is performed after the second conductor forming step.

  The second insulating film is an interlayer insulating film, and mainly electrically separates the second conductor and the third conductor. In order to form the second insulating film, as shown in FIG. 3 (h), first, the precursor resin of the interlayer insulating film is printed so as to avoid the through holes 32, and then as shown in FIG. 3 (i). Then, the reaction of the precursor resin is promoted to form a second insulating film. The precursor resin contains a monomer having a hydroxyl group and is soluble in an alcohol solvent. The precursor resin is preferably a photocurable resin. Here, an ultraviolet curable resin (hereinafter abbreviated as UV ink 54) containing a hydroxy-type acrylic monomer (acrylic acid or an ester of methacrylic acid and a polyhydric alcohol) that is soluble in an alcohol solvent is used as a precursor resin. did.

  As shown in FIG. 3 (h), first, the UV ink 54 is dropped by an ink jet method 51 into a region other than the through hole 32 (that is, a region where the first insulating film and the second conductor are present). The precursor resin such as the UV ink 54 is prepared to be suitable for the ink jet method 51 and contains a monomer as a main component. The polymer component is not included in the precursor resin, or a small amount is included. The monomer preferably contains an —OH group in order to increase polarity. As such a monomer, diethylene glycol mono 2-ethylhexyl ether acrylate, tetraethylene glycol monophenyl ether acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, or the like may be used. . Since such an acrylic monomer contains an —OH group, the polarity is high, and the solubility parameter (SP value) is 9.5 or more. Therefore, the polymer of the gate insulating film 21 is not dissolved, and the adhesiveness with the gate insulating film 21 is high.

  In this way, the precursor resin is a monomer having an SP value of 9.5 or more, which has a surface tension equivalent to that of an organic solvent (20 mN / m to 35 mN / m) and a viscosity equivalent to 10 mPa · s to 30 mPa · s. In this way, the ink jet method 51 can be easily used to discharge the ink. Since the surface tension is relatively low and the viscosity is low, the UV ink 54 spreads uniformly on the organic insulator or metal material to a diameter of 5 times or more after landing. On the other hand, since the wetting angle is 45 ° or more at the exposed portion of the lyophobic electrode, spreading of the precursor resin is suppressed. As a result, the precursor resin spreads over the first insulating film and the second conductor without the exposed portion of the lyophobic electrode being covered with the UV ink 54. In this way, a uniform liquid film is printed by the inkjet method 51.

  The thickness of the second insulating film is controlled by adjusting the dropping amount of the UV ink 54. When the interlayer insulating film 22 of the TFT formed on the film is used as the second insulating film as in the present embodiment, the first conductor or the In terms of minimizing the parasitic capacitance between the second conductor and the third conductor, the thickness of the interlayer insulating film 22 is preferably 1 μm or more. When the thickness of the interlayer insulating film 22 exceeds 20 μm, the substrate is warped due to the influence of the volume change when the UV ink 54 is cured. If the amount of ink dropped is too large, the wetting angle at the exposed portion will be exceeded, and it will not be possible to maintain a state in which the exposed portion of the lyophobic electrode is not covered with the UV ink 54. The wetting angle of the precursor resin on the organic insulator is 45 ° or more and 70 ° or 90 ° or less. When the thickness of the liquid film exceeds 20 μm, the contact angle that is theoretically determined from the weight of the liquid and the surface tension exceeds the previous wetting angle. In this case, since the exposed portion of the lyophobic electrode is also covered with the precursor resin, it is necessary to suppress the dripping amount so that the theoretically determined contact angle does not exceed the previous wetting angle.

  Next, as shown in FIG. 3I, the UV ink 54 is irradiated with ultraviolet rays 55 to cure the UV ink 54, thereby forming the via hole 31. In order to completely cure, heat treatment may be performed in addition to ultraviolet irradiation. Since ultraviolet rays 55 are irradiated after printing the UV ink 54, a flat second insulating film is obtained except for the exposed portions of the electrodes. Here, after the UV ink 54 is printed, the ultraviolet rays 55 are collectively irradiated. However, the ultraviolet rays 55 may be irradiated simultaneously with the printing of the UV ink 54. In this case, wetting spread is suppressed by a chemical reaction, and the controllability of not applying the UV ink 54 to the exposed portion of the electrode is increased. By providing an ultraviolet irradiation device using an LED as a light source adjacent to an inkjet head, a small-sized device can be realized.

  The UV ink 54 is not limited to an acrylic monomer, and an epoxy monomer or the like may be used. Furthermore, the precursor resin is not limited to the UV ink 54, and may be a thermosetting resin. In these cases as well, the precursor resin must not dissolve the gate insulating film, so that the polarity is increased by introducing a hydroxyl group into the epoxy monomer or thermosetting resin.

  In order to form the second insulating film having a thickness of 1 μm or more by the inkjet method, in addition to the above-described method using a curable monomer, a method using a dispersion system of surface-treated fine particles and a polymer material is used. There may be. For example, silica fine particles are surface-treated with a surfactant such as lecithin so as to be dispersed in an organic solvent, and this is mixed with a polymer resin for a binder to obtain a dispersion. This dispersion becomes a low-viscosity precursor resin and can be printed by an ink jet method. However, after it is dried, the thickness of the second insulating film can be made relatively large, such as 1 μm or more.

"Third conductor formation process"
FIG. 3J illustrates a third conductor forming process in the process of manufacturing the circuit board according to the present embodiment. FIG. 5D is a plan view corresponding to FIG. After the second insulating film is formed, a third conductor is formed in a region including the via hole 31. Here, the third conductor is the pixel electrode 13.

  The pixel electrode 13 is formed by screen printing using carbon ink. Screen printing has high printing speed and excellent productivity. On the other hand, since printing is performed with the screen in contact with the substrate, there is a risk of damaging the thin film layer when this printing method is used in the production of organic TFTs. However, in this embodiment, since the hardened thick second insulating film covers the outermost surface, even a method of printing by contact such as screen printing does not lead to defects of the organic TFT, and has excellent productivity. You can enjoy the advantage of easy printing process. Moreover, since the reaction of the second insulating film is completed, the solvent of the carbon ink is not particularly limited.

  In the carbon ink, carbon (carbon black, graphite, carbon nanotube, fullerene, graphene, etc.) is dispersed in an organic solvent. As the organic solvent, a ketone solvent, an ester solvent, an ether solvent, or the like is used. The viscosity of the carbon ink is adjusted from 2000 mPa · s to 20000 mPa · s so as to be suitable for screen printing. In this case, even if printing is performed on the surface of the liquid-repellent first electrode, the carbon ink is not repelled and is electrically connected. Further, since most of the pixel electrode 13 is formed on the interlayer insulating film 22, the pixel electrode 13 is not peeled off. However, considering the reliability of the electrical connection, the yield, etc., prior to the printing of the pixel electrode 13, plasma treatment such as oxygen plasma or ozone irradiation treatment is performed to remove the alkyl fluoride thiol 62 from the surface of the first electrode. It is desirable to keep it. The circuit board 1 having the organic TFT is manufactured through the above steps.

`` Penetration hole formation principle ''
FIG. 7 is a diagram for explaining the principle of the through-hole forming step in the circuit board manufacturing method according to the first embodiment. Here, the principle of through-hole formation will be described.
In order to open the through hole 32 in the gate insulating film 21 which is the first insulating film, a solvent droplet 52 is dropped on the first insulating film by an ink jet method. At this time, as shown in FIG. 7A, the solvent dropped onto the first insulating film spreads to a certain diameter depending on the wettability. The solvent evaporates while dissolving the underlying first insulating film. When the solvent evaporates, a micro flow toward the outer edge of the droplet 52 is generated as indicated by the arrow in FIG. This is because the contact line (outer edge) of the droplet 52 is pinned (fixed) and cannot be easily moved. As a result, the evaporation of the solvent in the vicinity of the contact line is compensated by the movement of the liquid from the center, and a micro flow from the center toward the outer edge portion is generated. The polymer (component of the first insulating film) dissolved in the solvent is also collected in the vicinity of the contact line along this minute flow. Thus, a crater-like through hole 32 as shown in FIG. 7C is formed.

  Based on the above principle, in order to open the through-hole 32 by this method, (1) the first insulating film is easily dissolved in the dropped solvent, and (2) the contact angle between the solvent and the first insulating film is 15 °. More than about, not so much wet and spread, (3) The drying speed of the solvent is slow, the first insulating film is dissolved in the solvent, and there is time to move it in a micro flow (that is, the boiling point of the solvent It can be understood that the four points are important: (4) the viscosity of the solvent is low to some extent and the liquid can move.

  According to experiments, butyl acetate and PGMEA, which have excellent solubility, are too low in viscosity, making it difficult to discharge the solution by a simple ink jet method (the drive waveform needs to be optimized). When the surface tension is approximately 40 mN / m, the contact angle with respect to PMMA is slightly less than 15 °, and the diameter of the outer peripheral edge (vertical portion raised in FIG. 7 (c)) and the diameter of 20 pL droplet 52 is approximately 100 μm. Through holes 32 could be formed by forming openings of 20 μm to 30 μm (bottom portions where the electrodes were exposed in FIG. 7C). Diclohexanol acetate exhibits excellent solubility, but since the boiling point is as low as 173 ° C., only about 10 nm can be dug by one drop. Accordingly, the boiling point is preferably about 180 ° C. or higher.

As described above, according to the circuit board manufacturing method of the present embodiment, the following effects can be obtained.
A through hole 32 is opened in the first insulating film on the first conductor by a printing method to expose the surface of the first conductor, and the surface of the first conductor is made liquid repellent. Since the precursor resin is printed in the region to form the second insulating film, the via hole 31 can be easily opened in the circuit board 1 by a printing method. In order not to adversely affect the electronic elements produced on the circuit board 1, the circuit board 1 exhibiting excellent circuit characteristics can be stably manufactured by a printing method with a high yield.

  Further, since the second conductor is formed on the first insulating film after the lyophobic process, only the portion where the through hole 32 is opened in the first conductor is selectively lyophobic, and the second conductor is Not repellent. Thus, in the next second insulating film forming step, the precursor resin can be printed uniformly on the second conductor, and the second conductor can be electrically insulated by the second insulating film.

  In addition, since the third conductor is formed in the region including the through hole 32 after the second insulating film forming step, electrical conduction can be established between the first conductor and the third conductor. The circuit board 1 having a complicated and highly functional circuit can be manufactured by a printing method.

  In addition, since the organic semiconductor film 41 is printed after the first conductor forming step and then the first insulating film forming step is performed, an organic thin film transistor can be formed on the circuit board 1. Furthermore, a high-performance thin film transistor can be manufactured with a high degree of freedom in the process of forming the first conductor. In addition, since the photolithography process and the etching process can be used prior to the formation of the organic semiconductor film 41 and the gate insulating film 21, the channel formation region length can be extremely shortened to several microns or less. It is possible to provide a thin film transistor circuit taking advantage of the scaling advantage on the circuit board 1.

  Further, since the organic semiconductor film 41 is hardly soluble in ether solvents, ketone solvents, ester solvents, and fluorine solvents, an ink containing an organic semiconductor is used. Ready. That is, the organic semiconductor can be printed in a shape required for the circuit board 1 by a printing method such as the inkjet method 51.

  Further, since the first insulating film is soluble in any of ether solvents, ketone solvents, ester solvents, and fluorine solvents, the first insulating film can be formed by a printing method. In addition, since the options for the first insulating film are wide, the function of the circuit board 1 can be maximized. Further, when the first insulating film is used as the gate insulating film 21 of the transistor, since the first insulating film material does not dissolve the organic semiconductor film 41, a thin film transistor having excellent characteristics is manufactured on the circuit board 1. Can do.

  In addition, since the first insulating film is hardly soluble in the alcohol solvent, the alcohol insulating material or the alcohol solvent is used in the lyophobic process, the second conductor forming process, and the second insulating film forming process. Since a soluble material can be used and the first insulating film is not damaged during these steps, the first insulating film can be maintained without deteriorating the function required for the circuit board 1.

  In addition, since the first insulating film is hardly soluble in the precursor resin, the first insulating film is not damaged by the precursor resin during the second insulating film forming step. The function required for the substrate 1 can be maintained without deteriorating.

  Further, in the through hole forming step, a solvent for dissolving the first insulating film is dropped onto the first insulating film, so that the fine through hole 32 can be easily formed by a printing method.

  In addition, the through hole forming step includes an etching step for uniformly etching the first insulating film, and the etching step is performed after the solvent dropping step. Can be formed.

  In the liquid repellency step, the surface of the first conductor is brought into contact with the solution 61 containing the thiol compound or disulfide compound, so that only the surface of the first conductor can be easily contacted in a short time of several seconds to several minutes. It can be selectively made liquid repellent.

  Further, since the thiol compound contains a fluorinated alkyl chain, the liquid repellency of the surface to which the thiol compound is bonded can be extremely increased.

  Moreover, since the disulfide compound contains a fluorinated alkyl chain, the liquid repellency of the surface to which the disulfide compound is bonded can be extremely increased.

  In addition, since the precursor resin contains a monomer having a hydroxyl group and the first insulating film is stable with respect to the alcohol-based material, the precursor resin can avoid damaging the first insulating film.

  Further, since the precursor resin is soluble in an alcohol solvent, the concentration of the solution can be adjusted relatively freely, and various printing methods can be applied to the second insulating film forming step. Furthermore, since the first insulating film is stable with respect to the alcohol-based material, it is possible to avoid the second insulating film forming step from damaging the first insulating film.

  Further, since the precursor resin is a photocurable resin, the second insulating film can be formed quickly and easily by irradiating light.

  Further, since the precursor resin is a thermosetting resin, the second insulating film can be easily formed by a simple heat treatment.

  Further, since the circuit board 1 includes a transistor including the gate insulating film 21, and the first insulating film functions as the gate insulating film 21, the circuit board 1 having a high-function circuit can be realized.

"Electro-optical device"
FIG. 8 is a plan view schematically showing an active matrix substrate manufactured using the circuit board manufacturing method described in detail in the first embodiment.

  Pixel circuits are arranged in a matrix on the active matrix substrate 81 to form a pixel region 71. Each pixel circuit is provided with an organic TFT 72 and a pixel electrode 13, and display information from the signal line 73 to the pixel electrode 13 is controlled by a switching operation of the organic TFT 72. Specifically, the gate electrode 12 of the organic TFT 72 is connected to the scanning line 74, one of the source / drain electrodes 11 is connected to the signal line 73, and the other of the source / drain electrodes 11 is connected to the pixel electrode 13. The plurality of scanning lines 74 are connected to the scanning line electrode pads 111 and connected to an external control circuit made of a silicon chip. Similarly, a plurality of signal lines 73 are also collected on the signal line electrode pads 111 and connected to an external control circuit made of a silicon chip.

  As shown in FIG. 3 (j), the source / drain electrode 11, the signal line 73, and the electrode pad 111 are formed of the first conductor, the gate insulating film 21 becomes the first insulating film, and the gate electrode 12 and the scanning line 74 are formed. Is formed of the second conductor, the interlayer insulating film 22 is the second insulating film, and the pixel electrode 13 is formed of the third conductor. The manufacturing method of the circuit board 1 described in detail in the first embodiment is applied to manufacture the active matrix substrate 81 having such a configuration.

  FIG. 9 is a cross-sectional view schematically showing an electro-optical device using the above-described active matrix substrate.

  The electro-optical device 80 includes an active matrix substrate 81 and a front substrate 82, and an electro-optical material is sandwiched between the substrates. The electro-optic material is an electrophoretic material 83, and therefore the electro-optic device 80 is an electrophoretic display. A common electrode 86 is formed on the surface of the front substrate 82. The electro-optic material is uniformly disposed on almost the entire surface of both substrates. The common electrode 86 is also formed on almost the entire surface of the front substrate 82. A flexible printed circuit (FPC 84) is connected to the electrode pad 111. A display signal from an external control circuit is supplied to each pixel electrode 13 via the FPC 84 and the organic TFT 72 of each pixel. A protective sheet 85 is attached to the outside of the active matrix substrate 81 and the front substrate 82 to enhance the mechanical durability and chemical stability of the electro-optical device 80.

  Since such an electro-optical device 80 includes the above-described active matrix substrate 81, the display quality is high. Furthermore, since the active matrix substrate 81 is manufactured by the above-described manufacturing method of the circuit board 1, the productivity is very high, and both resources and energy are utilized with high efficiency.

"Electronics"
FIG. 10 is a perspective view schematically showing an electronic apparatus using the above-described electro-optical device, where (a) is a front perspective view and (b) is a rear perspective view. Here, the electronic device is an electronic book 90.

  As illustrated in FIG. 10A, the electronic book 90 includes an electro-optical device 80 and a housing 91. The electro-optical device 80 has a flat rectangular shape. The casing 91 is disposed on the outer edge portion of the electro-optical device 80 and holds the electro-optical device 80. That is, the housing 91 is a holding unit for the display device. The holding part is gripped by the user's hand during use.

The electro-optical device 80 has a vertically long rectangle, and the casing 91 has a thin flat plate shape. As shown in FIG. 10A, a housing upper part 92 (an upper part of the housing 91) is provided on the front surface serving as the display surface, and on the back surface opposite to the display surface as shown in FIG. Is provided with a casing lower portion 93 (a lower part of the casing 91). The casing upper part 92 and the casing lower part 93 are both thin flat plates, and are overlapped to form a casing 91. As can be seen by comparing FIG. 10A and FIG. 10B, the front casing 91 width (width W _F ) is smaller than the rear casing 91 width (width W _B ). ing.

  Various circuits (control circuit) for controlling the electro-optical device 80, a power source, and the like are housed in the lower portion 93 of the housing, and as a result, the housing 91 is a major part of more than half of the weight of the electronic book 90. Occupies a proportion. For these reasons, the center of gravity of the electronic book 90 is located in the housing lower part 93.

  Various types of information are displayed on the display unit of the electro-optical device 80. An operation switch 94 is provided in the center of the casing 91, and information displayed on the display unit is updated through the switch operation.

  The electro-optical device 80 is light and flexible. For this reason, it is relatively strong against external impact, and it is not necessary to cover and protect the entire electro-optical device 80 with the casing 91. Thus, the housing 91 can be provided on the outer edge portion of the electro-optical device 80. Since the housing 91 does not cover the entire display device and there is no need to dispose a metal reinforcing member or the like, the entire electronic book 90 is made thin and light.

(Modification 1)
"TFT is the bottom gate type"
FIG. 11 is a cross-sectional view of a circuit board according to the first modification. Hereinafter, a circuit board and a manufacturing method thereof according to this modification will be described. In addition, about the component same as Embodiment 1, the same number is attached | subjected and the overlapping description is abbreviate | omitted. This modification (FIG. 11) differs from the first embodiment (FIG. 3 (j)) in the structure of the organic TFT. Other configurations are almost the same as those of the first embodiment.

  In the first embodiment, the gate electrode 12 of the TFT is positioned above the organic semiconductor film 41 (upper gate type). However, in the present modification, the gate electrode 12 of the TFT is the organic semiconductor film 41 as shown in FIG. It is located on the lower side (lower gate type). That is, the gate electrode 12, the gate insulating film 21, the source / drain electrode 11, the organic semiconductor film 41, the first interlayer insulating film 221, the second interlayer insulating film 222, and the pixel electrode 13 are stacked in this order from the substrate 10 side. Yes. Of these, the source / drain electrode 11 is the first conductor, the first interlayer insulating film 221 is the first insulating film, the second interlayer insulating film 222 is the second insulating film, and the pixel electrode 13 is the third conductor. .

  The manufacturing method of the circuit board 1 having the lower gate type organic TFT 72 is as follows. First, the gate electrode 12, the electrode pad 111, and the scanning line 74 (not shown) are formed on the substrate with the second conductor, and then the gate insulating film 21 is formed. The gate insulating film 21 is formed using a die coating method or the like so as not to cover a part of the electrode pad 111. Thereafter, a first conductor is formed on the gate insulating film 21 as a first conductor forming step. The first conductor becomes the source / drain electrode 11 and a signal line 73 (not shown). The organic semiconductor film 41 is printed immediately before or after the first conductor forming step. In this modification, printing is performed immediately after the first conductor forming step. Next, as a first insulating film forming step, a first interlayer insulating film 221 is formed so as to cover the first conductor. Next, as a through hole forming step, a through hole 32 is opened in the first interlayer insulating film 221 on the source / drain electrode 11 to expose the surface of the source / drain electrode 11. Next, as a liquid repellent step, the surface of the source / drain electrode 11 provided with the through hole 32 is made liquid repellent. Next, as a second insulating film forming step, a precursor resin is printed in a region other than the through holes 32, and the precursor resin is cured after printing to form the via holes 31 and the second interlayer insulating film 222. Finally, as a third conductor forming step, the pixel electrode 13 is printed in a region including the via hole 31. Each process from the first conductor forming process to the third conductor forming process is performed as described in the first embodiment.

As described above, according to the method of manufacturing the circuit board 1 according to this modification, the following effects can be obtained in addition to the effects of the first embodiment.
The first interlayer insulating film 221 of this modification is a first insulating film, and the first insulating film is the gate insulating film 21 in the first embodiment. That is, the first interlayer insulating film 221 of this modification has a film quality equivalent to that of the gate insulating film 21, and therefore the interface with the semiconductor film is also made high quality. The electrical characteristics of the TFT are strongly influenced by the interface of the semiconductor film on the gate electrode 12 side, and the interface on the opposite side (back side interface) also affects the electrical characteristics. In this modification, the interface on the back side of the semiconductor is covered with a high-quality polymer film that can also be used for the gate insulating film 21. Therefore, the number of interface traps generated at the interface on the back side is suppressed, and a high-performance organic TFT 72 is obtained. Further, since the first interlayer insulating film 221 and the second interlayer insulating film 222 are provided between the signal line 73 and the pixel electrode 13, the parasitic capacitance between them is reduced and the leakage current is also reduced. The circuit will operate fast and accurately.

  In general, when a reactive monomer or curing agent is in direct contact with an organic semiconductor material, the semiconductor characteristics are deteriorated. Therefore, if the UV ink 54 is applied directly on the organic semiconductor film 41, the organic TFT is forced to deteriorate the semiconductor characteristics. However, in the present modification, the high-quality first interlayer insulating film 221 protects the organic semiconductor film 41, and the UV ink 54 does not contact the organic semiconductor film 41. For this reason, the organic TFT exhibits excellent semiconductor characteristics. As a result, the first interlayer insulating film 221 is a protective film for the organic semiconductor film 41 and simultaneously plays a role of selectively forming the second interlayer insulating film 222 in a region other than the via hole 31.

(Modification 2)
“Example in which the active matrix substrate 81 includes capacitance lines”
FIG. 12 is a plan view of the circuit board manufacturing method according to the second modification. Hereinafter, the circuit board 1 according to this modification and the manufacturing method thereof will be described. This modification (FIG. 12) is different from the first embodiment (FIG. 4B) in that a capacitor electrode is provided on the circuit board 1. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.

  In this modification, a storage capacitor is formed in the pixel circuit. The storage capacitor includes a first capacitor electrode, a second capacitor electrode 121, and a dielectric film sandwiched between these electrodes. The first capacitor electrode is connected to a pixel electrode (not shown), and the second capacitor electrode 121 is connected to a reference potential such as a ground potential or a common electrode potential. In the circuit board 1, a source / drain electrode 11 is formed of a first conductor, one of which is connected to the signal line 73 and the other is connected to a pixel electrode (not shown), but the first capacitor electrode is the other source. Also used as the drain electrode 11. The dielectric film is the same first insulating film as the gate insulating film. The second capacitor electrode 121 is formed of the same second conductor as the gate electrode 12 as shown in FIG. In order to connect the second capacitor electrode 121 to the reference potential, the capacitor common line 112 and a plurality of capacitor electrodes are connected. The capacitor common line 112 is formed of a first conductor, and is connected to the second capacitor electrode 121 through the through hole 32 provided in the capacitor common line 112. Therefore, the electrode surface of the through hole 32 is hydrophilic. The circuit board 1 having such a configuration is manufactured by the manufacturing method described in detail in the first embodiment.

  When the pixel circuit has a storage capacitor in the electrophoretic display, a voltage is applied to the electrophoretic material throughout the frame period, so that a high-contrast image can be easily displayed.

(Modification 3)
“Example of drive circuit partially built in TFT”
FIG. 13 is a plan view of a circuit board according to the third modification. FIG. 14 is a cross-sectional view of a circuit board according to the third modification. Hereinafter, the circuit board 1 according to this modification and the manufacturing method thereof will be described. This modification (FIG. 13) differs from the active matrix substrate 81 (FIG. 8) described in the first embodiment in that a part of the drive circuit is built in the TFT. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.

  In this modified example, as shown in FIG. 13, the organic TFT 72 constitutes a scanning circuit 75 that is a part of the drive circuit. The scanning circuit 75 includes a shift register and can select the scanning line 74. A series connection of inverters is used in the shift register, and FIG. 14 schematically shows a cross section of the portion. That is, the drain electrode 114 of the first organic TFT 721 becomes an output, and this is connected as an input to the gate electrode 12 of the second organic TFT 722. The circuit board 1 having such a configuration is manufactured by the manufacturing method described in detail in the first embodiment. Note that the electrode surface of the through hole 32 provided in the drain electrode 114 of the first organic TFT 721 is made hydrophilic.

  Since the drive circuit of the active matrix substrate 81 is partially built in, the electro-optical device 80 that displays a high-definition image can be obtained.

(Modification 4)
“Example of thin glass substrate”
This will be described with reference to FIG.
This modification differs from Embodiment 1 in that the substrate is thin glass. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.

  In the first embodiment, the substrate 10 is a plastic film, but the substrate 10 is not limited to this. For example, after the process described in detail in Embodiment 1 is performed on the surface of the glass substrate having a thickness of 0.5 mm to 1.1 mm, the back surface of the glass substrate may be etched to reduce the thickness to 0.1 mm or less. When the thickness of the glass substrate is 0.1 mm or less, flexibility is exhibited.

  In this way, a glass substrate having a normal thickness of 0.5 mm to 1.1 mm can be used when the circuit board 1 is manufactured, and then the flexible circuit board 1 can be relatively easily obtained simply by thinning the glass. Can be manufactured.

(Modification 5)
"Example where the substrate is a thin metal plate"
This will be described with reference to FIG.
This modification differs from Embodiment 1 in that the substrate is a thin metal plate. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.

  In the first embodiment, the substrate 10 is a plastic film, but the substrate 10 is not limited to this. For example, a thin stainless steel substrate may be covered with an inorganic insulating film such as a silicon oxide film or a nitrogen oxide film, or an organic insulating film such as polyimide, and used as the substrate 10. When a metal plate is used as the substrate 10, the substrate potential can be freely set, and the threshold voltage Vth of the organic TFT 72 can be easily adjusted. The surface of the organic insulating film is easily charged during manufacture. Therefore, if the charge removal on the insulating film surface is not performed properly, the Vth of the organic TFT 72 will deviate from the design value. In this modification, the organic TFT 72 can be operated correctly by adjusting the substrate potential even if the Vth shifts.

(Modification 6)
“Examples of electro-optic materials other than electrophoretic materials”
This will be described with reference to FIG.
This modification differs from Embodiment 1 in that a liquid crystal material or the like is used instead of the electrophoretic material 83 as an electro-optic material. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.

  In the first embodiment, the electrophoretic material 83 is used as the electro-optic material. However, as the electro-optic material, a liquid crystal material, an organic or inorganic electroluminescence (EL) material, an electrochromic material, or the like is also used. You may do it. Accordingly, the electro-optical device 80 is a liquid crystal display (LCD), an organic or inorganic electroluminescence display (also called a light emitting diode display, LED display), an electrochromic display (ECD). Etc. Examples of the electronic apparatus having the electro-optical device 80 include an electronic book, a television, a mobile phone, and a personal computer.

(Modification 7)
“Example of common electrode made on the first substrate”
This will be described with reference to FIG.
Modification 7 is different from Embodiment 1 (FIG. 9) in that the common electrode 86 is formed on the first substrate side. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.
In the first embodiment (FIG. 9), the common electrode 86 is formed on the front substrate 82, but this is not essential, and the common electrode 86 may be formed on the active matrix substrate 81. In this case, the common electrode 86 is provided in each pixel of the active matrix substrate 81, and a so-called in-plane switch type electro-optical device in which an electric field having an electric field component parallel to the surface of the active matrix substrate 81 is applied to the electro-optical material. 80. Applicable to EPDs and wide viewing angle liquid crystal displays that perform lateral electrophoresis.

(Modification 8)
"Example of multilayer wiring board"
FIG. 15 is a cross-sectional view of a circuit board according to Modification 8.
The modification 8 differs from the first embodiment (FIG. 3 (j)) in that the circuit board is a multilayer wiring board. The rest of the configuration is almost the same as in the first embodiment, and a duplicate description is omitted.
In Embodiment 1 (FIG. 3 (j)), the organic TFT is provided on the circuit board, but this is not essential, and the circuit board may be a multilayer wiring board.

  As shown in FIG. 15, the multilayer wiring substrate 100 is laminated in the order of the first wiring 113, the first interlayer insulating film 221, the second interlayer insulating film 222, and the second wiring 131 from the substrate side. Among these, the first wiring 113 is the first conductor, the first interlayer insulating film 221 is the first insulating film, the second interlayer insulating film 222 is the second insulating film, and the second wiring 131 is the third conductor. It hits.

  A method of manufacturing the circuit board 1 having such multilayer wiring is as follows. First, the first wiring 113 is formed on the substrate as a first conductor forming step. Next, as a first insulating film forming step, a first interlayer insulating film 221 is formed so as to cover the first conductor. Next, as a through hole forming step, the through hole 32 is opened in the first interlayer insulating film 221 of the first wiring 113 to expose the surface of the first wiring 113. Next, as a liquid repellent step, the surface of the first wiring 113 provided with the through holes 32 is made liquid repellent. Next, as a second insulating film forming step, a precursor resin is printed in a region other than the through hole 32, and the precursor resin is cured after printing to form the second interlayer insulating film 222 and the via hole 31. Next, as a third conductor forming step, metal ink is printed in a region including the via hole 31 to form the second wiring 131. Prior to printing the metal ink, the fluorinated alkyl thiol 62 (not shown) is removed from the bottom surface of the via hole 31. Thus, each process from the first conductor forming process to the third conductor forming process is performed by the method described in the first embodiment, and a two-layer wiring board is completed.

  One cycle for producing the multilayer wiring is from the first insulating film forming step to the third conductor forming step, and the above-mentioned third conductor is used as the first conductor in the next cycle. Can be repeated a plurality of times to obtain a multilayer wiring board 100 having a large number of wiring layers.

  In the above description, the names of the first conductor, the second conductor, and the third conductor are used for the three types of conductors. It is a name and does not specify the order of formation. Furthermore, three types of conductors are not required in the circuit board 1. For example, the circuit board 1 is provided with a first conductor, a first insulating film covering the first conductor, and a second insulating film as a protective film for the first conductor. The present invention can also be applied to a circuit board 1 having only one type of conductor, such as a structure having a via hole 31 for contacting a needle.

  DESCRIPTION OF SYMBOLS 1 ... Circuit board, 10 ... Board | substrate, 11 ... Source-drain electrode, 12 ... Gate electrode, 13 ... Pixel electrode, 21 ... Gate insulating film, 22 ... Interlayer insulating film, 31 ... Via hole, 32 ... Through-hole, 41 ... Organic Semiconductor film 51 ... Inkjet method 52 ... Droplet 53 ... Conductor ink 54 ... UV ink 55 ... Ultraviolet light 61 ... Solution 62 ... Alkyl thiol 72 ... Organic TFT 80 ... Electro-optical device , 81 ... Active matrix substrate, 90 ... Electronic book, 100 ... Multi-layer wiring substrate, 111 ... Electrode pad, 113 ... First wiring, 131 ... Second wiring, 221 ... First interlayer insulating film, 222 ... Second interlayer insulating film.

Claims (18)

A first conductor forming step of forming a first conductor on the substrate;
A first insulating film forming step of forming a first insulating film so as to cover the first conductor;
A through hole forming step of opening a through hole in the first insulating film on the first conductor to expose a surface of the first conductor;
A liquid repellency step for making the surface of the first conductor liquid repellant;
A second insulating film forming step of printing a precursor resin in a region other than the through-hole, and curing the precursor resin after printing to form a second insulating film;
A method for manufacturing a circuit board, comprising: After the liquid repellency step, including a second conductor forming step of forming a second conductor on the first insulating film,
The method for manufacturing a circuit board according to claim 1, wherein the second insulating film forming step is performed after the second conductor forming step.   The method for manufacturing a circuit board according to claim 1, further comprising a third conductor forming step of forming a third conductor in a region including the through hole after the second insulating film forming step. After the first conductor forming step, including a semiconductor film forming step of printing an organic semiconductor film,
The method for manufacturing a circuit board according to claim 1, wherein the first insulating film forming step is performed after the semiconductor film forming step.   5. The organic semiconductor film according to claim 4, wherein the organic semiconductor film exhibits poor solubility in an ether solvent, a ketone solvent, an ester solvent, and a fluorine solvent. Circuit board manufacturing method.   The circuit board according to claim 1, wherein the first insulating film is soluble in any of an ether solvent, a ketone solvent, an ester solvent, and a fluorine solvent. Manufacturing method.   The method of manufacturing a circuit board according to claim 1, wherein the first insulating film is hardly soluble in an alcohol solvent.   The method of manufacturing a circuit board according to claim 1, wherein the first insulating film is hardly soluble in the precursor resin.   The circuit board according to claim 1, wherein the through-hole forming step includes a solvent dropping step of dropping a solvent that dissolves the first insulating film onto the first insulating film. Manufacturing method. The through hole forming step includes an etching step for uniformly etching the first insulating film,
The method for manufacturing a circuit board according to claim 9, wherein the etching step is performed after the solvent dropping step.   The method for manufacturing a circuit board according to claim 1, wherein the liquid repellency step includes bringing a surface of the first conductor into contact with a solution containing a thiol compound or a disulfide compound.   The method for producing a circuit board according to claim 11, wherein the thiol compound includes a fluorinated alkyl chain.   The method for manufacturing a circuit board according to claim 11, wherein the disulfide compound includes a fluorinated alkyl chain.   The method for manufacturing a circuit board according to claim 1, wherein the precursor resin contains a monomer having a hydroxyl group.   The method for manufacturing a circuit board according to claim 1, wherein the precursor resin is soluble in an alcohol-based solvent.   The method for manufacturing a circuit board according to claim 1, wherein the precursor resin is a photocurable resin.   The method for manufacturing a circuit board according to claim 1, wherein the precursor resin is a thermosetting resin. The circuit board includes a transistor including a gate insulating film,
The method for manufacturing a circuit board according to claim 1, wherein the first insulating film functions as the gate insulating film.

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