JP2010199285A - Manufacturing method of wiring board, electronic element, and display - Google Patents

Abstract

A wiring board having a conductive layer having stable characteristics even when nanometal ink is baked at a low temperature is manufactured with high productivity.
A method for manufacturing a wiring board includes a step of applying a nanometal ink 11 containing metal fine particles 13 having a dispersion stabilizer 12 on a surface thereof onto a substrate 7, and removing a solvent component in the nanometal ink 11 to form a metal. A step of forming the fine particle coating film 16, a step of removing at least a part of the dispersion stabilizer 12 contained in the metal fine particle coating film 16 by ultraviolet irradiation treatment, UV ozone treatment, plasma treatment or solvent cleaning treatment, A step of forming the metal conductive layer 18 by heating and firing the metal fine particle layer 17 from which the stabilizer 12 has been removed in the air.
[Selection] Figure 1

Description

  The present invention relates to a method for manufacturing a wiring board, and an electronic element and a display device provided with the wiring board obtained by this method.

Organic thin film transistors using organic semiconductor materials have been intensively studied. Advantages of using an organic semiconductor material for the transistor include the following.
1. High flexibility due to diversity of material composition, manufacturing method and product form.
2. Easy to increase the area.
3. A simple layer structure is possible and the manufacturing process can be simplified.
4). The element can be manufactured by a printing method or the like, and therefore the price of the manufacturing apparatus is low. By using a method such as a printing method, a spin coating method, or an immersion method, a thin film or a circuit can be easily formed. As a result, it can be manufactured at an order of magnitude cheaper than a conventional Si-based semiconductor device.

One of the parameters indicating the characteristics of the thin film transistor is the current _on / off ratio (I _on / I _off ). In the organic thin film transistor, a current I _ds flowing between the source and drain electrodes in the saturation region is expressed by the following formula (1).
_{I ds = μC in W (V} G -V TH) 2 / 2L ··· equation (1)
Here, mu is the field-effect _{mobility, C in} the capacitance per unit area of the gate insulating film, W is a channel width, L is channel length, _{V G} is the gate _{voltage, V TH} is a threshold voltage It is. C _in is expressed by the following formula: C _in = εε ₀ / d
Where ε is the relative dielectric constant of the gate insulating film, ε ₀ is the dielectric constant of vacuum, and d is the thickness of the gate insulating film.

From equation (1), to increase the on-current,
1. 1. Improving field effect mobility. 2. Shorten the channel length. It can be seen that increasing the channel width is effective. Field effect mobility largely depends on material characteristics, and materials are being developed to improve mobility.

  On the other hand, since the channel length is derived from the element configuration, attempts have been made to improve the on-current by devising the element configuration. Generally, in order to shorten the channel length, it is known to shorten the distance between the source and drain electrodes.

  Since organic semiconductor materials do not have large field effect mobility compared to inorganic semiconductor materials such as silicon semiconductors, the channel length is usually at least 10 μm or less, preferably 5 μm or less.

As a method for accurately shortening the distance between the source and drain electrodes, photolithography used in an Si process is generally used. This photolithography includes the following steps.
1. Applying a photoresist layer on a substrate having a thin film layer (resist application);
2. Removing the solvent by heating (pre-baking);
3. Irradiate ultraviolet light through a hard mask drawn with a laser or electron beam according to pattern data (exposure);
4). Removing the exposed resist with an alkaline solution (development);
5). Curing the unexposed (patterned) resist by heating (post-baking);
6). Immersion in an etching solution or exposure to an etching gas to remove the thin film layer where there is no resist (etching);
7). The resist is removed with an alkaline solution or oxygen radical (resist stripping).
After each thin film layer is formed, the above process is repeated to complete the active device. Although the photolithography method can accurately form a fine pattern, the expensive equipment and the length of the process increase the cost.

  Therefore, in order to reduce manufacturing costs, attempts have been made to form electrode patterns using a printing method such as an inkjet printing method. The ink jet printing method is a method of forming a conductive pattern by printing an ink that becomes a conductor after film formation on a substrate by an ink jet method, and drying and baking. When the ink jet printing method is used, the electrode pattern can be directly drawn, so that the material usage rate increases, and there is a possibility that the manufacturing process can be simplified and the cost can be reduced.

  However, in the ink jet printing method, it is difficult to reduce the discharge amount, and it is difficult to form a pattern of 30 μm or less in consideration of landing accuracy due to mechanical errors and the like. For this reason, it is difficult to produce a high-definition device using only the inkjet printing method. Therefore, in order to manufacture a high-definition device, some device is required. As one method, the present inventors use a wettability changing material whose critical surface tension is changed by applying energy, and a printing method. Has been proposed, and a multilayer structure capable of easily forming a fine pattern has been proposed (see, for example, Patent Document 1). The conductive layer of this laminated structure is conceptually shown as a general configuration, for example, as shown in FIGS.

  As the ink used in the ink jet printing method, a so-called nano metal ink in which metal fine particles, particularly particles having a primary particle size of the order of nm is dispersed in a liquid is often used. In the nanometal ink, a dispersion stabilizer is provided around the fine metal particles so that the fine metal particles do not aggregate in the liquid. Since the dispersion stabilizer is an organic material, the dispersion stabilizer is removed by oxidation and decomposition by heating after applying the nanometal ink to the substrate and drying it. Further, since the particle size of the metal fine particles is on the order of nm, the melting point is lower than that of the bulk body, and the nanoparticles are fused together at a firing temperature lower than the melting point of the bulk, so that the electrode pattern becomes a conductor. For the nanometal ink, single metals such as gold, silver, copper, platinum, palladium, and nickel and their alloys are used, and silver and its alloys are often used particularly in terms of price and firing temperature.

  Normally, the dispersion stabilizer is removed by the firing process, but removal by heating does not remove 100% of the dispersion stabilizer, and the residual amount tends to vary. If the dispersion stabilizer remains, the fusion between the metals is hindered and the resistance value becomes high. In addition, since the dispersion stabilizer remaining on the surface of the source electrode and the drain electrode affects the electrical contact between the electrode and the organic semiconductor, there is a problem that the characteristics of the manufactured organic transistor vary. In order to prevent this problem, it is necessary to design a dispersion stabilizer that can be fired at a sufficiently high temperature so that the dispersion stabilizer can be decomposed, or can be sufficiently removed even at a low temperature. However, in the former case, the advantage of the nanometal ink that the firing temperature can be lowered is impaired, and in the latter case, the storage stability at room temperature is lowered.

  As a technique for solving the above problems, a technique is disclosed in which the nanometal ink coating layer surface after drying and before firing is irradiated with energy rays and then heated in a range of 50 ° C. to 200 ° C. in a non-oxidizing gas atmosphere. (Patent Document 2). However, firing in a non-oxidizing gas atmosphere has the problem that the atmosphere in the firing furnace needs to be replaced and mass productivity is not good.

  The first object of the present invention is to solve the above problems and to manufacture a wiring board having a conductive layer having stable characteristics even when the nanometal ink is baked at a low temperature without damaging the stability at room temperature with high productivity. Is to provide a method. A second object of the present invention is to provide an electronic element and a display device having excellent electrical characteristics using the wiring board produced by the above method.

  As a result of studies conducted by the present inventors to solve the above-mentioned problems, a nanometal ink containing metal fine particles of gold, silver, platinum, or the like, or an alloy thereof is coated on a substrate, dried, and then fired. The present invention has been completed by finding that a conductive layer having good conductive performance can be formed even by firing at a low temperature in the air by providing a step of removing the dispersion stabilizer in advance.

That is, the present invention is a method of manufacturing a wiring board in which a wiring made of a conductive layer is formed on a substrate,
Applying an ink containing fine metal particles having a dispersion stabilizer on the surface onto the substrate or an arbitrary layer on the substrate;
Removing a solvent component in the ink to form a metal fine particle coating film;
Removing at least a portion of the dispersion stabilizer contained in the metal fine particle coating film;
Forming the conductive layer by heating and firing the fine metal particle coating film from which the dispersion stabilizer has been removed; and
A method for manufacturing a wiring board, comprising:

  In the method for manufacturing a wiring board according to the present invention, the metal fine particles are preferably gold, silver, palladium, platinum, rhodium, ruthenium, iridium, or an alloy thereof.

Further, in the method for manufacturing a wiring board according to the present invention, the substrate includes a material whose surface energy is changed by applying energy, and a relatively high surface energy portion having a large surface energy and a low surface energy portion having a small surface energy. And a wettability changing layer having at least two parts having different surface energies,
It is preferable to apply the ink to the high surface energy portion of the wettability changing layer.

  In the method for manufacturing a wiring board of the present invention, it is preferable that the dispersion stabilizer is removed by an ultraviolet irradiation treatment.

  In the method for manufacturing a wiring board according to the present invention, it is preferable that the dispersion stabilizer is removed by UV ozone treatment.

  In the method for manufacturing a wiring board according to the present invention, it is preferable that the dispersion stabilizer is removed by plasma treatment.

  In the method for manufacturing a wiring board according to the present invention, it is preferable that the dispersion stabilizer is removed by a washing treatment with a solvent.

  The electronic device of the present invention includes a wiring board produced by any one of the above-described wiring board manufacturing methods.

  A display device of the present invention includes the electronic element and a display element.

  According to the method for manufacturing a wiring substrate of the present invention, since the step of removing at least a part of the dispersion stabilizer contained in the metal fine particle coating film is provided, the removal of the non-volatile components in the metal fine particle coating film is uniform. As a result, the amount of non-volatile components and variations thereof are small, and a conductive layer exhibiting good conductive performance can be stably formed. In addition, by providing a step of removing at least a part of the dispersion stabilizer contained in the coating film of the metal fine particles, a dispersion stabilizer is blended in the ink to obtain stability at room temperature, and a firing step. Then, even if baking is performed at a relatively low temperature, the specific resistance of the conductive layer can be sufficiently reduced.

  In addition, the electronic device and the display device of the present invention formed using the wiring board manufactured by the above method have excellent electrical characteristics.

It is process drawing explaining the main processes of this invention method. It is a cross-sectional schematic diagram which shows the example of a fundamental structure of a laminated structure. It is a schematic diagram which shows an example of the cross-sectional structure of a wettability change layer. It is a schematic diagram which shows another example of the cross-sectional structure of a wettability change layer. It is a schematic diagram which shows another example of the cross-sectional structure of a wettability change layer. It is a schematic diagram which shows an example of the structure of the surface of a wettability change layer. It is a schematic diagram which shows another example of the structure of the surface of a wettability change layer. It is a schematic diagram which shows another example of the structure of the surface of a wettability change layer. It is a conceptual diagram which shows the structure of the polymeric material which has a hydrophobic group in a side chain. 1 is a diagram illustrating a configuration of a transistor which is an example of an electronic element according to the present invention. It is process drawing which shows an example of the production process of a laminated structure. It is drawing which shows the structural example of an inkjet apparatus. It is drawing which shows the structural example of a transistor element array substrate. 10 is a diagram illustrating a configuration of a display device manufactured in Example 4;

  Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. In the nanometal ink 11 used in the present invention, the metal fine particles 13 coated with the dispersion stabilizer 12 are, for example, polar solvents such as water, ethanol, ethylene glycol, and glycerin and mixtures thereof, or nonpolar such as toluene and acetone. It is dispersed in a vehicle 14 such as a solvent or a mixture thereof. The vehicle 14 may contain a dispersion stabilizer 12 and additives added for ink characteristics. As shown in FIG. 1A, first, a nano metal ink 11 is applied on the substrate 7. As the coating method, various coating methods such as spin coating, blade coating, bar coating, and spray coating, and various printing methods such as offset printing, gravure printing, inkjet printing, and screen printing can be used.

  Next, the nanometal ink 11 is dried [see FIG. 1B]. Volatile components such as a solvent in the vehicle 14 are lost by drying, and the metal fine particles 13 and the non-volatile components 15 such as the dispersion stabilizer 12 and additives remain on the substrate 7 to form the metal fine particle coating film 16. Examples of the drying method include transpiration by natural standing, heat drying, air drying, and reduced pressure drying. At this time, in addition to the metal fine particles 13, the metal fine particle coating film 16 contains a non-volatile component 15 such as a dispersion stabilizer 12 or an additive. Examples of the dispersion stabilizer 12 include organic materials such as polyvinyl pyrrolidone and polyvinyl alcohol.

  Next, the non-volatile component 15 in the metal fine particle coating film 16 is removed. As a method for removing the non-volatile component 15, for example, the metal fine particle coating film 16 is irradiated with a high energy ray such as an ultraviolet ray or an electron beam, and the non-volatile component is decomposed and removed by the high energy ray. Irradiation to ozonize oxygen in the atmosphere and decompose non-volatile components with the ozone (UV ozone treatment method), to generate plasma by applying a high electric field, and to decompose non-volatile components with plasma ( Plasma treatment method), a method of removing the non-volatile component 15 by applying a liquid capable of dissolving the non-volatile component 15 or immersing in the liquid (solvent method), and the like.

Irradiation with high energy rays such as ultraviolet rays and electron beams can be performed by, for example, irradiating deep UV with a wavelength of 200 nm or less under conditions of 10 J / cm ² . In this method, the non-volatile component 15 in the irradiated part can be efficiently removed. However, since the high energy rays do not easily reach the shaded portion, the lower side of the laminated metal fine particles 13 may be difficult to remove.

The UV ozone treatment method can be performed, for example, under the condition of irradiating ultraviolet rays having a wavelength of 365 nm at 5 W / cm ² for 10 minutes. This method is more effective because ozone can enter and process the gap between the stacked metal fine particles 13.

  The plasma treatment method can be performed, for example, using oxygen as a source gas and a 500 W power supply for 3 minutes. In this method, since plasma is accelerated by an electric field and processed, efficient removal can be expected.

  The solvent cleaning method depends on the type of the vehicle of the nanometal ink, but when the vehicle is an ink of a polar solvent, it can be performed, for example, by immersing in ethanol at room temperature for 10 minutes. In this method, it is necessary to select a solvent that dissolves the non-volatile component 15, but the non-volatile component 15 can be removed to every corner between the metal fine particles 13. As the solvent, a solvent that dissolves the dispersion stabilizer and does not damage the substrate 7 and the metal fine particles 13 is selected. Examples of such a solvent include alcohols such as methanol, ethanol and 2-butanol, polar solvents such as water and acetone, alkanes such as pentane and hexane, and toluene.

  The metal fine particle layer 17 from which the non-volatile components 15 are removed is left on the substrate 7 by any one or combination of the above methods [see FIG. 1 (c)]. Next, the substrate 7 on which the metal fine particle layer 17 from which the non-volatile component 15 has been removed is formed is fired in a firing furnace in an atmospheric atmosphere. Since the finely divided metal in the metal fine particle layer 17 is melted at a temperature lower than that of the bulk body, the fine particles are fused at a low temperature to form the metal conductive film 18 [FIG. 1 (d)].

  In the above method, since the removal process of the non-volatile component 15 is performed uniformly, the amount of non-volatile component in the film and its variation can be suppressed to a small value. Therefore, the specific resistance is small by firing, and a good metal conductive film 18 can be stably formed. At that time, in the method of the present invention, firing can be performed at a low temperature. For example, the firing can be completed at a temperature in the range of 100 to 180 ° C, preferably in the range of 140 to 160 ° C. When the firing temperature is less than 100 ° C., even if the non-volatile component 15 is removed, the fusion between the metal fine particles is insufficient and the resistance is not low, and when the firing temperature is higher than 180 ° C. (for example, 200 ° C. or more), Even if the volatile component 15 is not removed, the resistance becomes sufficiently low, so that the effect of providing the step of removing the non-volatile component 15 cannot be fully utilized.

  Further, in the method of the present invention, since firing is performed in an air atmosphere, it is not necessary to replace the firing atmosphere with gas or the like, and firing with high productivity can be performed.

  In the baking so far, the step of FIG. 1C is omitted, and the film containing the non-volatile component 15 is baked in the air atmosphere by the baking furnace. By heating, the non-volatile component 15 is decomposed by oxygen in the atmosphere and has a form similar to that shown in FIG. 1C. The metal fine particles 13 are fused to form the metal conductive film 18 shown in FIG. However, there is a difference in decomposition of the non-volatile component 15 depending on the temperature distribution and oxygen distribution in the firing furnace, resulting in a difference in the amount of remaining non-volatile component, which causes variations in the specific resistance of the metal conductive film 18. It was a cause and a problem. In the method of the present invention, the problem of the conventional method can be solved by providing the step of removing the non-volatile component 15 in the metal fine particle coating film 16.

  As the metal fine particles 13 dispersed in the nanometal ink 11, for example, gold, silver, palladium, platinum, rhodium, ruthenium, iridium and alloys thereof are preferable. Since these metals and alloys are difficult to oxidize and have high self-reducing properties, even when fired in an air atmosphere containing oxygen, they are not easily oxidized by heating, but rather the reduction proceeds. As a result, the metal conductive film 18 having excellent conductivity is obtained. Can be formed. The particle size of the metal fine particles 13 is preferably in the range of 1 nm to 1000 nm, for example. When the particle size of the metal fine particles 13 is less than 1 nm, the proportion of the dispersant is larger than that of the metal fine particles, so that there is less contact between the metal fine particles after the removal of the dispersant, so that the resistance is not lowered. When the particle size of the metal fine particles 13 exceeds 1000 nm, the melting point does not drop due to the particle size and the resistance does not become low.

  The metal conductive film 18 obtained by the above steps can be used as circuit wiring for electronic components. For example, a stacked structure in which wirings are sequentially formed by the above method with an insulating film interposed therebetween and a semiconductor layer is provided functions as a transistor (electronic element). Details will be described later.

  Next, a configuration example of a laminated structure that can be used for a wiring board to be manufactured by the method of the present invention will be described. FIG. 2 is a schematic cross-sectional view showing an example of the basic configuration of the laminated structure. The laminated structure 1 of the present embodiment is configured based on, for example, a wettability changing layer 2 formed on a substrate (not shown). Here, the wettability changing layer 2 is a layer made of a material whose critical surface tension changes with the application of energy. In the present embodiment, the wettability changing layer 2 has at least two parts having different critical surface tensions. It has a large high surface energy part 3 and a low surface energy part 4 with a smaller critical surface tension. Here, a gap between two high surface energy portions 3 in the illustrated example is set to a minute gap of about 1 to 5 μm, for example. In addition, conductive layers 5 are formed at portions of the high surface energy portion 3 with respect to the wettability changing layer 2. Further, if necessary, the semiconductor layer 6 is provided so as to be in contact with at least the low surface energy portion 4 with respect to the wettability changing layer 2.

In the present invention, the terms “high surface energy” and “low surface energy” are used in a relative meaning, but the critical surface tension (γ _C ) of the low surface energy portion 4 of the wettability changing layer 2 is 40 mN / m or less is preferable. The difference between the critical surface tension (γ _C ) of the low surface energy part 4 and the critical surface tension (γ _C ) of the high surface energy part 3 is preferably 10 mN / m or more. When the critical surface tension (γ _C ) of the low surface energy part 4 is larger than 40 mN / m, the surface of the low surface energy part 4 is easily wetted with the nanometal ink. When the difference between the critical surface tension (γ _C ) of the low surface energy part 4 and the critical surface tension (γ _C ) of the high surface energy part 3 is smaller than 10 mN / m, the critical surface of the low surface energy part 4 Even if the tension (γ _C ) is 40 mN / m or less, the spread of the nanometal ink 11 applied to the high surface energy portion 3 is difficult to stop at the interface between the low surface energy portion 4 and the high surface energy portion 3, and the electrode pattern is a design value. In some cases, such a problem may occur that the gap between the electrodes becomes larger or the space between the electrodes is crushed and short-circuited.

  Since the wettability changing layer 2 is a layer made of a material whose critical surface tension changes when energy is applied, the material constituting the wettability changing layer 2 is the amount of change in the critical surface tension before and after energy application. A large one is preferable. In the case of such a material, by applying energy to a part of the wettability changing layer 2 and forming patterns having different critical surface tensions composed of the high surface energy part 3 and the low surface energy part 4, the conductive material can be obtained. The contained ink tends to adhere to the high surface energy portion 3 and hardly adheres to the low surface energy portion 4. That is, the ink containing the conductive material selectively adheres to the high surface energy part that is lyophilic and solidifies it, whereby the conductive layer 5 that becomes the electrode is patterned.

Regarding the wettability (adhesiveness) of the liquid to the solid surface, the following Young's formula is established.
γ _S = γ _SL + γ _L cos θ
Here, γ _S is the surface tension of the solid, γ _SL is the interface tension between the solid and the liquid, and γ _L is the surface tension of the liquid.

The surface tension is substantially synonymous with the surface energy and has the same value. When cos θ = 1, θ = 0 ° and the solid is completely wetted. The value of γ _L at this time is γ _S -γ _SL , which is called the critical surface tension γ _{C of the} solid. γ _C can be easily determined by plotting the relationship between the surface tension of the liquid and the contact angle using a liquid whose surface tension is known, and obtaining the surface tension at which θ = 0 ° (cos θ = 1) ( Zismann plot). A solid surface with a large γ _C is easily wetted with a liquid, and a solid surface with a small γ _C is difficult to wet with a liquid. The contact angle θ can be measured by a known droplet method.

  Examples of the semiconductor layer 6 include inorganic semiconductors such as CdSe, CdTe, and Si, organic low molecules such as pentacene, anthracene, tetracene, and phthalocyanine, polyacetylene conductive polymers, polyparaphenylene and derivatives thereof, and polyphenylene vinylene and derivatives thereof. Organic semiconductors such as polyphenylene-based conductive polymers such as polypyrrole and derivatives thereof, polythiophene and derivatives thereof, heterocyclic conductive polymers such as polyfuran and derivatives thereof, and ionic conductive polymers such as polyaniline and derivatives thereof However, when an organic semiconductor is used as described above, the effect of improving the properties by the wettability changing layer 2 appears more remarkably.

  Here, the wettability changing layer 2 may be made of a single material or may be made of two or more kinds of materials. In the case of being composed of two or more materials, specifically, by mixing a material having a greater wettability change with a material having a greater electrical insulation property, the electrical insulation is excellent and the wettability change is also achieved. It is possible to provide an excellent wettability changing layer 2. When the wiring pattern is already formed on the substrate and another wiring pattern is formed on the insulating layer via the insulating layer, the wettability changing layer 2 having excellent electrical insulation is effective. In this case, the wettability changing layer 2 can serve as an insulating layer as it is without providing an insulating layer separately. In particular, when the wettability changing layer 2 is used as a gate insulating film layer of a thin film transistor (TFT), high electrical insulation is important. In addition, since it is possible to use a material that has a large change in wettability but has a problem in film formability, more materials can be selected. Specifically, when one material has a greater change in wettability but has a high cohesive force and is difficult to form a film, this material should be mixed with the other material with good film formability. Thus, the wettability changing layer 2 can be easily manufactured.

  A schematic cross-sectional view of the wettability changing layer 2 is shown in FIG. For example, on the layer composed of the first material 71, a layer composed of the second material 72, which is more excellent in wettability change than the first material 71, is clearly separated and laminated. The first material 71 is a material that is more excellent in electrical insulation than the second material 72. Such a structure can be produced by sequentially laminating a layer made of the second material 72 after producing a layer made of the first material 71. As a manufacturing method, a vacuum process such as vacuum vapor deposition can be used, or a coating process using a solvent can be used.

  Moreover, it is also possible to manufacture by applying a solution obtained by mixing the first material 71 and the second material 72 to the substrate and drying it. When the polarity of the second material 72 is relatively small or when the molecular weight is relatively small, the second material 72 moves to the surface side and forms a layer before the solvent evaporates during drying. To do. When the coating process is used, the layer made of the first material 71 and the layer made of the second material 72 are often not clearly separated by the interface, as shown in the schematic cross-sectional view of FIG.

  The first material 71 / second material 72, which is the composition ratio of the first material 71 having relatively high electrical insulation and the second material 72 having a relatively large change in wettability, has a weight ratio of 50. / 50 to 99/1 is preferable. As the weight ratio of the second material 72 increases, the electrical insulating property of the wettability changing layer 2 becomes low and becomes unsuitable as an insulating layer of an electronic element. On the other hand, when the weight ratio of the first material 71 is increased, the wettability change is reduced, so that the patterning of the conductive layer is not good. Therefore, the mixing ratio between the two is desirably 60/40 to 95/5, and more desirably 70/30 to 90/10.

  As shown in the schematic cross-sectional view of FIG. 4, the layer made of the first material 71 and the layer made of the second material 72 may not be clearly separated by the interface. Further, as shown in FIG. 4 or FIG. 5, the first and second materials 71 and 72 may be mixed with a predetermined concentration distribution in the film thickness direction.

  When the wettability changing layer 2 is composed of two or more kinds of materials, it may have a laminated structure of two or more layers, and has a predetermined concentration distribution in the film thickness direction without having a layer structure. Materials may be mixed.

  As shown in the schematic plan view of FIG. 6, it is desirable that the wettability changing layer surface 2a on the side not in contact with the substrate has a surface in which the second material 72 is uniformly dispersed. However, if fine patterning is possible, a state in which the first material 71 is dispersed while the second material 72 is uniformly dispersed as shown in the schematic plan view of FIG. As shown in the schematic plan view, the layers may be separated to form a so-called sea-island structure. The sea-island structure can be observed using an optical microscope, micro-infrared, Raman spectroscopy, or the like. In particular, if the island structure has a diameter of about 5 μm, the material component is determined by micro-infrared spectroscopy. It is also possible to specify.

The wettability changing layer 2 is desirably made of a polymer material having a hydrophobic group in the side chain. Specifically, as shown in the conceptual diagram of FIG. 9, the side chain R having a hydrophobic group directly or via a bonding group (not shown) on the main chain L having a skeleton such as polyimide or (meth) acrylate. Can be mentioned. As the hydrophobic group, —CH ₂ CH ₃ , —CH (CH ₃ ) ₂ , —C (CH ₃ ) ₃ , —CF ₂ CH ₃ , —CF ₂ CF ₃ , —CF (CF ₃ ) ₂ , —C _{(CF 3) 3, -CF 2} H, can be a group having a terminal structure such as -CFH _2. Also in this case, in order to facilitate the orientation of molecular chains, a group having a long carbon chain length is preferable, and a group having 4 or more carbon atoms is more preferable. The alkyl group contains a halogen atom, a cyano group, a phenyl group, a hydroxyl group, a carboxyl group, or a phenyl group substituted with a linear, branched or cyclic alkyl group or alkoxy group having 1 to 12 carbon atoms. Also good. It is considered that the more R binding sites, the lower the surface energy (the smaller the critical surface tension) and the more lyophobic. Due to ultraviolet irradiation or the like, a part of the bond is broken, so that the critical surface tension increases and the liquid becomes lyophilic. In addition to this, examples of the hydrophobic group include an organosilicon group that can be represented by —SiR ₃ (where R is an organic group containing a siloxane bond).

Here, in the laminated structure 1 of the present embodiment, since the semiconductor layer 6 is in contact with the low surface energy portion 4 of the wettability changing layer 2, it is considered that the physical properties of the part affect the characteristics of the semiconductor layer 6. It is done. In this case, it is desirable that the critical surface tension (γ _C ) of the low surface energy portion 4 of the wettability changing layer 2 is 40 mN / m or less.

  In consideration of forming the semiconductor layer 6 on the wettability changing layer 2, the polymer material having a hydrophobic group in the side chain preferably includes a polyimide resin. Since the polyimide resin is excellent in solvent resistance and heat resistance, when the semiconductor layer 6 is formed on the wettability changing layer 2, the polyimide resin swells or cracks due to a temperature change caused by the solvent or baking. Absent.

  Further, when the wettability changing layer 2 is composed of two or more kinds of materials, in consideration of heat resistance, solvent resistance and affinity, materials other than the polymer material having a hydrophobic group in the side chain are also polyimide resins. It is desirable to consist of.

  By the way, the hydrophobic group defines the surface tension of the low surface energy part 4. However, in the method for manufacturing a wiring board according to the present invention, as described later, if the low surface energy part 4 repels ink too much, the high surface energy part 3. Since the protrusion from the surface cannot be measured, a material in which the surface energy of the low surface energy portion 4 does not become too low is desirable. Therefore, the surface energy of the low surface energy portion 4 is desirably 30 mN / m or more.

  The hydrophobic group of the polyimide resin having a hydrophobic group in the side chain used in the present embodiment can have any of the structures represented by the following chemical formulas (1) to (5), for example.

In the chemical formula of the formula (1), X is -CH ₂ - or _CH 2 CH ₂ -,, ^{A 1} is substituted with 1,4-cyclohexylene, 1,4-phenylene or 1-4 fluorines 1 , 4-phenylene, A ² , A ³ and A ⁴ are each independently a single bond, 1,4-cyclohexylene, 1,4-phenylene or 1,4-substituted with 1 to 4 fluorines Phenylene, B ¹ , B ² and B ³ are each independently a single bond or CH ₂ CH ₂ —, B ⁴ is alkylene having 1 to 10 carbon atoms, and R ³ , R ⁴ , R ^5. , R ⁶ , and R ⁷ are each independently alkyl having 1 to 10 carbon atoms, and p is an integer of 1 or more.

  In the chemical formula of the formula (2), T, U and V are each independently a benzene ring or a cyclohexane ring, and any H on these rings is alkyl having 1 to 3 carbon atoms, fluorine having 1 to 3 carbon atoms. Optionally substituted with substituted alkyl, F, Cl or CN, m and n are each independently an integer from 0 to 2, h is an integer from 0 to 5, and R is H, F, Cl, CN or a monovalent organic group, and two U's when m is 2 or two V's when n is 2 may be the same or different.

In the chemical formula of formula (3), the linking group Z is CH ₂ , CFH, CF ₂ , CH ₂ CH ₂ or CF ₂ O, and the ring Y is 1,4-cyclohexylene or 1 to 4 H are F Or 1,4-phenylene which may be replaced by CH ₃ , wherein A ^{1 to} A ³ are each independently a single bond, 1,4-cyclohexylene or 1 to 4 H are F or CH ₃ 1,4-phenylene which may be substituted, and B ^{1 to} B ³ are each independently a single bond, an alkylene having 1 to 4 carbon atoms, an oxygen atom, an oxyalkylene having 1 to 3 carbon atoms, or 1 to 1 carbon atoms. 3 is alkyleneoxy, R is H, alkyl having 1 to 10 carbon atoms in which arbitrary CH ₂ may be replaced with CF ₂ , or 1 carbon atom in which one CH ₂ may be replaced with CF ₂ ~ 9 alkoxy or alkoxyalkyl Binding position of the amino group to the benzene ring is arbitrary position. However, when Z is CH ₂ , all of B ^{1 to} B ³ are not simultaneously alkylene having 1 to 4 carbon atoms, Z is CH ₂ CH ₂ , and ring Y is 1, 4 When -phenylene, both A ¹ and A ² are not a single bond, and when Z is CF ₂ O, ring Y is 1,4-cyclohexylene. Absent.

In the chemical formula of formula (4), R2 is an alkyl group having 1 to 12 carbon hydrogen atom or a C, _{Z 1} is CH ₂ group, m is 0 to 2, ring A is a benzene ring or a cyclohexane ring Yes, l is 0 or 1, each Y ₁ is independently an oxygen atom or a CH ₂ group, and each n ₁ is independently 0 or 1.

In the chemical formula of formula (5), each Y ₂ is independently an oxygen atom or a CH ₂ group, R3, R4 independently represent a hydrogen atom, an alkyl group or a perfluoroalkyl group having 1 to 12 carbon atoms, at least one Is an alkyl group having 3 or more carbon atoms or a perfluoroalkyl group, and each n ₂ is independently 0 or 1.

  Details of these materials are described in detail in Patent Documents 3 to 6 (Japanese Unexamined Patent Application Publication Nos. 2002-162630, 2003-96034, 2003-267882, and 2004-86184). Has been. For the tetracarboxylic dianhydride constituting the main chain skeleton of the hydrophobic group, various materials such as aliphatic, alicyclic, and aromatic can be used. Specifically, pyromellitic dianhydride, cyclobutane tetracarboxylic dianhydride, cyclohexane tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, and the like. In addition, materials described in detail in Patent Documents 7 to 9 (Japanese Patent Laid-Open Nos. 11-193345, 11-193346, 11-193347) can be used.

  As described above, the polyimide containing the hydrophobic group of the chemical formula shown in the above formulas (1) to (5) may be used alone or may be used by mixing with other materials. However, when mixed and used, considering the heat resistance, solvent resistance, and affinity, the material to be mixed is also preferably a polyimide resin.

  Moreover, the polyimide containing the hydrophobic group which is not shown by the chemical formula of said formula (1)-(5) can also be used. Specifically, it is a polyimide resin containing an aromatic diamine residue having a linear alkyl chain described in Patent Document 10 (Japanese Patent No. 3097702).

  In view of the fact that the film forming process can be performed at a lower temperature, the polymer material having a hydrophobic group in the side chain preferably includes a soluble polyimide resin. Here, the soluble polyimide resin is a polyimide resin soluble in a solvent. The soluble polyimide resin is obtained by subjecting a raw acid dianhydride and a diamine to chemical imidization treatment in advance in a solution. If the polyimide skeleton has a rigid structure, it is difficult to dissolve in a solvent. Therefore, a bulky alicyclic cyclocarboxylic acid dihydrate is generally used as the raw acid dianhydride in order to disturb the crystallinity of the polyimide resin and make it susceptible to solvation.

  It can be inferred from the analysis of characteristic group vibrations based on the infrared absorption spectrum of the polyimide thin film and the measurement of the ultraviolet-visible absorption spectrum as to what kind of acid anhydride the polyimide resin is composed of. In a polyimide thin film having a bulky alicyclic cyclocarboxylic acid dihydrate skeleton, the absorption edge wavelength is 300 nm or less. For details, see Non-Patent Document 1 ["Latest Polyimides-Fundamentals and Applications-" (edited by Ikuo Imai, Rikio Yokota, editor of Japan Polyimide Research Association, published by NTS Corporation, 2002)] Reference 2 ["Development of new polyimide for high-functional electronics and electronic materials for the next generation and technology for imparting high functionality" (published by Technical Information Association, Inc., 2003)] describes.

  Since the polyimide resin is dissolved in the solvent, the soluble polyimide resin can be formed at a temperature at which the solvent is evaporated, that is, at a low temperature of 200 ° C. or lower. In addition, unreacted polyamic acid and acid anhydrides of side reaction products do not remain in the polyimide thin film, and problems such as poor electrical characteristics of the polyimide film due to these impurities are unlikely to occur.

  In addition, the soluble polyimide resin is not soluble in any solvent, and is only soluble in a specific highly polar solvent such as γ-butyllactone, N-methylpyrrolidone, N, N-dimethylacetamide and the like. Therefore, when forming the semiconductor layer 6 on the wettability changing layer 2, if a low polarity solvent such as toluene, xylene, acetone or isopropyl alcohol is used, the thin film containing the soluble polyimide resin is eroded by the solvent. Never happen.

  In the case where the wettability changing layer 2 is composed of two or more kinds of materials, it is desirable that materials other than the soluble polyimide resin having a hydrophobic group in the side chain are also composed of soluble materials. As a result, the film can be formed at a low temperature. Furthermore, it is desirable that the material has good compatibility with the soluble polyimide resin. A material exhibiting good compatibility with a soluble polyimide resin is less likely to cause phase separation in a solvent and is optimal for a film forming process. The soluble material does not need to be an organic material, and a compound of an organic material and an inorganic material can be used. Examples thereof include phenol resins such as polyvinylphenol, melamine resins, polysaccharides such as pullulan subjected to acetylation treatment, silsesquioxane, and the like. In addition, it is preferable in view of heat resistance, solvent resistance, and affinity that materials other than the soluble polyimide resin having a hydrophobic group in the side chain are also made of a soluble polyimide resin.

  The hydrophobic group of the soluble polyimide resin having a hydrophobic group in the side chain used in the present embodiment can have, for example, a structure represented by the following chemical formula (6).

In the formula, ^{R 1} is an alkyl group, a haloalkyl group or a halogen atom having 1 to 12 carbon atoms having 1 to 12 carbon atoms, X, Y independently of one another in the following formula 7 Chemical formula of (a) ~ (d) And a is an integer of 1 to 5.

  Details of this material are described in, for example, Japanese Patent Application Laid-Open No. 9-272740. Moreover, it is also possible to make the polyimide resin made of the material represented by the chemical formulas of the above formulas (1) to (5) soluble in a solvent by an appropriate chemical treatment. A method of using these materials as a soluble polyimide resin is described in Patent Document 12 (International Publication WO01 / 000732).

  In addition, although the example of the diamine compound which gives the residue which has a side chain group was given above, the tetracarboxylic acid which is another raw material can also give the residue which has a side chain group.

  As another effect when the side chain R having a hydrophobic group is arranged on the surface (see FIG. 9), the interface characteristics with the semiconductor layer 6 in contact with the side chain R can be improved. When the semiconductor layer 6 is made of an organic semiconductor, the effect is more remarkable. Good interface properties include: a. If the semiconductor is crystalline, the crystal grains become larger and the mobility increases; b. If the semiconductor is amorphous (polymer), the interface state density decreases and the mobility increases; c. When the semiconductor is a polymer and has a side chain such as a long-chain alkyl group, the orientation of the semiconductor is regulated so that the molecular axes of the π-conjugated main chain can be arranged in almost one direction, and the mobility is This refers to the appearance of a phenomenon such as an increase.

  The thickness of the wettability changing layer 2 in the present embodiment is preferably 30 nm to 3 μm, and more preferably 50 nm to 1 μm. If it is thinner than this, properties (insulating properties, gas barrier properties, moisture resistance, etc.) as a bulk body are impaired, and if it is thicker than this, the surface shape deteriorates, which is not preferable.

  As a method for imparting energy to a part of the wettability changing layer 2, a. Can be operated in air; b. High resolution is obtained, c. It is preferable to use ultraviolet irradiation from the viewpoint of little damage to the inside of the layer.

  As a method for applying the nanometal ink 11 to the surface of the wettability changing layer 2, various coating methods such as a spin coating method, a dip coating method, a screen printing method, an offset printing method, and an ink jet method can be used. In order to be easily affected by the surface energy of the change layer 2, an ink jet method capable of supplying smaller droplets is particularly preferable. When a normal inkjet head is used, the resolution of the inkjet method is 30 μm and the alignment accuracy is about ± 15 μm. However, by using the difference in surface energy in the wettability changing layer 2, a finer pattern can be formed. It becomes possible to form.

  FIG. 10 shows a transistor (electronic element) created using the laminated structure 1, where FIG. 10A is a plan view and FIG. 10B is a cross-sectional view. In the transistor 41, the gate electrode 42 is formed on the first wettability changing layer 2 b provided on the substrate 7, and the second wettability changing layer 2 c serving also as a gate insulating film is formed so as to cover the gate electrode 42. Is provided. On the second wettability changing layer 2c, the source electrode 5a and the drain electrode 5b are formed in pairs, and the semiconductor layer 6 is formed so as to cover the channel region therebetween. By applying the above method to the formation of the gate electrode 42 and the source / drain electrodes 5a and 5b, good transistor characteristics can be obtained.

  Below, the manufacturing method of the laminated structure 1 is demonstrated. FIG. 11 is a process diagram showing an example of a manufacturing process of the laminated structure 1 of the present embodiment. First, as shown in FIG. 11A, the wettability changing layer 2 is formed on a substrate 7 made of plastic such as glass, polycarbonate, polyarylate, polyether sulfone, silicon wafer, metal or the like. The wettability changing layer 2 is made of a material whose critical surface tension increases upon irradiation with ultraviolet rays and changes from low surface energy (lyophobic) to high surface energy (lyophilic). The preferred structure is as described above. A wettability changing layer 2 is formed by applying a solution obtained by dissolving or dispersing this material in an organic solvent or the like onto the substrate 7 by spin coating, dip coating, wire bar coating, casting, or the like and heating. be able to. Specific examples of the solution include vertical alignment agents for liquid crystal display devices (for example, PIA-X491-E01 manufactured by Chisso, SE-1211 manufactured by Nissan Chemical, JALS-2021 manufactured by JSR, etc.).

  Next, as shown in FIG. 11B, the surface of the wettability changing layer 2 is irradiated with ultraviolet rays through a mask 8. Thereby, the pattern which consists of the high surface energy part 3 and the low surface energy part 4 is formed. As ultraviolet rays, it is desirable to include light having a relatively short wavelength of, for example, 100 nm to 300 nm.

  Next, as shown in FIG. 11C, when a liquid containing a conductive material is supplied onto the wettability changing layer 2 on which the pattern is formed using the ink jet apparatus shown in FIG. The conductive layer 5 is formed only on the energy part 3. Here, the application | coating by the inkjet method is demonstrated. FIG. 12 is a configuration diagram illustrating an example of an inkjet apparatus that performs application (printing) by an inkjet method. The ink jet device 100 includes a surface plate 101, a stage 102, an ink jet head 103, an X axis direction moving mechanism 104 connected to the ink jet head 103, a Y axis direction moving mechanism 105 connected to the stage, and a control device 106. It has.

  The stage 102 supports the substrate 7 that is a target for supplying a liquid containing a conductive material, that is, wiring pattern ink (also referred to as “functional material-containing ink” or “functional liquid”), using the inkjet device 100. Although it is provided for the purpose, it is provided with a fixing mechanism for the substrate 7 such as a suction mechanism (not shown in the figure). Further, a heat treatment mechanism for drying the solvent of the functional liquid applied on the substrate 7 may be provided.

  The inkjet head 103 is a head that includes a plurality of ejection nozzles (not shown), and the plurality of ejection nozzles are arranged on the lower surface of the inkjet head 103 at regular intervals in the X-axis direction. The functional material-containing ink is discharged from the discharge nozzle onto the substrate 7 supported by the stage 102. As a droplet discharge mechanism of the inkjet head 103, for example, a piezo method or the like is conceivable. In this case, a droplet is discharged by applying a voltage to a piezo element in the inkjet head 103 connected to the control device.

  The X-axis direction moving mechanism 104 includes an X-axis direction drive shaft 107 and an X-axis direction drive motor 108 in FIG. The X-axis direction drive motor 108 is a stepping motor or the like. When a drive signal in the X-axis direction is supplied from the control device 106, the X-axis drive shaft 107 is operated, and the inkjet head 103 moves in the X-axis direction.

  The Y-axis direction moving mechanism 105 orthogonal to the X-axis in a plane is composed of a Y-axis direction drive shaft 109 and a Y-axis direction drive motor 110. When a drive signal in the X-axis direction is supplied from the control device 106, the stage 102 moves in the Y-axis direction.

  The control device 106 supplies a discharge control signal to the inkjet head 103. In addition, the control device 106 supplies an X-axis direction drive signal to the X-axis direction drive motor 108 and supplies a Y-axis direction drive signal to the Y-axis direction drive motor 110. The X-axis direction moving mechanism 104 and the Y-axis direction moving mechanism 105 may have a structure using a linear motor. The control device 106 is electrically connected to the inkjet head 103, the X-axis direction drive motor 108, and the Y-axis direction drive motor 110, but the wiring is not shown.

  When the substrate 7 is fixed at a predetermined position on the stage 102, the ink jet apparatus 100 causes the ink jet head 103 and the stage 102 to relatively scan by numerical control with reference to the set print start position on the stage 102. However, the droplets of the functional material-containing ink are ejected from the inkjet head 103 to the high surface energy portion 3 of the substrate 7.

  A Z-axis direction moving mechanism that operates independently of the X-axis direction moving mechanism 104 may be provided between the inkjet head 103 and the X-axis direction moving mechanism 104. By moving the inkjet head 103 in the Z-axis direction, the distance between the substrate 7 and the discharge nozzle surface can be arbitrarily adjusted. A rotation mechanism that operates independently of the Y-axis direction moving mechanism 105 may be provided between the stage 102 and the Y-axis direction moving mechanism 105. By operating the rotation mechanism, it is possible to discharge droplets onto the substrate 7 in a state where the substrate 7 fixed on the stage 102 is rotated at an arbitrary angle.

  Finally, as shown in FIG. 11 (d), a solution in which a low molecular semiconductor is vapor-deposited or a polymer semiconductor or a precursor thereof is dissolved is used, for example, by spin coating, dip coating, wire bar coating, or casting. The semiconductor layer 6 is formed by application and the like with heating. The laminated structure 1 can be manufactured through the above steps.

  Next, a transistor element array substrate which is an embodiment of the electronic element according to the present invention will be described. FIG. 13 shows the configuration of the transistor element array substrate 200. FIG. 13A is a top view, and FIG. 13B is a cross-sectional view taken along the line A-A ′. The transistor element array substrate 200 is a TFT (Thin Film Transistor). Here, an example is shown in which both the gate electrode layer and the source / drain electrode layer are formed on the wettability changing layer.

  First, an electrode layer to be the gate electrode 42 is formed on the first wettability changing layer 2 b provided on the substrate 7. Next, a second wettability changing layer 2c that also serves as a gate insulating film is formed, and electrode layers to be the source electrode 5a and the drain electrode 5b are formed thereon. When forming the electrode layer (gate electrode 42, source / drain electrodes 5a, 5b), as described above, after applying the nanometal ink, it is dried to form a film, and non-volatile such as a dispersion stabilizer in the applied film. After removing the components by a method such as high energy ray irradiation treatment, UV ozone treatment, plasma treatment, solvent cleaning treatment, etc., the conductive film is formed by baking in the atmosphere.

  The gate electrode 42 is connected to the bus line to be driven by the driver IC for scanning signal, and similarly, the source electrode 5a is also connected to the bus line to be driven by the driver for data signal.

  Next, the transistor layer array substrate 200 is completed by forming the semiconductor layer 6 in an island shape including a channel region by, for example, a microcontact printing method. The microcontact printing method is a method in which a PDMS (polydimethylsiloxane) stamp is produced using a master patterned by photolithography, a liquid containing a semiconductor material is attached to the convex portion, and transferred to a substrate. . Since the semiconductor layer is formed in an island shape including the channel region, current leakage to an adjacent element portion does not occur.

  If necessary, the transistor element array substrate 200 is made of a passivation film (e.g., aluminum nitride, silicon nitride, silicon nitride oxide) in order to prevent deterioration of the characteristics of the electronic element (TFT) due to oxygen, moisture, radiation, or the like. It is desirable to coat with (not shown).

  The display device according to the present invention is configured by stacking display elements on the transistor element array substrate 200. Examples of the display element of the present invention include a display element using liquid crystal such as TN, STN, guest-host type, polymer-dispersed liquid crystal (PDLC). As the display element, an electrophoretic element that performs display by moving colored particles sealed in a cell or a microcapsule can also be suitably used (see FIG. 14; described later).

EXAMPLES Next, although an Example is given and this invention is demonstrated in more detail, this invention is not restrict | limited to a following example.
<Example 1>
A silver nanometal ink based on a polar solvent was spin coated on a glass substrate. After drying in an oven at 100 ° C., the substrate was immersed in ethanol for 5 minutes and then dried. Finally, baking was performed in an oven at 160 ° C. in an air atmosphere.

<Comparative Example 1>
In the same manner as in Examples, a polar solvent-based silver nanometal ink was spin-coated on a glass substrate, dried in an oven at 100 ° C., and baked in an oven at 160 ° C. in the air atmosphere.

  When the specific resistance of the spin coat film of Example 1 and Comparative Example 1 was measured by the 4-probe method, the specific resistance of the film of Example 1 was 10 μΩ · cm, whereas the specific resistance of the film of Comparative Example 1 was Resistance was not measurable (100 Ω · cm or more). From the above, it was possible to suppress the specific resistance even when the firing temperature was lowered by the treatment (baking in ethanol) before firing in Example 1.

<Example 2>
Using the method shown in FIG. 11, a transistor having the same structure as that shown in FIG. 10 was formed as follows. On a glass substrate, a mixed solution in which a precursor which becomes a structure represented by the following structural formula (8) and the following structural formula (9) after firing is applied by a spin coating method and fired at 280 ° C. A film wettability changing layer (hereinafter sometimes referred to as “wetting control film”) was provided.

[Where n means an integer of 1 or more]

[Where n means an integer of 1 or more]

  A silver nanometal ink based on a polar solvent was applied to the exposed portion using an inkjet apparatus having the same configuration as in FIG. 12, dried in an oven at 100 ° C., and then subjected to UV ozone treatment for 5 minutes. Thereafter, baking was performed in an oven at 160 ° C. in an air atmosphere to form a first electrode layer (gate electrode).

  Next, a polyimide resin was spin-coated on the electrode layer (gate electrode), and this was baked to form an insulating film, and then a wettability control film similar to the above was formed. The total film thickness of the polyimide insulating film and the wettability control film was 500 nm. A mask was placed so that the wettability pattern to be formed intersected with the first layer pattern, and ultraviolet rays were applied to form a second layer wettability pattern. The second layer wettability pattern is coated with a silver nanometal ink by an ink jet method, dried, treated with UV ozone for 5 minutes, and then baked in an oven at 160 ° C. in an air atmosphere to form a second electrode layer (source Electrode and drain electrode).

  Finally, a solution obtained by dissolving polymer 1 which is an organic semiconductor synthesized by a scheme as shown in the following chemical formula (10) in toluene was applied by spin coating and dried to form a semiconductor layer.

[N means an integer of 1 or more]

<Comparative example 2>
A transistor was manufactured in the same manner as in Example 2. However, baking was performed at 160 ° C. in an air atmosphere oven without performing the UV ozone treatment after drying the silver nanometal ink.

  When the characteristics of the transistors manufactured in Example 2 and Comparative Example 2 were measured, the device manufactured in Example 2 operated as a transistor, but the device manufactured in Comparative Example 2 had a high resistance between the source and the drain. The ON current was extremely small, and substantially no transistor operation was exhibited.

<Example 3>
A transistor was manufactured in the same manner as in Example 2. However, instead of the UV ozone treatment after the silver nanometal ink was dried, the substrate was subjected to a plasma treatment using oxygen as a reactive gas for 5 minutes, and then was performed in an atmosphere atmosphere oven. Firing was performed at 0 ° C. When the characteristics of the manufactured transistor were measured, the operation was as good as in Example 2.

<Example 4>
A transistor element array substrate 200 having the same configuration as that shown in FIG. 13 was manufactured in the same manner as in Example 2. Next, an electrophoretic element was attached to the substrate to manufacture the display device 300. Specifically, as shown in FIG. 14, in the electrophoretic device, microcapsules 51 containing titanium oxide particles 51a and isopar 51b colored with oil blue were mixed with PVA aqueous solution 54 to form transparent electrode 53 made of ITO. A layer composed of the microcapsule 51 and the PVA binder 54 was formed by coating on the polycarbonate substrate 52. This substrate and the transistor element array substrate 200 were laminated to form the display device 300.

  When the display device 300 was operated by inputting a signal to each electrode, all the pixels showed good transistor characteristics, and thus a good image could be displayed.

  Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications can be made.

DESCRIPTION OF SYMBOLS 1 Laminated structure 2 Wetting change layer 3 High surface energy part 4 Low surface energy part 5 Conductive layer 6 Semiconductor layer 11 Nano metal ink 12 Dispersion stabilizer 13 Metal fine particle 14 Vehicle 15 Non-volatile component 16 Metal fine particle coating film 17 Metal fine particle layer 18 Metal conductive film 71 First material 72 Second material 200 Transistor element array substrate 300 Display device

JP-A-2005-310962 JP 2006-26602 A JP 2002-162630 A JP 2003-96034 A JP 2003-267982 A JP 2004-86184 A JP 11-193345 A JP-A-11-193346 JP-A-11-193347 Japanese Patent No. 3097702 JP-A-9-272740 International Publication WO01 / 000732

“Latest Polyimides-Fundamentals and Applications-” (Ikuo Imai, Rikio Yokota, edited by Japan Polyimide Research Association, published by NTS Corporation, 2002) "Development of new polyimide and technology for high functionality for next-generation electronics and electronic materials" (published by Technical Information Association, 2003)

Claims (9)

A method of manufacturing a wiring board in which a wiring made of a conductive layer is formed on a substrate,
Applying an ink containing fine metal particles having a dispersion stabilizer on the surface onto the substrate or an arbitrary layer on the substrate;
Removing a solvent component in the ink to form a metal fine particle coating film;
Removing at least a portion of the dispersion stabilizer contained in the metal fine particle coating film;
Forming the conductive layer by heating and firing the fine metal particle coating film from which the dispersion stabilizer has been removed; and
A method of manufacturing a wiring board, comprising:   2. The method of manufacturing a wiring board according to claim 1, wherein the metal fine particles are gold, silver, palladium, platinum, rhodium, ruthenium, iridium, or an alloy thereof. The substrate includes a material whose surface energy is changed by application of energy, and has at least two portions having different surface energies, ie, a high surface energy portion having a large surface energy and a low surface energy portion having a small surface energy. It has a wettability change layer,
The method for manufacturing a wiring board according to claim 1, wherein the ink is applied to a high surface energy portion of the wettability changing layer.   The method for manufacturing a wiring board according to any one of claims 1 to 3, wherein the dispersion stabilizer is removed by an ultraviolet irradiation treatment.   The method for manufacturing a wiring board according to any one of claims 1 to 3, wherein the dispersion stabilizer is removed by UV ozone treatment.   The method for manufacturing a wiring board according to any one of claims 1 to 3, wherein the dispersion stabilizer is removed by plasma treatment.   The method for manufacturing a wiring board according to claim 1, wherein the dispersion stabilizer is removed by a cleaning process using a solvent.   An electronic device comprising a wiring board manufactured by the method for manufacturing a wiring board according to claim 1.   A display device comprising the electronic element according to claim 8 and a display element.