JP2019029668A - Method for manufacturing conducting pattern and plasma processing device - Google Patents

Abstract

To provide: a method for manufacturing a conducting pattern, which enables especially the shortening of a processing time and the achievement of a low resistance; and a plasma processing device.SOLUTION: A method for manufacturing a conducting pattern according to the present invention comprises the steps of: loading an object to be processed, in which a pattern is formed on a substrate by using an ink with metal particles dispersed therein into a chamber in which a pressure is reduced; and performing a plasma process in the presence of water. In the invention, it is preferred to perform the plasma process in a state in which a hydrogen gas is present in the chamber.SELECTED DRAWING: Figure 1

Description

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

  As a method for forming a conductor pattern on a substrate, a method is known in which an ink in which metal particles are dispersed is drawn on a substrate by printing or coating, and then heated to sinter to form a conductor. Yes.

  However, in this method, for example, when silver is used, a conductor can be obtained even with a substrate material having low heat resistance such as PET or PEN. However, obtaining a conductor having a lower resistance value requires a required temperature. Is difficult and expensive. In addition, the time required for the processing requires several tens of minutes.

  As a method for forming a conductive pattern, a method is known in which conductivity is obtained by plasma treatment under reduced pressure (see Patent Document 1).

  In the method using plasma treatment, the applicable range such as metal particle dispersion, metal oxide dispersion, and metal compound is wide as applicable materials. In addition, it is known that this method can process a substrate having low heat resistance, and the processing time is shorter than that of a heating method using an oven or infrared heat treatment.

Japanese Patent No. 6072709

  However, in order to cope with mass production, further reduction in processing time is required without increasing the resistance value.

  As one of the factors that require time for the treatment, it can be considered that it takes time to decompose and remove organic compounds such as a dispersant and a surfactant that are added when the conductor raw material is made into ink.

  Therefore, the present invention is for solving the above-described conventional problems, and in particular, provides a method for manufacturing a conductive pattern and a plasma processing apparatus capable of reducing processing time and reducing resistance. For the purpose.

  The method for producing a conductive pattern according to the present invention is characterized in that plasma treatment is performed on an object to be processed on which a pattern is formed on a substrate using an ink in which metal particles are dispersed in a state where water is present.

  The method for producing a conductive pattern according to the present invention is characterized in that the object to be processed is accommodated in a decompressed chamber, and plasma processing is performed in the presence of water.

  In the present invention, it is further preferable to perform the plasma treatment in the presence of hydrogen gas in the chamber.

  In the present invention, it is further preferable to perform the plasma treatment in the presence of an inert gas in the chamber.

  In the present invention, it is preferable that the water is supplied into the chamber from the outside, or is attached to the object to be processed or a material different from the object to be processed.

  Further, the plasma processing apparatus according to the present invention includes a chamber capable of storing an object to be processed having a pattern formed on a substrate using ink in which metal particles are dispersed, and a plasma generating means for generating plasma in the chamber. Water supply means capable of supplying water into the chamber, and the object to be processed is plasma-treated in a state where water is supplied by the water supply means into the chamber under reduced pressure. It is characterized by.

  According to the method for producing a conductive pattern of the present invention, it is possible to reduce the processing time and reduce the resistance by performing the plasma treatment in the presence of water.

It is a flowchart which shows the manufacturing process of the electroconductive pattern of this embodiment. It is a schematic diagram of the plasma processing apparatus of this embodiment. It is a figure which shows the relationship between the plasma processing time and specific resistance in Example 1 and Comparative Example 1. It is a figure which shows the relationship between the water vapor | steam density | concentration in a chamber and specific resistance in Examples 2-4 and Comparative Examples 2 and 3. FIG.

  Hereinafter, an embodiment of the present invention (hereinafter abbreviated as “embodiment”) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

[Manufacturing process of conductive pattern]
FIG. 1 is a flow diagram showing the manufacturing process of the conductive pattern of the present embodiment. First, as shown in FIG. 1, ink is generated (step ST1). In this embodiment, ink in which metal particles are dispersed in a dispersion medium is generated. As an example, an ink containing silver is produced.

  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, planographic offset printing, reverse transfer printing, inkjet printing, and other printing methods, dispensers A drawing method can be used. As the coating method, various coating methods such as die coating, spin coating, slit coating, bar coating, knife coating, spray coating, and dip coating can be used.

  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 patterned substrate (object to be processed) is accommodated in the chamber 2 of the plasma processing apparatus 1 (step ST4).

  A plasma processing apparatus will be described. In the method of performing plasma treatment in the presence of water according to this embodiment, it is sufficient that water is decomposed in plasma and radicals can be generated. There is no limitation on the plasma generation method, the device structure, and the configuration, and in this embodiment, either the decompression method or the atmospheric pressure method, the electrode method, or the electrodeless method can be selected. Furthermore, the method of generating the high frequency necessary for plasma generation, the frequency, and the equipment configuration selection are not limited to a specific method or apparatus as long as the function can be exhibited. Here, as an example, a description will be given using a method in which a substrate with a pattern (object to be processed) is accommodated in a chamber and high-frequency energy is supplied in an electrodeless manner through a dielectric under reduced pressure.

  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. And an exhaust port 9 and an internal pressure adjusting valve 14. The workpiece 7 is placed on the surface of the stage 3.

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

  In FIG. 2, the microwave output from the microwave generator 5 reaches the window member 4 via the waveguide 6 through the isolator, the power monitor, and the tuner. The window member 4 has a slit 12. For example, the dielectric 13 is quartz. From the slit 12 of the window member 4, for example, a microwave of 2455 MHz ± 20 MHz is irradiated into the chamber 2 decompressed by the exhaust from the exhaust port 9 to generate surface wave plasma. The workpiece 7 is placed on the stage 3 and processed. The stage 3 may be provided with a function for heating or cooling the sample as necessary. Note that the method of generating plasma is not limited to the above. For example, opposing electrodes may be disposed in the chamber, and a high frequency power source may be connected between the electrodes to generate plasma between the electrodes. At this time, the workpiece 7 is placed on the surface of one of the electrodes and subjected to plasma treatment.

  Further, when the ink pattern is subjected to a conductor process using the plasma method, usually, either an inert gas or a reducing gas, or a mixed gas of a reducing gas and an inert gas is supplied from the gas supply port 8 to the chamber. The plasma is generated by microwaves. As a result, the object to be processed 7 in the chamber 2 is heated and at the same time, the organic substance contained in the dispersant added to the ink or the surfactant is decomposed and removed to obtain a conductive pattern. (Step ST6).

  Note that reducing gas is not always necessary if it is a metal that is difficult to oxidize, such as gold or silver. However, even if the metal surface is oxidized, if it is a method using a reducing gas, it is reduced and sintered. It becomes possible to do. As the reducing gas, hydrogen gas is most preferably used, but as a gas other than hydrogen gas, hydrocarbon gas such as carbon monoxide gas, ammonia gas, methane, ethane, propane, butane, acetylene, methanol, ethanol, propanol , Alcohols such as butanol, ethers such as dimethyl ether, diethyl ether, ethyl methyl ether, ethylene oxide, oxetane, tetrahydrofuran, glycols such as ethylene glycol, diethylene glycol, propylene glycol, aldehydes such as formaldehyde, acetaldehyde, propionaldehyde And formic acid can be used, and one or a mixture of two or more of these may be used.

  Moreover, helium gas which has the effect of making plasma generation easy can be preferably used as the inert gas. In addition to 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 mixed and used. In addition to facilitating the generation of plasma, the use of inert gas makes it possible to adjust the concentration of water by adding it, and can also be used as an adjustment means for adjusting to processing conditions suitable for the object to be processed. .

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

  However, the optimum conditions for the plasma processing differ depending on the structure of the plasma processing apparatus 1, the composition of the ink, the thickness of the pattern, the material of the base material, and the like. Therefore, it is necessary to adjust the optimum conditions for plasma processing in accordance with various situations. Further, a batch method in which the processing object 7 is put into and taken out from the chamber 2 for each processing, or a method of continuously supplying by a roll may be used. Further, a mechanism capable of heating or cooling the workpiece 7 may be provided. As for the temperature of the object 7 to be processed, when plasma processing is usually performed, sintering becomes easier as the temperature is higher. Therefore, a method of heating and processing is known. However, if the temperature is too high, deformation or melting of the substrate occurs. Therefore, it is preferable to set the temperature to be lower than the heat resistant temperature of the substrate. In this method, since the sintering ability is high, it is possible to sinter sufficiently even if the temperature setting is around room temperature or lower without heating the workpiece 7. In particular, when the heat-resistant temperature of the substrate is low, it may be set to room temperature or lower. The upper limit of the temperature 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 processing.

  After forming the conductive pattern, the object 7 is taken out from the chamber 2 (step ST7).

[Plasma treatment in the presence of water]
By the way, conventionally, plasma processing has required time. Ink has good dispersing agent added to prevent dispersion of fine particles dispersed, surfactant and leveling material added to prevent defects such as repelling, and good coating and printability for pattern formation Various additives such as a binder for thickening, a fluidity modifier, an adhesiveness imparting agent for imparting adhesiveness, and a stabilizer, which are added for the purpose of making them, are added.

  As a method for making a pattern formed of metal-dispersed ink into a conductor, a method by heating is generally employed. For example, in the case of silver ink, as the silver particles sinter to each other by heating, the dispersant, surfactant, etc. must be pushed out between the silver particles, which is one of the time-consuming factors. It was. On the other hand, in plasma treatment, decomposition and removal of organic substances such as dispersants and surfactants are promoted, so the treatment time is shorter than that of heat treatment alone, but from the viewpoint of equipment cost and productivity. Further reduction in processing time has been demanded. However, by adding a wide variety of additives, it takes time to decompose and remove these, and this has hindered time reduction even in plasma processing.

  Therefore, as a result of extensive research, the present inventor has found that plasma treatment can be performed in the presence of water to obtain the effects of shortening the treatment time and lowering the resistance value.

  Although the cause for obtaining such an effect is not clear, by performing plasma treatment in the presence of water, water is decomposed to generate oxygen radicals, hydroxy radicals, and hydrogen radicals.

  In particular, oxygen radicals and hydroxy radicals react with organic substances such as dispersants, surfactants and thickeners present in the pattern. Thus, the organic matter is quickly removed by oxidative decomposition, and further, the heat generated when the organic matter is oxidatively decomposed and the heat generated by the plasma are easily sintered. It is presumed that the processing time can be shortened and the resistance value can be reduced by the above mechanism. On the other hand, hydrogen radicals generated simultaneously with oxygen radicals and hydroxy radicals contribute to the reduction of metal oxides and promote sintering when metal particles that are easily oxidized or metal particles that are intentionally oxidized are used. . Therefore, when water is present, no reducing gas may be used.

  Note that the amount of water in the chamber 2 is 0.1% to 100%, preferably 1% or more, more preferably 5% or more, still more preferably 10% or more, and still more preferably in terms of gas partial pressure in the chamber. 15% or more, still more preferably 20% or more. Further, it is preferably 90% or less, more preferably 70% or less, still more preferably 50% or less, and still more preferably 40% or less.

[Water supply method]
Next, a method for supplying water vapor to the plasma processing apparatus will be described. Here, as an example, a method is described in which an object to be processed is housed in a chamber, microwaves are supplied through a dielectric under reduced pressure, and plasma is generated. Water can be supplied into the chamber 2 from the outside, or the object 7 or a material different from the object can be accommodated in the chamber and attached thereto.

  When water is supplied into the chamber 2 from the outside, for example, water can be mixed with an inert gas or a reducing gas outside the chamber 2 and supplied through the gas supply port 8 shown in FIG. Alternatively, as shown in FIG. 2, a water supply port 10 can be newly provided, and water can be supplied into the chamber 2 as water vapor from the water supply port 10. Alternatively, instead of through the line, for example, when the workpiece 7 is accommodated in the chamber 2, the operator may directly supply the chamber 2 by spraying water.

  In addition, the internal pressure of the chamber 2 when performing the plasma treatment is generally several tens to several hundreds Pa. Therefore, no condensation occurs inside the chamber 2 under a normal room temperature environment.

  As described above, when water is included in the gas, when one of the inert gas and the reducing gas, or both, water is mixed and supplied into the chamber 2, the gas is mixed depending on the mixing ratio. It is possible to control the proportion of water contained therein. Thus, since the ratio of water can be controlled by the mixing ratio, even if the amount of gas introduced into the chamber 2 is changed, the ratio of water contained in the gas can be maintained at a substantially constant value. In addition, when it is desired to supply only water vapor, the supply of inert gas or reducing gas may be stopped.

  Next, a specific method for adjusting the amount or ratio of water vapor contained in the gas introduced into the chamber 2 will be described. As an example, water is saturated in one or both of an inert gas and a reducing gas, and is mixed with one or both of an inert gas and a reducing gas not containing water, The method of adjusting is mentioned. Alternatively, water is introduced into a container that can withstand decompression, such as a tank, and once exhausted with a vacuum pump, gas components other than water existing in the space above the water and gas components dissolved in the water are removed. . And since the water vapor | steam of the vapor | steam pressure according to the temperature of water generate | occur | produces after a vacuum pump stop, the method of introduce | transducing water vapor | steam into the chamber 2 can be mentioned, controlling this. With this method, the water vapor content can be adjusted in the range of 0% to 100% by adjusting the ratio of water vapor to one or both of inert gas and reducing gas (however, In the present embodiment, 0% is not included). If the temperature of the water in the tank is controlled to, for example, 25 ° C., the water vapor pressure is 3170 Pa, and the internal pressure in the chamber 2 is several tens to several hundreds Pa. It is possible to send water vapor. At this time, if the temperature of the water is controlled to be equal to or lower than the temperature in the environment, condensation on the piping or the like can be prevented. However, since the vapor pressure decreases when the temperature is lowered, it is necessary to set it within a range where a necessary flow rate can be secured.

  As a method for monitoring and controlling the amount of water vapor, there are a method of manually adjusting an adjustment valve 11 (see FIG. 2) such as a needle valve, and a method of automatically using a known method such as a mass flow controller.

  The amount of water can also be adjusted by a method of monitoring and controlling the internal pressure. For example, first determine the total flow rate of gas including water vapor, and adjust the internal pressure adjustment valve 14 while flowing one or both of the inert gas and the reducing gas at that flow rate. Adjust the pressure to Next, a gas amount excluding water vapor is supplied. Although the internal pressure of the chamber 2 decreases, the adjustment valve 11 such as a needle valve may be adjusted to supply water vapor until the desired pressure set in advance is reached. Alternatively, a method of monitoring the pressure and adjusting the amount of water with an automatic valve or the like can be used.

  In addition to this, as a method of directly injecting water into the chamber 2, a method of discharging water into the chamber 2 while controlling the water through an injection valve so as to achieve a desired water vapor pressure while monitoring the internal pressure, or injection Taking advantage of the quantitative nature of the valve, it is possible to adopt a method of supplying a constant amount so that the required amount of water is obtained.

  An “injection valve” is used to inject a small amount of liquid. By controlling the opening time of the valve and the number of times per unit time, the liquid under pressure is controlled by the desired amount of water. Injection is possible.

  As an example of a valve opening / closing mechanism, a solenoid system and a system using a piezoelectric body are known and can be electrically controlled. In addition, since this method uses water under pressure, when the valve is opened, the liquid is sprayed in a mist-like manner and the vaporization is smooth due to the low pressure in the chamber 2. move on.

  Further, in the method of attaching water to the object 7 to be processed, water can be adsorbed in advance on the substrate of the object 7 to be processed, such as PET, PEN, ink coating, etc., and this can be put into the chamber 2. . In addition, since it is sufficient that water exists in the plasma processing environment, it is not always necessary to absorb water into the object to be processed, and a material that adsorbs water may be put into the chamber 2 separately from the object to be processed. Even in this method, it is possible to supply water in a plasma environment, and the effect of introducing water is manifested in the same manner as the method of attaching to the object to be processed. As an example of the place to put, for example, on the stage 3 or around the stage.

  As the material different from the object 7 to be processed, the same material as the base material such as PET or PEN, or other resin materials such as PMMA, polyvinyl alcohol, polyurethane, nylon, or cellulose, the shape is a film, a sheet, A board | plate material, a nonwoven fabric, the thing of a cloth form, etc. can be mentioned. In addition, any material having water adsorbability can be used. In addition to organic materials, inorganic materials can be used, and examples thereof include silica gel and molecular sieves on which water is adsorbed. Such a material other than the object 7 to be processed is placed on the stage 3 together with the object 7 to be processed, or placed in a place other than the stage 3 in the chamber 2. Processing is usually performed at a pressure in the chamber 2 of several tens to several hundreds Pa. As a result, the water adsorbed to the ink film, PET or PEN as the base material does not escape in a short time, is heated by starting the plasma treatment, promotes the release of water, and is necessary in the chamber. Water can be supplied.

  Adsorption of water to the ink film, PET, PEN, or the like, which is the base material of the object to be processed 7, can be performed by leaving it in an environment with a constant temperature and humidity or immersing it in water. In addition, a method of adding water to the dispersed ink and adsorbing the water to the dispersed particles can also be adopted.

  In the case of the method of adsorbing water to the object to be processed under the above-mentioned constant temperature and humidity conditions, the humidity condition affects the resistance after the plasma treatment, but the effect and ease of humidity control, From the viewpoint of condensation, the humidity condition is effective from over 0% to 100%, preferably 10% to 95%, more preferably 20% to 80%, and even more preferably 40% to 70%. Further, as a method for maximally adsorbing water, a method of immersing an object to be processed in water may be used.

  In the method of attaching water to the object to be processed 7 or an object other than the object to be processed, the timing of water supply is not particularly limited as long as plasma processing can be performed in a water atmosphere. That is, in the present embodiment, it is necessary to perform plasma treatment before water is removed. As a result, after the ink coating, PET, PEN substrate, etc. are heated by the plasma treatment, water is suddenly released into the chamber 2 and the plasma treatment in the presence of water becomes possible. As described above, it is sufficient that water is present during the plasma treatment, and even when the supply of water is limited, the effect of shortening the treatment time and reducing the resistance can be appropriately exhibited.

  As shown in FIG. 1, the water supply timing (step ST <b> 8) before accommodating the object 7 to be processed in the plasma processing apparatus 1 includes a drying process between the pattern formation and the drying process at the time of ink generation. You can choose later. Thus, when supplying water before a drying process, it is necessary to adjust a drying temperature and time appropriately so that all water may not escape by a drying process.

  Further, as the water supply timing (step ST9) after the object 7 is accommodated in the plasma processing apparatus 1, the plasma treatment process is performed between the process of accommodating the object 7 into the chamber 2 and the plasma treatment process. During the treatment process or the like can be selected, and the supply timing and time may be arbitrarily changed during the plasma treatment. For example, water can be constantly supplied during plasma processing, or water can be supplied at an arbitrary timing and time during plasma processing, or water supply and stop can be repeated during plasma processing. Also good.

  In the water supply process of step ST8, the above-described method of attaching the water to the object 7 can be adopted. In the water supply process of step ST9, the water supply method into the chamber 2 described above. Can be adopted.

[Effect of this embodiment]
As described above, in the present embodiment, it is possible to shorten the plasma processing time and reduce the resistance of the conductive pattern.

  The plasma treatment time can be about 15 to 240 seconds, and the resistance value of the conductive pattern can be about 4 to 90 μΩcm. Further, when compared with the conventional example in which plasma treatment is performed in the absence of water, the treatment time of the plasma treatment is the same in this embodiment and the comparative example, and the resistance value of the conductive pattern of the comparative example is 1. The resistance value of the conductive pattern of this embodiment can be lowered to about 0.2 to 0.8. Further, when the resistance value of the conductive pattern is the same between 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 0.2-0. It can be shortened to about 8.

  The plasma treatment time is preferably as short as possible from the viewpoint of productivity, but it is necessary to some extent from the viewpoint of reducing the variation in resistance value. Further, from the viewpoint of lowering the resistance value, the plasma treatment time should be long, but if it is too long, the productivity may be increased and the workpiece may be heated too much. For this reason, the plasma processing time is preferably 15 to 240 seconds, more preferably 25 to 210 seconds, and further preferably 35 to 180 seconds.

  In this embodiment, ink in which metal particles are dispersed can be used. Below, the ink used is demonstrated in detail.

[Ink used]
The metal component of the ink in which the metal particles are dispersed is not limited, and examples thereof include gold, silver, copper, nickel, tin, palladium, and the like, and alloys thereof, and particles coated with gold and silver. Among these, silver is preferably used. This is because, among metals, sintering at a low temperature is relatively easy, the resistance value is low, and oxidation is difficult. Furthermore, it is because it is easy to obtain ink in which silver particles having an average particle diameter of 100 nm or less are stably dispersed. As the particle size of the silver particles is smaller, the sintering becomes easier and the sintering temperature can be lowered. The lower limit of the average particle diameter is not particularly limited, but is preferably 1 nm or more from the viewpoint of ease of handling. If it is smaller than this, the amount of the dispersant used for maintaining the dispersion stability increases, and the amount of the dispersant component to be removed from between the metal particles during the sintering treatment tends to increase, so that sintering tends to be difficult. An ink in which silver particles are dispersed in an organic solvent or water is commercially available and can be used.

  In addition, surfactants and leveling materials added to prevent defects such as repellency due to improved wettability to the substrate during pattern formation, thickening added for the purpose of improving coating and printability for pattern formation Various additives such as a binder, a fluidity modifier, an adhesion imparting agent, and a stabilizer may be added as necessary.

[substrate]
The substrate on which the ink in which the metal particles are dispersed or applied is printed is not particularly limited, but an example of the material will be described below.

  The substrate may be an inorganic material or an organic material, and examples of the inorganic material include glass such as soda lime glass, alkali-free 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, such as polyimide, polyamide, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyphenylene sulfide, polyether ether ketone, polysulfone, polycarbonate, polyether imide, 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 made from general pulp as raw material, medium-quality paper, coated paper, cardboard, and other paper such as cardboard and cellulose nanofiber. In the case of paper, one obtained by dissolving a polymer material or one obtained by impregnating and curing a sol-gel material or the like can be used. Further, these materials may be used by being laminated together.

  Further, on these, as a smoothing layer, a barrier layer, an easy adhesion layer, etc., as a polymer material, polyimide, polyurethane, acrylic resin, epoxy, polyvinylphenol, etc. may be used alone or in combination. You may mix and use particles, such as inorganic materials, such as. As the inorganic material, silica, alumina, or the like may be formed by a sputtering method or a vapor deposition method. Further, a silica or alumina film can be formed by a coating method using a sol-gel material.

  Hereinafter, the present invention will be described in more detail by way of examples. However, the present invention is not limited to these examples.

[Example 1]
A silver particle dispersed ink (NPS-J) manufactured by Harima Kasei Co., Ltd. was used and applied to a PEN substrate (thickness: 100 μm) using a spin coater. The coating was performed under the condition that after silver ink was dropped on the PEN substrate, it was rotated at 400 rpm for 5 seconds and then at 3000 rpm for 20 seconds. Drying was performed at a temperature of 24 ° C. and a humidity of 30% for 24 hours to obtain a plasma processing sample. Subsequently, in the plasma processing apparatus, the temperature of the stage 3 was set to 28 ° C., the microwave power was set to 0.75 kW, and water vapor of 200 sccm was supplied into the chamber. Furthermore, the pressure in the chamber was adjusted with an adjusting valve 11 provided between the vacuum pump and the chamber, and was adjusted to 110 Pa. Then, the sample was subjected to a multi-point plasma treatment under conditions that differed only in treatment time, and the specific resistance was measured. The results are shown in Table 1. The film thickness of the pattern after the plasma treatment was 0.20 μm. In addition, sccm described here represents the flow rate (ml / min) converted into a temperature of 0 ° C. and a pressure of 101.3 kPa.

[Comparative Example 1]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, the plasma processing apparatus was supplied with a gas having a hydrogen concentration of 3% and a helium concentration of 97% instead of the water vapor of Example 1, and a plurality of conditions under the same conditions as in Example 1 except that the processing time was different. Point plasma treatment was performed and the specific resistance was measured. The results are shown in Table 1.

  The above results are shown in FIG. From FIG. 3, it was found that the presence of water in the plasma processing environment is effective in shortening the processing time and reducing the resistance.

[Example 2]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, in the plasma processing apparatus, the temperature of the stage 3 was set to 28 ° C., the microwave power was set to 0.75 kW, and 200 sccm was supplied into the chamber by combining both water vapor and a mixed gas of 3% hydrogen and 97% helium. . Furthermore, the pressure in the chamber was adjusted with a valve provided between the vacuum pump and the chamber, and was adjusted to 110 Pa. The plasma treatment time was set to 35 seconds, and a multipoint plasma treatment was performed under the conditions that differed only in the ratio of the water vapor and hydrogen helium mixed gas, and the specific resistance was measured. The results are shown in Table 2.

[Comparative Example 2]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, the plasma treatment was performed under the same conditions as in Example 2 except that the water vapor of Example 2 was not supplied, and the specific resistance was measured. The results are shown in Table 2.

[Example 3]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, in the plasma processing apparatus, instead of hydrogen and helium in Example 2, nitrogen was used, and multiple-point plasma processing was performed under the conditions that differed only in the ratio of water vapor and nitrogen, and the specific resistance was measured. The results are shown in Table 2.

[Example 4]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, the plasma treatment was performed under the same conditions as in Example 2 except that only the water vapor was supplied without supplying the mixed gas of hydrogen and helium in Example 2, and the specific resistance was measured. The results are shown in Table 2.

[Comparative Example 3]
A plasma processing sample was obtained in the same manner as in Example 1. Subsequently, the plasma treatment was performed under the same conditions as in Example 3 except that the water vapor of Example 3 was not supplied, and the specific resistance was measured. The results are shown in Table 2.

  The above results are shown in FIG. FIG. 4 shows that the presence of water in the plasma processing environment is effective in reducing resistance. It has also been found that gases other than water, such as hydrogen and inert gas, may be present, and that the higher the water concentration, the more effective the resistance reduction.

[Example 5]
A plasma processing sample was obtained in the same manner as in Example 1. This is 24 ° C. and humidity 30%, temperature 24 ° C. and humidity 40%, temperature 24 ° C. and humidity 60%, temperature 24 ° C. and humidity 75%, temperature 24 ° C. and humidity 95%, temperature 24 ° C. and water immersion, respectively. The sample was allowed to stand for 1 day under the conditions described above to absorb moisture. Each sample was accommodated in a plasma processing apparatus, the temperature of the stage 3 was set to 28 ° C., the microwave power was set to 0.75 kW, and a gas composed of 97% helium and 3% hydrogen was supplied into the chamber at a flow rate of 200 sccm. Further, the pressure in the chamber was adjusted by an adjusting valve 11 provided between the vacuum pump and the chamber, and was adjusted to 110 Pa. Then, the specific resistance was measured for each sample after the plasma treatment for 35 seconds. The results are shown in Table 3.

[Comparative Example 4]
A plasma processing sample was obtained in the same manner as in Example 1. This was left to dry for one day under conditions of a temperature of 24 ° C. and a humidity of approximately 0%. Subsequently, the plasma treatment was performed under the same conditions as in Example 5 using a plasma treatment apparatus, and the specific resistance was measured. The results are shown in Table 3.

  From the above results, it has been found that if water is absorbed by the object to be processed, it is possible to reduce the resistance as in the method of supplying water to the chamber of the plasma processing apparatus.

  The conductive pattern of the present invention can be used for wiring boards, antennas, mesh-type transparent electrodes, electromagnetic wave shields, electromagnetic wave reflections, flat display wirings, electrodes, solar cell wirings, and the like, and contributes to improvement in productivity.

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

Claims (6)

  A method for producing a conductive pattern, comprising subjecting an object to be processed, on which a pattern is formed on a substrate using an ink in which metal particles are dispersed, to plasma treatment in the presence of water.   The method for producing a conductive pattern according to claim 1, wherein the object to be processed is accommodated in a decompressed chamber and plasma treatment is performed in a state where water is present.   The method for manufacturing a conductive pattern according to claim 1, wherein plasma treatment is performed in a state where hydrogen gas is present in the chamber.   The method for manufacturing a conductive pattern according to any one of claims 1 to 3, further comprising performing plasma processing in the presence of an inert gas in the chamber.   5. The conductive material according to claim 1, wherein the water is supplied from the outside into the chamber, or is attached to the object to be processed or a material different from the object to be processed. Method for producing a sex pattern. A chamber capable of accommodating an object to be processed in which a pattern is formed on a substrate using ink in which metal particles are dispersed;
Plasma generating means for generating plasma in the chamber;
Water supply means capable of supplying water into the chamber,
The plasma processing apparatus, wherein the object to be processed is plasma-treated in a state where water is supplied by the water supply means into the chamber under reduced pressure.

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