JP2020004648A - Method for manufacturing conductive pattern, and plasma treatment apparatus - Google Patents

Abstract

To provide, in particular, by performing plasma treatment in a state where oxygen is present, a method for manufacturing conductive pattern that can achieve shortening of the treatment time and lowering of the resistance, and to provide a plasma treatment apparatus.SOLUTION: The method for manufacturing conductive pattern according to the present invention comprises containing an object to be treated having a pattern formed on a substrate using an ink in which copper oxide is dispersed, in a pressure reduced chamber, and performing plasma treatment in a state in which oxygen is present.SELECTED DRAWING: None

Description

  The present invention relates to a method for manufacturing a conductive pattern and a plasma processing apparatus.

  As a method of forming a conductive pattern on a substrate, for example, an ink in which metal oxide particles are dispersed is drawn on a substrate by printing or coating to form a pattern, and the pattern is formed in a reducing atmosphere. There is known a method of forming a conductive pattern by heating under reduced pressure and sintering.

  However, this method requires a high processing temperature and is difficult to apply to a substrate material having low heat resistance such as PET or PEN. Further, the processing time is as long as tens of minutes.

  On the other hand, the method using plasma treatment can be applied to a substrate having relatively low heat resistance, such as PET or PEN, and can form a conductive pattern within several minutes (see Patent Document 1). .

Japanese Patent No. 6072709

  However, in order to respond to mass production, it is required to further reduce the processing time without increasing the resistance value.

  One of the factors that require time for the treatment is that it takes time to decompose and remove organic compounds such as dispersants and surfactants that are added when the conductive raw material is converted into ink.

  Therefore, the present invention has been made to solve the above-mentioned conventional problems, and in particular, provides a method of manufacturing a conductive pattern and a plasma processing apparatus capable of reducing processing time and reducing resistance. The purpose is to:

  In the method for producing a conductive pattern according to the present invention, an object to be processed in which a pattern is formed on a substrate using an ink in which copper oxide is dispersed is housed in a decompressed chamber, and plasma treatment is performed in the presence of oxygen. Is performed.

  In the present invention, it is preferable that the plasma processing is performed in a state where hydrogen gas is present in the chamber.

  Further, in the present invention, it is preferable that the oxygen is supplied into the chamber from outside.

  In the present invention, it is preferable that the copper oxide contains at least cuprous oxide.

  In the present invention, it is preferable that the object to be treated contains the cuprous oxide and an organic compound having a phosphate group.

  In addition, the plasma processing apparatus according to the present invention includes a chamber capable of accommodating an object to be processed in which a pattern is formed on a substrate using ink in which copper oxide is dispersed, and a plasma generation unit that generates plasma in the chamber. Oxygen supply means capable of supplying oxygen into the chamber, wherein the object is subjected to plasma processing in a state where the oxygen is supplied by the oxygen supply means into the chamber under reduced pressure. It is characterized by the following.

  According to the present invention, by performing the plasma processing in a state where oxygen is present, it is possible to reduce the processing time and reduce the resistance.

It is a flowchart which shows the manufacturing process of the conductive pattern of this embodiment. It is a schematic diagram of the plasma processing apparatus of the present embodiment. It is a figure showing the relationship between oxygen concentration and specific resistance of a present Example.

  Hereinafter, one embodiment of the present invention (hereinafter, abbreviated as “embodiment”) will be described in detail. The present invention is not limited to the following embodiments, and can be implemented with various modifications within the scope of the gist.

[Manufacturing process of conductive pattern]
FIG. 1 is a flowchart showing a process for manufacturing the conductive pattern of the present embodiment. First, as shown in FIG. 1, ink is generated (step ST1). In the present embodiment, an ink in which copper oxide is dispersed in a dispersion medium is generated. As an example, an ink containing fine particles of cuprous oxide and an organic compound having a phosphate group is generated.

  Subsequently, a pattern is formed by printing or applying ink on the substrate (step ST2). In the present embodiment, the pattern forming method is not limited, for example, screen printing, intaglio direct printing, intaglio offset printing, flexographic printing, lithographic offset printing, reverse transfer printing, and printing methods such as inkjet printing, dispenser A drawing method can be used. Various coating methods such as die coating, spin coating, slit coating, bar coating, knife coating, spray coating, and dip coating can be used as the coating method.

  Subsequently, the pattern formed on the substrate is dried (step ST3). By this step, the dispersion medium in the pattern can be removed. Although the drying method is not limited, a generally known drying method can be used. For example, the solvent can be dried using a hot air heating oven, an infrared heating furnace, a hot plate, and a vacuum dryer.

  Subsequently, the substrate with a pattern (object to be processed) is housed in the chamber 2 of the plasma processing apparatus 1 (step ST4).

  FIG. 2 is a schematic diagram of the plasma processing apparatus 1 of the present embodiment. As shown in FIG. 2, the plasma processing apparatus 1 includes a chamber 2, a stage 3 disposed in the chamber 2, a dielectric 13 disposed at a position facing the stage 3, and a window member 4 made of metal. A microwave generator 5 for generating microwaves; a waveguide 6 between the microwave generator (magnetron) 5 and the window member 4; and a gas supply port 8 for supplying gas into the chamber 2. , An exhaust port 9, and an internal pressure adjusting valve 14. The object 7 is placed on the surface of the stage 3.

  After the object 7 is accommodated in the chamber 2, plasma processing is performed (step ST5). The plasma processing used in the present embodiment can be performed at a lower temperature and in a shorter time than the heating method using hot air or infrared rays. Therefore, as a firing method when a resin film having low heat resistance is used as a substrate, a plasma processing method is one of more preferable methods.

  In FIG. 2, the microwave output from the microwave generator 5 reaches the window member 4 via the waveguide 6 via the isolator, the power monitor, and the tuner. The window member 4 has a slit 12. For example, the dielectric 13 is quartz. Microwaves of, for example, 2455 MHz ± 20 MHz are radiated from the slits 12 of the window member 4 into the chamber 2, which is reduced in pressure by the exhaust from the exhaust port 9, to generate surface wave plasma. The workpiece 7 is set on the stage 3 and processed. The stage 3 may have a function for heating or cooling the sample as needed. Note that the method of generating plasma is not limited to the above. For example, a plasma may be generated between the electrodes by disposing opposed electrodes in the chamber 2 and connecting a high-frequency power supply between the electrodes. At this time, the object 7 is placed on the surface of one of the electrodes and subjected to plasma processing.

  In addition, during the plasma treatment, a reducing gas or a mixed gas of a reducing gas and an inert gas is flowed into the chamber 2 from the gas supply port 8 to generate plasma by microwaves. Thereby, the reduction reaction of the object 7 in the chamber 2 is promoted. Further, the organic substance contained in the dispersant, the surfactant, and the like added to the ink is appropriately decomposed and removed, and a conductive pattern having excellent conductivity can be obtained (step ST6).

  In order to make the particles in the oxidized state a conductive pattern, as a reducing gas, in addition to hydrogen, carbon monoxide, ammonia, methane, ethane, propane, butane, hydrocarbon-based gas such as acetylene, methanol, ethanol, Alcohols such as propanol and butanol, ethers such as dimethyl ether, diethyl ether, ethyl methyl ether, ethylene oxide, oxetane, and tetrahydrofuran; glycols such as ethylene glycol, diethylene glycol and propylene glycol; formaldehyde, acetaldehyde, and propionaldehyde Aldehydes, formic acid and the like can be mentioned, and one of these may be used, or two or more may be used in combination.

  Helium gas having an effect of facilitating generation of plasma can be preferably used as the inert gas. Note that other than helium gas, neon gas, argon gas, krypton gas, xenon gas, nitrogen gas, or the like may be used. Further, two or more kinds of inert gases may be used as a mixture.

  Further, at the time of the plasma treatment, water that is effective in shortening the treatment time and reducing the resistance may be supplied. Water can be supplied, for example, by a method in which water is mixed with one or both of an inert gas and a reducing gas and supplied to the chamber 2. Further, it can also be performed by a method in which water is adsorbed on the substrate of the processing object 7 or a material in which the water is adsorbed is charged into the chamber 2.

  In the plasma processing apparatus 1, it is possible to adjust microwave input power, introduced gas flow rate, chamber internal pressure, distance from a plasma generation source to a processing sample, processing sample temperature, processing time, and the like. By appropriately adjusting these, the intensity of the plasma treatment can be changed. Therefore, by optimizing each of the above adjustment items, not only when a substrate made of an inorganic material is used as the substrate, but also as a thermosetting resin film of an organic material, paper, or a thermoplastic resin film having low heat resistance. For example, even when PET, PEN, or the like is used as a substrate, a conductive pattern can be formed.

  However, the optimal conditions for the plasma processing vary depending on the structure of the plasma processing apparatus 1, the composition of the ink, the thickness of the pattern, the material of the substrate, and the like. Therefore, it is necessary to adjust the optimum conditions of the plasma processing according to various situations. Further, a batch system in which the workpiece 7 is charged into the chamber 2 every time it is fired and taken out, or a system in which the workpiece 7 is continuously supplied by a roll may be used. Further, a mechanism capable of heating or cooling the processing target 7 may be provided. Regarding the heating temperature of the processing target 7, usually, when performing plasma processing, the higher the temperature, the easier the sintering proceeds. Therefore, a method of heating and processing the processing target 7 is known. However, if the temperature is too high, the substrate is deformed or melted. Therefore, it is preferable to set the temperature to be equal to or lower than the heat resistant temperature of the substrate. In the present embodiment, since the sintering ability is high, sufficient sintering is possible without heating the object to be processed 7 even when the temperature is set to around room temperature or lower. In particular, when the heat-resistant temperature of the substrate is low, the temperature may be set to room temperature or lower. The upper limit of the heating temperature of the processing target 7 is preferably equal to or lower than the heat resistant temperature of the substrate, and the lower limit may be determined by the resistance value after the processing.

  After forming the conductive pattern, the processing target 7 is taken out of the chamber 2 (step ST7).

  By the way, conventionally, it took time for the plasma processing. The ink has a dispersant added to prevent aggregation of the dispersion of fine particles, a surfactant and a leveling agent added to prevent defects such as cissing, and good coating and printability for pattern formation. Various additives such as a binder for thickening, a fluidity regulator, an adhesion-imparting agent for imparting adhesion, and a stabilizer are added for the purpose of reducing the viscosity.

  In order to properly promote the sintering of the fine particles, the additives must be appropriately decomposed and removed. However, adding various types of additives requires time for decomposition and removal. This is considered as one of the causes of the time required for the plasma processing.

  Thus, as a result of diligent research, the present inventor has found that by performing the plasma treatment in the presence of oxygen, the effects of shortening the treatment time and decreasing the resistance value can be obtained.

  It is not clear why this effect is obtained, but by performing the plasma treatment in the presence of oxygen, oxygen is decomposed, and oxygen radicals and excited oxygen are generated.

  These react with organic substances such as a dispersant, a surfactant and a thickener present in the pattern. As a result, organic substances are promptly removed by oxidative decomposition, and as a result, sintering is facilitated. On the other hand, hydrogen gas used as a reducing gas generates hydrogen radicals by performing a plasma treatment and contributes to reduction of metal oxides. It is presumed that the processing time and the resistance value can be reduced by the above mechanism.

  Further, when oxygen radicals and excited oxygen react with an organic substance, they eventually become carbon dioxide and water. However, carbon dioxide generated by the reaction has a large bond dissociation energy and is hardly reduced. For this reason, oxygen radicals and excited oxygen are preferentially consumed, and hydrogen radicals generated by the decomposition of hydrogen effectively contribute to the reduction of copper oxide. It is also assumed that, in addition to the organic components contained in the ink, the resin substrate also functions to consume similar oxygen radicals and excited oxygen. Further, a material that consumes oxygen, such as a resin, an organic material, and carbon, other than the resin substrate actually used for pattern formation may be housed in the chamber 2 for processing.

  In addition, by supplying oxygen, it is considered that oxygen and hydrogen react with each other, hydrogen is consumed, and the reducing ability is reduced. It is presumed that the reduction ability hardly decreases due to the contribution.

  The amount of oxygen in the chamber 2 is 1.7% to 95%, preferably 8% to 90%, more preferably 13% to 80%, and still more preferably the amount of hydrogen gas supplied into the chamber 2 at the same time. Is preferably 27% to 70%, even more preferably 30% to 60%.

[How to supply oxygen]
Next, a method of supplying oxygen to the plasma processing apparatus 1 will be described. Oxygen may be supplied from the outside into the chamber 2 by controlling the flow rate of an oxygen gas alone or a mixed gas with air, an inert gas or the like so as to have a predetermined concentration.

  When oxygen is supplied into the chamber 2 from the outside, for example, oxygen or air containing oxygen is mixed with an inert gas or a reducing gas outside the chamber 2 and supplied through the gas supply port 8 shown in FIG. can do. Further, as shown in FIG. 2, an oxygen supply port 10 for newly supplying oxygen or air containing oxygen may be provided, and oxygen or air may be supplied into the chamber 2 from the oxygen supply port 10.

  As described above, when oxygen is contained in the gas, when one of the inert gas and the reducing gas, or both gases are mixed with oxygen and supplied into the chamber 2, the gas is mixed depending on the mixing ratio. The ratio of oxygen contained therein can be controlled.

  In the method of supplying oxygen from the oxygen supply port 10 to the chamber 2 shown in FIG. 2, for example, the flow rate is monitored to control the amount of oxygen. As a method of controlling the flow rate, a method of manually adjusting the adjustment valve 11 (see FIG. 2) such as a needle valve can be used.

  Further, the flow rates of these gases can be easily controlled by a known method such as using a mass flow controller.

  Further, the supply timing of oxygen (Step ST8) after the workpiece 7 is accommodated in the plasma processing apparatus 1 is such that the plasma is supplied between the step of accommodating the workpiece 7 in the chamber 2 and the plasma processing step. During the processing step or the like can be selected, and the supply timing and time may be arbitrarily changed during the plasma processing. For example, supply may be performed during plasma processing, or may be supplied at an arbitrary timing and time during processing, or supply and stop may be repeated during processing.

[Effects of the present embodiment]
As described above, in the present embodiment, by performing the plasma processing in a state where oxygen is present, the processing time of the plasma processing can be reduced and the resistance of the conductive pattern can be reduced.

  The plasma processing time is about 15 to 240 seconds, and the resistance value of the conductive pattern can be about 50 to 90 μΩcm. Further, as compared with the conventional example in which the plasma processing was performed in the absence of oxygen, the processing time of the plasma processing was the same in the present embodiment and the comparative example, and the resistance value of the conductive pattern of the comparative example was set to 1. At this time, the resistance value of the conductive pattern of the present embodiment can be reduced to about 0.2 to 0.5. Further, when the resistance value of the conductive pattern is the same in the present embodiment and the comparative example, and the processing time of the plasma processing of the comparative example is 1, the plasma processing time of the present embodiment is 0.2 to 0. It can be shortened to about 5.

  In the present embodiment, an ink in which copper oxide is dispersed can be used. Hereinafter, the ink used will be described in detail.

[Ink used]
Copper oxide contained in the ink is easily reduced among metal oxides, and fine particles can be obtained, and sintering is easy. Furthermore, copper oxide is inexpensive compared to noble metals such as silver because copper is also copper in price. Further, it has a feature that it is more advantageous for migration than silver.

  As copper oxide, cuprous oxide and cupric oxide are available, but cuprous oxide is preferred because it is easily reduced.

  The preferred range of the average primary particle diameter of the copper oxide particles is as follows: the compactness of the metal obtained by reducing the copper oxide, and the viewpoint of the electrical characteristics, and lowering the temperature to reduce the damage to the substrate during firing. It is adjusted from the viewpoint of. Specifically, the preferred range of the average primary particle diameter is 100 nm or less, more preferably 50 nm or less, and still more preferably 20 nm or less, as determined by the cumulant method.

  By setting the primary particle diameter of the copper oxide particles to 100 nm or less, the input energy in the baking treatment tends to be reduced, and damage to the substrate can be avoided. The lower limit of the average particle size of the copper oxide particles is not particularly limited, but is preferably 1 nm or more from the viewpoint of easy handling. If it is smaller than this, the amount of the dispersant used to maintain the dispersion stability increases, and the dispersant component to be removed during the baking treatment increases. As a result, it becomes difficult to appropriately remove the dispersant.

  The copper oxide particles dispersed in the ink are easily reduced to a metal (conductor) by the plasma treatment. Then, by sintering the metal particles (copper particles), it becomes possible to obtain conductivity.

  Note that in this embodiment, it is preferable to include copper oxide. However, as another example, a structure using at least silver oxide can be used. For example, silver oxide can be used in combination with copper oxide.

[Cuprous oxide]
Next, cuprous oxide will be described. Regarding cuprous oxide particles, a commercially available product may be used, or a synthesized product may be used. As a commercially available product, one having a primary particle size of 5 to 50 nm manufactured by Rare Metal Materials Laboratory Co., Ltd. can be used.

Further, examples of the synthesis method include the following method.
(1) Water and a copper acetylacetonato complex are added to a polyol solvent. Subsequently, the organic copper compound is once dissolved by heating, and then water required for the reaction is added later. Further, heat reduction is performed by raising the temperature and heating at the reduction temperature of the organic copper.
(2) The organic copper compound (copper-N-nitrosophenylhydroxyamine complex) is heated at a high temperature of about 300 ° C. in the presence of a protective agent such as hexadecylamine and in an inert atmosphere.
(3) The copper salt dissolved in the aqueous solution is reduced with hydrazine.

  Of the above, the method (3) is preferable because the operation is simple and cuprous oxide having a small particle size can be obtained.

[Preparation of cuprous oxide dispersion]
For example, as described in the above (3), a copper salt dissolved in an aqueous solution is reduced with hydrazine to synthesize cuprous oxide. The obtained cuprous oxide is a soft aggregate. Since this state is not suitable for printing or coating, a dispersion of cuprous oxide dispersed in a dispersion medium is prepared.

  First, after the synthesis of cuprous oxide is completed, the synthesis solution and cuprous oxide are separated. At this time, separation can be performed using a known method such as centrifugation. The obtained cuprous oxide is added with a dispersant, a dispersion medium, and, if necessary, a surfactant, which will be described later, and stirred and dispersed by a known method such as a homogenizer.

  Note that, depending on the dispersion medium, dispersion is difficult and dispersion may be insufficient. In such a case, as an example, an easily dispersible alcohol such as butanol is used for dispersion. Thereafter, replacement with a desired dispersion medium and concentration to a desired concentration are performed. For example, a dispersion can be obtained by a method of repeating concentration with a UF membrane, dilution with a desired dispersion medium, and concentration.

[Dispersant]
Although a dispersant is not limited in the present embodiment, when copper (I) oxide is used as copper oxide, it is preferable to use an organic compound having a phosphate group as the dispersant. The phosphate groups are adsorbed on the copper oxide particles and suppress aggregation due to a steric hindrance effect.

  The number average molecular weight of the dispersant is not particularly limited, but is preferably 300 to 30,000. When the number average molecular weight is 300 or more, the dispersion stability of the obtained dispersion tends to increase. Further, by setting the number average molecular weight to 30,000 or less, there is an effect that firing is easy.

  Specific examples of the dispersant include “Disperbyk-102”, “Disperbyk-103”, “Disperbyk-110”, “Disperbyk-111”, “Disperbyk-118”, “Disperbyk-142”, and “Disperbyk” manufactured by BYK Chemie. -145 "," Disperbyk-180 "," Byk-9076 "," Plasurf M208F "and" Plysurf DBS "manufactured by Daiichi Kogyo Seiyaku. These may be used alone or in combination of two or more. The required amount of the dispersant is proportional to the amount of copper oxide and is adjusted in consideration of the required dispersion stability.

  The weight ratio of the organic compound having a phosphate group and copper oxide contained in the dispersion of the present embodiment is 0.001 to 0.35 when copper oxide is 1, and preferably 0.02 to 0. 0.3, more preferably 0.01 to 0.25. The amount of the dispersant affects the dispersion stability. When the amount of the dispersant is small, aggregation tends to occur, and when the amount of the dispersant is large, the dispersion stability tends to be improved. However, when the content of the dispersant exceeds 35.0% by weight, the residue derived from the dispersant increases in the conductor obtained by firing, and the conductivity tends to deteriorate.

  If a longer period of dispersion stability is required, the mixing ratio may be adjusted in a direction to increase the dispersing agent, and in a shorter period to decrease the mixing ratio.

[Additive]
During pattern formation, surfactants and leveling materials added to prevent defects such as cissing due to improved wettability to the substrate, and thickeners added to improve coating and printability for pattern formation If necessary, various kinds of additives such as a binder, a fluidity adjusting agent, an adhesive, and a stabilizer may be added.

[Metal particles]
Metal particles may be added to improve the strength of the conductive pattern, to increase the viscosity for improving the conductivity or the printability, and as the type of metal, gold, silver, copper, nickel, tin, zinc, etc. One or more particles can be added. The particle shape may be spherical, scaly, needle-like, dendritic, or other polyhedral.

[Dispersion medium]
As the dispersion medium used in the present embodiment, from the viewpoint of dispersion, a dispersible one is selected from those capable of dissolving the organic compound having a phosphate group of the dispersant. On the other hand, from the viewpoint of forming a pattern using a dispersion, since the volatility of the dispersion medium affects the workability, it must be suitable for a pattern forming method, for example, a printing or coating method. Accordingly, the dispersion medium may be selected from the following solvents according to the dispersibility and the workability of printing and coating.

  The following materials can be given as specific examples. That is, propylene glycol monomethyl ether acetate, 3-methoxy-3-methyl-butyl acetate, ethoxyethyl propionate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol tertiary butyl ether, dipropylene Glycol monomethyl ether, ethylene glycol butyl ether, ethylene glycol ethyl ether, ethylene glycol methyl ether, ethylene glycol, 1,2-propylene glycol, 1,3-butylene glycol, 2-pentanediol, 2-methylpentane-2,4-diol , 2,5-hexanediol, 2,4-heptanediol, 2-ethylhexane-1,3- All, diethylene glycol, hexanediol, octanediol, triethylene glycol, tri-1,2-propylene glycol, glycerol, ethylene glycol monohexyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, ethylene glycol monobutyl acetate, diethylene glycol monoethyl ether Acetate, methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, 2-butanol, t-butanol, n-pentanol, i-pentanol, 2-methylbutanol, 2-pentanol, t-pentanol, 3-methoxybutanol, n-hexanol, 2-methylpentanol, 1-hexanol, 2-hexano 2-ethylbutanol, 1-heptanol, 2-heptanol, 3-heptanol, n-octanol, 2-ethylhexanol, 2-octanol, n-nonyl alcohol, 2,6-dimethyl-4-heptanol, n-decanol, Examples include cyclohexanol, methylcyclohexanol, 3,3,5-trimethylcyclohexanol, benzyl alcohol, diacetone alcohol, and terpineol. In addition to those specifically described, alcohol, glycol, glycol ether, glycol ester solvents, and water can be used as the dispersion medium.

  These may be used alone or in combination of two or more, and are selected in consideration of the evaporability and the solvent resistance of the printing equipment and the substrate to be printed according to the printing method. However, the boiling point affects the workability of the solvent. If the boiling point is too low, volatilization is rapid, so that workability is deteriorated due to an increase in defects due to precipitation of solids and an increase in cleaning frequency. Therefore, it is preferable that the temperature is 40 ° C. or higher in the coating or dispenser method, and it is preferable that the temperature is 120 ° C. or higher in the ink jet method, the screen method, and the offset method, more preferably 150 ° C. or higher, and 200 ° C. or higher. More preferably, The upper limit of the temperature is preferably 300 ° C. or less from the viewpoint of drying.

[substrate]
The substrate on which the ink in which the copper oxide is dispersed according to the present embodiment is applied or printed is not particularly limited, but an example of the material is described below.

  The substrate may be any of an inorganic material and an organic material. Examples of the inorganic material include glass such as soda lime glass, non-alkali glass, borosilicate glass, and quartz glass, and ceramic material such as alumina.

  Examples of the organic material include a polymer material and paper. As the polymer material, a resin film can be used. Polyimide, polyamide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyphenylene sulfide, polyetheretherketone, polysulfone, polycarbonate, polyetherimide, epoxy resin, Examples thereof include phenol resins, glass-epoxy resins, polyphenylene ether, polyphenylene sulfide, acrylic resins, polyolefins such as polyethylene and polypropylene, and liquid crystal polymer compounds. Examples of the paper include high-quality paper, medium-grade paper, coated paper, cardboard, corrugated cardboard, and other Western paper using general pulp as a raw material, and those using cellulose nanofiber as a raw material. In the case of paper, a material obtained by dissolving a polymer material or a material obtained by impregnating and curing a sol-gel material can be used. Further, these materials may be used by laminating or bonding.

  Furthermore, on these, as a smoothing layer, a barrier layer, an easy adhesion layer, etc., as a polymer material, polyimide, polyurethane, acrylic resin, epoxy, polyvinyl phenol, etc. may be used alone or in combination. And the like may be used by mixing particles such as inorganic materials. Further, as an inorganic material, silica, alumina, or the like may be formed by a sputtering method or an evaporation method. In addition, a sol-gel based material such as silica or alumina based film can be formed by a coating method.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the invention is not limited to these examples.

[Example 1]
In a mixed solvent of 3670 g of water and 1696 g of 1,2-propylene glycol (manufactured by Wako Pure Chemical), 391.5 g of copper (II) acetate monohydrate (manufactured by Wako Pure Chemical) was dissolved. Then, 114 g of hydrazine monohydrate (manufactured by Wako Pure Chemical Industries, Ltd.) was added and the mixture was stirred, and then separated into a supernatant and a precipitate by centrifugation.

  27.6 g of Disperbyk-118 (manufactured by Big Chemie) as a dispersant, 6.9 g of S-611 (manufactured by Seimi Chemical) and 455.5 g of ethanol (manufactured by Wako Pure Chemical Industries) were added to 200 g of the obtained precipitate. In addition, the mixture was dispersed using a homogenizer to obtain an ink.

  This ink was applied to the PEN substrate by No. The sample was coated using a 4 bar and dried at room temperature to obtain a sample for plasma treatment.

  In the plasma processing apparatus, the temperature of the stage 3 is set to 28 ° C., the microwave power is set to 1.50 kw, and a gas previously adjusted to a hydrogen concentration of 3% and a helium concentration of 97% into a chamber is mixed with a desired ratio as an oxygen source. And a pressure of 110 Pa in the chamber was adjusted, and the sample was treated for 2 minutes under different air ratios (oxygen concentration in the chamber), and the specific resistance was adjusted. It was measured. Table 1 shows the results. The sccm described here indicates a flow rate (ml / min) converted to a temperature of 0 ° C. and a pressure of 101.3 kPa. The thickness of the pattern after the plasma treatment was 0.25 μm.

[Comparative Example 1]
A sample for plasma treatment was obtained in the same manner as in Example 1. The process was performed in the same manner as in Example 1 except that no air was introduced into the chamber, and the specific resistance was measured. Table 1 shows the results.

  The above results are shown in FIG. From FIG. 3, it was found that introducing air (oxygen) into the chamber has an effect of lowering the resistance for the same processing time as compared with the case where oxygen is not introduced. From this, it is presumed that, when a predetermined resistance value is required, it is possible to shorten the processing time by introducing oxygen in the plasma processing, as compared with the case where oxygen is not introduced. Further, it was found that the ink can be satisfactorily conducted by setting the oxygen concentration lower than the hydrogen concentration.

  The conductive pattern of the present invention can be used for a wiring board, an antenna, a mesh-type transparent electrode, an electromagnetic wave shield, an electromagnetic wave reflection, a wiring for a flat display, an electrode, a wiring of a solar cell, and the like, and contributes to an improvement in productivity.

DESCRIPTION OF SYMBOLS 1 Plasma processing apparatus 2 Chamber 3 Stage 4 Window member 5 Microwave generator 6 Waveguide 7 Workpiece 8 Gas supply port 9 Exhaust port 10 Oxygen supply port 11 Adjustment valve 12 Slit 13 Dielectric 14 Internal pressure adjustment valve

Claims (6)

  An object to be processed in which a pattern is formed on a substrate using an ink in which copper oxide is dispersed is housed in a decompressed chamber, and plasma treatment is performed in a state where oxygen is present. Production method.   2. The method according to claim 1, further comprising performing plasma processing in a state where hydrogen gas is present in the chamber.   The method for producing a conductive pattern according to claim 1, wherein the oxygen is supplied into the chamber from outside.   The method for manufacturing a conductive pattern according to claim 1, wherein the copper oxide contains at least cuprous oxide.   The method for producing a conductive pattern according to claim 4, wherein the object to be treated includes the cuprous oxide and an organic compound having a phosphate group. An object to be processed in which a pattern is formed on a substrate using an ink in which copper oxide is dispersed, a chamber capable of accommodating the object,
Plasma generating means for generating plasma in the chamber,
Oxygen supply means capable of supplying oxygen into the chamber,
The plasma processing apparatus is characterized in that the object to be processed is subjected to plasma processing in a state where the oxygen is supplied to the chamber under reduced pressure by the oxygen supply unit.

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