JP2006261535A - Lamination structure, electronic element using the same, electronic element array using electronic element, manufacturing method of lamination structure, and manufacturing method of electronic element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lamination structure capable of simply forming a minute pattern and including a high value added function in addition to the pattern formation. <P>SOLUTION: The lamination structure 1 contains a material whose critical surface tension changes through the provision of energy to the material, and is provided with a wettability change layer 2 including at least two parts whose critical surface tension differs such as a high surface energy section 3 wherein the critical surface tension is relatively high, and a low surface energy section 4 wherein the critical surface tension is relatively low; a conductive layer 5 formed to the high surface energy section 3 of the wettability change layer 2; and a semiconductor layer 6 provided at least in tangent to the low surface energy section 4 of the wettability change layer 2. Then the wettability change layer 2 is made of a high polymer material containing a halide. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a multilayer structure suitable for a thin film transistor (TFT), an electronic element using the multilayer structure, an electronic element array using the electronic element, a method for manufacturing the multilayer structure, and a method for manufacturing the electronic element It is about.

  Flat panel displays such as liquid crystal display devices, plasma display panels (PDPs), and organic EL (Electro Luminescence) displays are electrodes, active elements such as MIM (Metal-Insulator-Metal) elements, TFTs, and light-emitting elements. A portion configured by patterning the thin film layer is provided.

  In particular, in recent years, an element using an organic material for a part or all of the device has been attracting attention because of its merit in manufacturing such as cost reduction and easy area enlargement, and the possibility of function not found in inorganic materials. For example, according to Patent Document 1, a field effect transistor using an organic semiconductor material whose carrier mobility is changed by a physical external stimulus such as light or heat is proposed.

  On the other hand, a photolithography method is generally used as a method for patterning the thin film layer. The process is as follows.

(1) Coating a photoresist layer on a substrate having a thin film layer (resist coating)
(2) Remove the solvent by heating (pre-bake)
(3) Irradiate ultraviolet light through a hard mask drawn using a laser or electron beam according to pattern data (exposure)
(4) Remove resist in exposed area with alkaline solution (development)
(5) Curing unexposed portion (pattern portion) resist by heating (post-baking)
(6) Immersion in etching solution or exposure to etching gas to remove the thin film layer where there is no resist (etching)
(7) Remove resist with alkaline solution or oxygen radical (resist stripping)
After forming each thin film layer, an active element is completed by repeating the steps (1) to (7). However, expensive equipment and the length of the steps increase the cost.

  In recent years, pattern formation by a printing method has been attempted in order to reduce manufacturing costs. Patent Document 2 discloses a method in which a part of a patterning process of a thin film layer constituting a TFT is performed by, for example, an intaglio offset printing method instead of a photolithography method. FIG. 14 is a conceptual diagram of the intaglio offset printing method. Referring to FIG. 14, resist 102 is placed in the concave portion of printing plate 101 (see FIG. 14A), and transfer body 103 rotates on printing plate 101 containing resist 102 to remove resist 102. It transfers to the transfer body 103 (refer FIG.14 (b)). By printing this on the substrate 104 on which the transfer layer (thin film layer) 105 is formed, a resist pattern is formed on the transfer layer (thin film layer) 105 (see FIG. 14C).

  As described above, the intaglio offset printing method transfers the resist 102 arranged in a predetermined pattern to a rotating body, and prints the transferred resist 102 on the transferred layer 105 from the predetermined pattern on the substrate 104. This is a method of forming a resist 102.

  Non-Patent Document 1 describes a method of forming a metal wiring having a width of about 50 μm and a pitch of about 400 μm by an inkjet method using nanoparticle ink.

  FIG. 15 is a cross-sectional view illustrating a configuration example of a TFT. According to Non-Patent Document 2, as shown in FIG. 15, the electrode layers (gate electrode layer 110, source electrode layer 111, drain electrode layer 112) of TFTs in which all layers are made of organic materials are patterned by an ink jet method. A method of forming is described. Here, ribs 113 made of a hydrophobic material (polyimide) are provided on a glass substrate 114 to form source / drain electrode layers 111 and 112 having an interelectrode gap (channel length) of 5 to 10 μm. Note that the semiconductor layer 115 and the polymer insulator layer 116 are sequentially stacked over the source electrode 111 and the drain electrode 112.

  FIG. 16 is a cross-sectional view showing a method for forming a conductive film pattern. According to Patent Document 3, as shown in FIG. 16, an organic molecular film 122 on a substrate 121 is used to decompose and remove a part thereof by ultraviolet rays or the like, thereby comprising a lyophilic portion 121a and a lyophobic portion 121b. A method of forming a conductive film pattern by forming a pattern, selectively applying a liquid 123 containing conductive fine particles to the lyophilic portion 121a, and then performing heat treatment is disclosed.

According to this method, the pattern consisting of the lyophilic portion 121a and the lyophobic portion 121b can be formed simply by irradiating the organic molecular film 122 with ultraviolet light through a photomask, thereby greatly reducing the process. Can do.
JP-A-7-86600 JP 2002-268585 A JP 2002-164635 A SOCIETY FOR INFORMATION DISPLAY 2002 INTERNATIONAL SYMPOSIUM DIGEST OF TECHNICAL PAPER / VolumeXXXIII, p.753-755. SOCIETY FOR INFORMATION DISPLAY 2002 INTERNATIONAL SYMPOSIUM DIGEST OF TECHNICAL PAPER, VolumeXXXIII, p.1017-1019, Siencce 290, p.2123-2126 (2000).

  However, in the offset printing method as in Patent Document 1, even if an extremely accurate method is used, the pattern error that combines the pattern dimension accuracy and the alignment accuracy is ± 10 μm, and the general-purpose one can reach ± 50 μm. It is not suitable for forming a fine pattern.

  In Non-Patent Document 1, when a normal inkjet head of a level used in a printer is used, the resolution is 30 μm and the alignment accuracy is about ± 15 μm, so that it is difficult to form a fine pattern.

  Non-Patent Document 2 is excellent in that the wettability with respect to ink is controlled by controlling the surface energy to enable pattern formation exceeding the resolution of the ink jet method, but a rib made of polyimide is produced. Therefore, the following long process is required.

(A) Applying polyimide precursor and firing (polyimide film formation)
(B) Apply photoresist layer (resist coating)
(C) Remove the solvent by heating (pre-bake)
(D) Irradiate ultraviolet light through a mask (exposure)
(E) Remove resist in exposed area with alkaline solution (development)
(F) Curing the resist of the unexposed part (pattern part) by heating (post bake)
(G) Remove the resist-free polyimide film with oxygen plasma (etching)
(H) Remove resist with solvent (resist stripping)
Therefore, the advantages of the inkjet method are impaired.

  In the case of Patent Document 3, since the organic molecular film 122 is very thin and the lyophilic portion 121a does not exist and the substrate 121 is exposed, the organic molecular film 122 is other than surface energy control. It does not have a function as a bulk body and has low functionality.

  Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to provide a multilayer structure capable of easily forming a fine pattern and having a high value-added function other than pattern formation. Is to provide a body.

  Another object of the present invention is to provide an electronic device including a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation.

  Furthermore, another object of the present invention is to provide an electronic element array including a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation. .

  Furthermore, another object of the present invention is to provide a method for producing a laminated structure which can easily form a fine pattern and has a high value-added function other than pattern formation.

  Furthermore, another object of the present invention is to provide a method for manufacturing an electronic device having a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation. It is.

  According to this invention, the laminated structure includes a wettability changing layer, a conductive layer, and a semiconductor layer. The wettability changing layer includes a material whose critical surface tension is changed by applying energy, and has at least a critical surface of a high surface energy portion having a relatively large critical surface tension and a low surface energy portion having a relatively small critical surface tension. It has two parts with different tensions. The conductive layer is formed on the high surface energy portion of the wettability changing layer. The semiconductor layer is provided at least in contact with the low surface energy portion of the wettability changing layer. The wettability changing layer is made of a polymer material containing a halide.

  Preferably, the wettability changing layer is made of a paraxylylene compound.

  Preferably, the semiconductor layer is made of an organic semiconductor.

  Preferably, the critical surface tension of the wettability changing layer changes upon irradiation with ultraviolet rays.

  Moreover, according to this invention, an electronic element is provided with the laminated structure of any one of Claims 1-4.

  Preferably, the electronic device further includes an insulator layer and a first electrode layer. The insulator layer is formed at least in contact with the semiconductor layer. The first electrode layer is provided in contact with the insulator layer. The semiconductor layer is formed on the wettability changing layer. The conductive layer includes a pair of second electrode layers provided in contact with the semiconductor layer.

  Preferably, the electronic device further includes a first electrode layer. The wettability changing layer is provided on the first electrode layer. The semiconductor layer is formed on the wettability changing layer. The conductive layer includes a pair of second electrode layers provided in contact with the semiconductor layer.

  Furthermore, according to the present invention, the electronic element array includes a plurality of electronic elements disposed on the substrate. Each of the plurality of electronic elements includes the electronic element according to any one of claims 5 to 7.

  Furthermore, according to this invention, the manufacturing method of the laminated structure includes a first step of forming a wettability changing layer including a polymer material containing a halide as a material whose critical surface tension is changed by applying energy; By applying energy to a part of the wettability changing layer, it consists of a low surface energy part with a relatively small critical surface tension and a high surface energy part with a relatively large critical surface tension, and different critical surface tensions. A second step of forming a patterned pattern, a third step of applying a liquid containing a conductive material to the surface of the wettability changing layer on which the pattern is formed to form a conductive layer in a high surface energy portion, And a fourth step of forming a semiconductor layer on the wettability changing layer.

  Preferably, the method of applying a liquid containing a conductive material to the surface of the wettability changing layer is an ink jet method.

  Preferably, the critical surface tension of the wettability changing layer changes upon irradiation with ultraviolet rays.

  Furthermore, according to this invention, the manufacturing method of an electronic device is the manufacturing method of an electronic device according to claim 6 or claim 7, wherein energy is applied to a part of the wettability changing layer to reduce the surface energy. A first step of forming a pattern consisting of a portion and a high surface energy portion and having different critical surface tensions, and applying a liquid containing a conductive material to the surface of the wettability changing layer on which the pattern is formed Thus, a second step of forming a pair of second electrode layers on the high surface energy part and a third step of forming a semiconductor layer on the wettability changing layer are provided.

  Preferably, the method of applying a liquid containing a conductive material to the surface of the wettability changing layer is an ink jet method.

  Preferably, the critical surface tension of the wettability changing layer changes upon irradiation with ultraviolet rays.

  In the laminated structure according to the present invention, a polymer material containing a halide is used as the wettability changing layer. As a result, the conductive layer is accurately arranged on the wettability changing layer due to the high hydrophobicity of the halide.

  Therefore, according to the present invention, a fine conductive layer can be formed.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Laminated structure]
A laminated structure according to an embodiment of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing an example of the basic configuration of a laminated structure according to an embodiment of the present invention. Referring to FIG. 1, a laminated structure 1 according to an embodiment of the present invention includes a wettability changing layer 2, a conductive layer 5, and a semiconductor layer 6.

  For example, the wettability changing layer 2 is formed on a substrate (not shown). The wettability changing layer 2 is a layer made of a material whose critical surface tension changes when energy is applied. In the embodiment of the present invention, at least two parts having different critical surface tensions have relative critical surface tensions relative to each other. The high surface energy part 3 is large and the low surface energy part 4 has a relatively small critical surface tension.

  The gap between the two high surface energy portions 3 is set to a minute gap of about 1 to 5 μm, for example. Conductive layers 5 are formed on the high surface energy portions 3 with respect to the wettability changing layer 2, and the semiconductor layer 6 is in contact with at least the low surface energy portions 4 with respect to the wettability changing layer 2. Is provided.

  Here, the conductive layer 5 is preferably a layer obtained by solidifying a liquid containing a conductive material by heating, ultraviolet irradiation or the like. Note that the liquid containing a conductive material refers to any of the following.

(A) a conductive material dissolved in a solvent;
(B) a conductive material precursor or a precursor dissolved in a solvent;
(C) Conductive material particles dispersed in a solvent,
(D) Conductive material precursor particles dispersed in a solvent,
More specifically, conductive particles in which fine metal particles such as Ag, Au, and Ni are dispersed in an organic solvent or water, doped PANI (polyaniline), and PEDOT (polyethylenedioxythiophene) are doped with PSS (polystyrene sulfonic acid). An aqueous solution of a conductive polymer.

 The wettability changing layer 2 is a layer made of a material whose critical surface tension changes by applying energy such as heat, ultraviolet rays, electron beams, and plasma, and has a large change amount of the critical surface tension before and after energy application. Is preferred. In the case of such a material, by applying energy to a part of the wettability changing layer 2 and forming a pattern composed of the high surface energy portion 3 and the low surface energy portion 4 and having different critical surface tension, Since the liquid containing the conductive material easily adheres to the high surface energy part 3 (lyophilic) and hardly adheres to the low surface energy part 4 (lyophobic), it contains the conductive material according to the pattern shape. The liquid to be deposited selectively adheres to the high surface energy part 3 which is lyophilic and solidifies it to form the conductive layer 5.

  Here, the wettability (adhesiveness) of the liquid to the solid surface will be described. FIG. 2 is a schematic diagram when a droplet is in an equilibrium state at a contact angle on a solid surface. Referring to FIG. 2, when the droplet 12 is in an equilibrium state at the contact angle θ on the surface of the solid 11, Young's formula (1) is established.

γ _S = γ _SL + γ _L cos θ (1)
In Equation (1), γ _S is the surface tension of the solid 11, γ _SL is the interface tension between the solid 11 and the liquid (droplet 12), and γ _L is the surface tension of the liquid (droplet 12). It is.

The surface tension is substantially synonymous with the surface energy and has exactly the same value. When cos θ = 1, θ = 0 °, and the liquid (droplet 12) 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 11. γ _C plots the relationship between the surface tension of the liquid (droplet 12) and the contact angle using several types of liquid whose surface tension is known, and the surface tension becomes θ = 0 ° (cos θ = 1). Can be easily determined (Zisman plot). The liquid (droplet 12) is easily wetted on the surface of the solid 11 having a large γ _C (lyophilic) and hardly wet on the surface of the solid 11 having a small γ _C (lyophobic).

It is convenient to measure the contact angle θ by the droplet method. For the droplet method,
(E) A tangent method in which the reading microscope is pointed at the droplet 12 and the cursor line in the microscope is aligned with the contact point of the droplet 12 to read the angle. (F) The cross cursor is aligned with the apex of the droplet 12 and one end is dropped. The θ / 2 method obtained by doubling the angle of the cursor line when matching the point where the sample 12 and the solid 11 sample touch each other (g) The droplet 12 is projected on the monitor screen, and one point on the circumference (preferably a vertex) There is a three-point click method in which the contact point (two points) between the droplet 12 and the solid 11 sample is clicked and processed by a computer. The accuracy increases in the order of (e) → (f) → (g).

FIG. 3 is a surface tension-contact angle characteristic diagram showing the results of performing Zisman plots of the ultraviolet non-irradiated part and the ultraviolet irradiated part when chlorinated polyparaxylylene is used for the wettability changing layer. Referring to FIG. 3, when chlorinated polyparaxylylene is used for wettability changing layer 2, the critical surface tension γ _C of the non-ultraviolet irradiation portion is about 31 mN / m, and the critical surface tension of the ultraviolet irradiation portion is about 31 mN / m. γ _{C ′} is about 52 mN / m, and the difference Δγ _C is about 21 mN / m.

In order to ensure that the liquid containing the conductive material adheres only to the high surface energy part 3 that is lyophilic according to the pattern shape of the high surface energy part 3 and the low surface energy part 4, the surface energy difference is large. In other words, the critical surface tension difference Δγ _C needs to be large.

Table 1 shows that the wettability changing layer 2 made of various materials is formed on a glass substrate, the difference Δγ _{C in} the critical surface tension between the energy imparted part and the unapplied part, and the PEDOT / PSS (aqueous conductive polymer). ) Was evaluated for selective adhesion. Selective adhesion is the PEDOT / PSS adhesion (pattern failure) to the unapplied part after dropping the PEDOT / PSS aqueous solution onto the area including the boundary of the pattern consisting of the energy-applied part and the unapplied part. The presence or absence was observed. In Table 1, A is Marcalinker M (Maruzen Chemical), B is RN-1024 (Nissan Chemical), C is AG-7000 (Asahi Glass), and D is chlorinated polyparaffin. Xylylene.

From Table 1, the difference Δγ _C between the critical surface tension of the low surface energy portion 4 and the critical surface tension of the high surface energy portion 3 of the wettability changing layer 2 is preferably 10 mN / m or more, and 15 mN / m or more. It turns out that it is further desirable.

  By the way, in the laminated structure 1 according to the embodiment of the present invention, since the semiconductor layer 6 is in contact with the low surface energy portion 4 of the wettability changing layer 2, the physical properties of the part affect the characteristics of the semiconductor layer 6. Conceivable.

FIG. 4 is a critical surface tension-mobility characteristic diagram showing the results when the material of the wettability changing layer is changed for the electronic device (TFT). More specifically, FIG. 4 shows that an electronic device (TFT) having a structure of Example 2 to be described later is manufactured by changing the material of the wettability changing layer (gate insulating film) 2 and the mobility is changed to the wettability changing layer. Plotted against critical surface tension γ _{C of} 2 (no energy applied).

In FIG. 4, A is chlorinated polyparaxylylene, B is polyvinylphenol, C is organic silica, D is a thermal oxide film, E is polyimide, F is SiO ₂ (sputtered film). However, the source electrode 5a and the drain electrode 5b were formed by lifting off an Au vapor deposition film.

Referring to FIG. 4, the mobility rapidly decreases when the critical surface tension γ _C exceeds 40 mN / m. From this result, it is desirable that the critical surface tension (γ _C ) of the low surface energy portion of the wettability changing layer 2 is 40 mN / m or less.

If the critical surface tension (γ _C ) is smaller than 20 mN / m, most of the solvent is repelled. Therefore, when the semiconductor layer 6 is formed by coating, the critical surface tension (γ _C ) is 20 mN / m. The above is desirable.

  Moreover, it is desirable to use a polymer material having a hydrophobic group for the wettability changing layer 2. This may have a side chain protruding from the main chain, or a hydrophobic group may be contained in the main chain.

  The “side chain” generally refers to a carbon chain branched from the main chain (Chemical Dictionary (published by Tokyo Kagaku Dojin)), but in this specification, it does not contain carbon like a halide. Also includes groups.

  Specifically, as shown in the conceptual diagram of FIG. 5, 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 and (meth) acrylate. Say what is bound. Further, as shown in the conceptual diagram of FIG. 6, it means that a hydrophobic group R is bonded to the main chain L.

Examples of the hydrophobic group include groups having a terminal structure of —CF ₂ CH ₃ , —CF ₂ CF ₃ , —CF (CF ₃ ) ₂ , —C (CF ₃ ) ₃ , —CF ₂ H, —CFH _{2 and the} like. Can be mentioned. 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. Furthermore, a polyfluoroalkyl group (hereinafter referred to as “Rf group”) in which two or more of the hydrogen atoms of the alkyl group are substituted with fluorine atoms is preferable, and an Rf group having 4 to 20 carbon atoms is particularly preferable. The Rf group having 6 to 12 carbon atoms is preferred. The Rf group may have a linear structure or a branched structure, but a linear structure is preferred. Further, the hydrophobic group is preferably a perfluoroalkyl group in which substantially all of the hydrogen atoms of the alkyl group are substituted with fluorine atoms. Perfluoroalkyl _{group, C n F 2n + 1 -} (n is an integer of 4 to 16) preferably a group represented by, in particular, groups where n is an integer from 6-12 is preferred. Perfluoroalkyl group. It may be a linear structure or a branched structure, and a linear structure is preferred.

  The above materials are described in detail in JP-A-3-178478 and the like, and have the property of becoming lyophilic when brought into contact with a liquid or solid in a heated state and becoming lyophobic when heated in air. That is, the critical surface tension can be changed by selecting a contact medium and applying thermal energy.

Furthermore, examples of the hydrophobic group include groups having a terminal structure such as —CH ₂ CH ₃ , —CH (CH ₃ ) ₂ , and —C (CH ₃ ) ₃ that do not contain a fluorine atom. 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 hydrophobic group may have a linear structure or a branched structure, but a linear structure is preferred.

  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. It is considered that, due to ultraviolet irradiation or the like, a part of the bond is cut or the orientation state changes, so that the critical surface tension increases and becomes lyophilic.

  Furthermore, examples of the hydrophobic group include halogens such as a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The bond energy of these halogen atoms and carbon atoms is, for example, 441 kJ / mol for carbon-fluorine, 328 kJ / mol for carbon-chlorine, 276 kJ / mol for carbon-bromine, and 271 nm, 364 nm, respectively, when converted to the wavelength of light, It is 434 nm, and can be sufficiently cut with the light energy of ultraviolet rays. These are hydrophobic, but are considered to become hydrophilic as a result because the bond is broken by ultraviolet irradiation or the like. In particular, halogenated polyparaxylylene has high insulation, good coverage, and excellent coverage at the edge and corner of the base, so that it is difficult to short-circuit and an insulating film can be formed. Since it can be performed at room temperature, it does not apply thermal stress to the substrate, so that film peeling and voids can be avoided, which is more desirable.

  As another effect that the hydrophobic group is present at the laminated interface with the semiconductor layer, the interface characteristic with the semiconductor layer 6 in contact with the hydrophobic group can be improved. When the semiconductor layer 6 is made of an organic semiconductor, the effect is more remarkable. Good interface characteristics means that (i) when the semiconductor is crystalline, the crystal grains become large and mobility increases, and (ii) when the semiconductor is amorphous (polymer) (Iii) When the semiconductor is a polymer and has a side chain such as a long-chain alkyl group, its orientation is restricted, so that the π-conjugated main This means that the molecular axis of the chain can be arranged in almost one direction, and a phenomenon such as increased mobility appears.

  The thickness of the wettability changing layer 2 in the embodiment of the present invention is preferably in the range of 30 nm to 3 μm, and more preferably in the range of 50 nm to 1 μm. When the wettability changing layer 2 is thinner than the above thickness, the properties as a bulk body (insulation, gas barrier property, moisture resistance, etc.) are impaired, and when the wettability changing layer 2 is thicker than the above thickness, the surface shape is deteriorated. Absent.

  As a method for applying a liquid containing a conductive material 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. However, in order to be easily affected by the surface energy of the wettability changing layer 2, an ink jet method capable of supplying smaller droplets is particularly preferable. As described above, when a normal head of a level used in a printer is used, the resolution of the ink jet method is 30 μm and the alignment accuracy is about ± 15 μm. By utilizing the difference, it becomes possible to form a finer pattern.

  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, polyphenylene vinylene and derivatives thereof, and the like. Use organic semiconductors such as polyphenylene-based conductive polymers, 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 the organic semiconductor is used as described above, the effect of improving the characteristics by the wettability changing layer 2 appears more remarkably.

  In addition, as a method of imparting energy to a part of the wettability changing layer 2, (C1) from the point that it can be operated in the atmosphere, (C2) high resolution is obtained, (C3) the damage to the inside of the layer is small, etc. It is preferable to use ultraviolet irradiation.

[Manufacturing method of laminated structure]
FIG. 7 is a diagram showing a manufacturing process of the laminated structure 1 according to the embodiment of the present invention.

  First, as shown in FIG. 7A, the wettability changing layer 2 is formed on a substrate 7 made of glass, polycarbonate, polyarylate, polyethersulfone or other plastic, 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 of the wettability changing layer 2 is as described above. According to experiments, the polymer composed of a polyparaxylylene skeleton has a particularly large change in wettability due to ultraviolet irradiation. The polymer having such a structure vaporizes and thermally decomposes the precursor, and the generated radicals cause simultaneous reaction of adsorption and polymerization on the substrate 7, whereby the wettability changing layer 2 is formed. Specific examples of the precursor include dimonochloroparaxylylene solid.

  Next, as shown in FIG. 7B, the surface of the wettability changing layer 2 is irradiated with ultraviolet rays through a mask 8. Thereby, the pattern which consists of the low surface energy part 4 and the high surface energy part 3 is formed. It is desirable that the ultraviolet rays include light having a relatively short wavelength of 100 nm to 300 nm.

  Next, as shown in FIG. 7C, when a liquid containing a conductive material is supplied onto the wettability changing layer 2 on which the pattern is formed, for example, by an inkjet method, only the high surface energy portion 3 is supplied. Conductive layer 5 is formed.

  Finally, as shown in FIG. 7 (d), a low molecular semiconductor is vapor-deposited, or a solution in which a polymer semiconductor or a precursor thereof is dissolved is spin-coated, dip-coated, wire bar-coated, cast, etc. The semiconductor layer 6 is formed by applying and heating.

[Electronic element]
Electronic elements such as a diode, a transistor, a photoelectric conversion element, and a thermoelectric conversion element can be formed using the laminated structure 1 having the above-described structure as a part of the constituent elements.

  FIG. 8 is a diagram showing an example of the electronic element 41 in the embodiment of the present invention. The electronic element 41 according to the embodiment of the present invention includes a wettability changing layer 2, a pair of electrode layers 5 a and 5 b, a semiconductor layer 6, a substrate 7, and an electrode layer 42.

  The substrate 7 is made of plastic such as glass, polycarbonate, polyarylate, polyether sulfone, silicon wafer, metal or the like. The electrode layer 42 is formed on the substrate 7 by vapor deposition, CVD, spin coating, dip coating, casting, or the like. The electrode layer 42 is made of various conductive thin films. When the electrode layer 42 is formed, various conductive thin films may be formed on the entire surface and then patterned by a normal photolithography method or a micro contact printing method, or a liquid containing a conductive material may be formed by an inkjet method or the like. You may supply and draw directly.

  When the electrode layer 42 is formed on the substrate 7, the above-described wettability changing layer 2 is formed on the electrode layer 42. Since the wettability changing layer 2 also serves as a gate insulating film, it is desirable that the wettability changing layer 2 be highly insulating.

  The wettability changing layer 42 may have a two-layer structure in which the upper layer is a wettability changing layer and the lower layer is an insulator layer having no wettability changing function but having higher insulating properties.

  When the wettability changing layer 2 is formed, a pattern composed of the low surface energy part 4 and the high surface energy part 3 is formed on the wettability changing layer 2 by the above-described method, and a liquid containing a conductive material is formed thereon. As a result, a pair of electrode layers 5a and 5b are formed as conductive layers on the high surface energy portion 3.

  Finally, the above-described semiconductor layer 6 is formed on the entire surface (or an island shape including at least the channel region).

  As is apparent from FIG. 8, the electronic element 41 functions as a TFT (thin film transistor). That is, the electrode layer 42 is the gate electrode G, the wettability changing layer 2 is the gate insulating film, and the electrode layers 5a and 5b are the source electrode S and the drain electrode D, respectively. The gap between the electrode layers 5a and 5b corresponds to the channel length. Since the wettability changing layer 2 also serves as a gate insulating film, the process is simplified as compared with the configuration example shown in FIG.

  In FIG. 8, a wettability changing layer (not shown) different from the wettability changing layer 2 is provided on the substrate 7 before the electrode layer 42 is formed, and is used for patterning the electrode layer 42. Good.

[Electronic element array]
FIG. 9 is a diagram showing an example of an electronic element array according to the embodiment of the present invention. FIG. 9A is a cross-sectional view of the electronic element array, and FIG. 9B is a plan view showing an arrangement relationship of electrodes and the like. 9 shows an example in which the electronic element 41 of the type shown in FIG. 8 is used.

  An electrode layer 42 serving as a gate electrode, a wettability changing layer 2 also serving as a gate insulating film, an electrode layer 5a serving as a source electrode, and an electrode layer 5b serving as a drain electrode are formed on the substrate 7 in the same manner as shown in FIG. A plurality of patterns are formed by patterning in a two-dimensional array.

  The gate electrode 42 for each TFT (electronic element 41) is connected to a bus line in order to be driven by a scanning signal driver IC. Similarly, the source electrode 5a for each TFT (electronic element 41) is also data. It is connected to the bus line to be driven by a signal driver.

  Next, the semiconductor element 6 is formed in an island shape including a channel region by, for example, a micro contact printing method or a dispenser method, thereby completing an electronic element (TFT) array 51. 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. . When these methods are used, since the semiconductor layer 7 is formed in an island shape including the channel region, no current leaks to adjacent element portions.

  Although not shown in FIG. 9, the electronic element (TFT) 41 is covered with a passivation film in order to prevent the characteristics of the electronic element (TFT) 41 from being deteriorated by oxygen, moisture, radiation, or the like. desirable.

  For example, aluminum nitride, silicon nitride, silicon nitride oxide, or the like can be used for the passivation film. These are formed by a CVD method, an ion plating method, or the like.

[Display device]
FIG. 10 is a cross-sectional view of a display device using the electronic element array 51 shown in FIG. A display element 64 is provided between the substrate 7 of the electronic element (TFT) array 51 and the substrate 63 having the transparent conductive film 62, and the display element on the drain electrode 5b which also serves as a pixel electrode is switched by the TFT (electronic element) 41. Is done. As the substrate 63, plastic such as glass, polyester, polycarbonate, polyarylate, or polyethersulfone can be used. As the display element 64, methods such as liquid crystal, electrophoresis, and organic EL can be used.

  A liquid crystal display element using a liquid crystal as the display element 64 is low in power consumption due to electric field driving, and can be driven at a high driving frequency because of low driving voltage, and is suitable for large-capacity display. Examples of the display method of the liquid crystal display element include TN, STN, guest-host type, polymer-dispersed liquid crystal (PDLC), etc., but PDLC is preferable in that a bright white display can be obtained in a reflective type. .

  In a reflective liquid crystal element or the like in which a display element 64 is laminated on an electronic element (TFT) array 51, an interlayer insulating film 81 is provided on the electronic element (TFT) array 52 as shown in FIG. A pixel electrode 83 provided on the interlayer insulating film 81 through 82 is connected to the drain electrode 5 b of the electronic element (TFT) 41.

  The electrophoretic display element is composed of a dispersion liquid in which particles exhibiting a first color (for example, white) are dispersed in a color dispersion medium exhibiting a second color, and the particles exhibiting the first color are colored and dispersed. By charging in the medium, the position in the dispersion medium can be changed by the action of an electric field, thereby changing the color to be exhibited. According to this display method, it is possible to display brightly and with a wide viewing angle, and since it has a display memory property, it is preferably used particularly from the viewpoint of power consumption.

  By using microcapsules in which the dispersion is wrapped with a polymer film, the display operation is stabilized and the display device can be easily manufactured. Microcapsules can be produced by a known method such as a coacervation method, an In-Situ polymerization method, or an interfacial polymerization method. As the white particles, titanium oxide is particularly preferably used, and surface treatment or compounding with other materials is performed as necessary. Examples of the dispersion medium include aromatic hydrocarbons such as benzene, toluene, xylene, naphthenic hydrocarbons, aliphatic hydrocarbons such as hexane, cyclohexane, kerosene, and paraffinic hydrocarbons, trichloroethylene, tetrachloroethylene, trichlorofluoroethylene, odor It is preferable to use an organic solvent having a high resistivity such as halogenated carbon (hydrocarbon) such as ethyl halide, fluorine-containing ether compound, fluorine-containing ester compound, or silicone oil.

  In order to color the dispersion medium, oil-soluble dyes such as anthraquinones and azo compounds having desired absorption characteristics are used. A surfactant or the like may be added to the dispersion for stabilization of dispersion.

  Since the organic EL element is a self-luminous type, vivid full color display can be performed. Further, since the EL layer is a very thin organic thin film, it has a high flexibility and is particularly suitable for being formed on a flexible substrate.

  Examples that embody the above-described embodiment will be described below together with comparative examples.

[Example 1]
Example 1 relates to fabrication of an electronic device. Here, an electronic element (TFT) 41 having the structure shown in FIG. 8 was produced.

  First, 60 nm-thick aluminum (Al) was vacuum-deposited on the glass substrate 7, and the vacuum-deposited Al was processed into a width of 40 μm by photolithography etching to form the gate electrode 42.

  Next, as the wettability changing layer 2 also serving as a gate insulating film, a dimonochloroparaxylylene solid dimer that becomes a structure represented by the chemical formula of Chemical Formula 1 after film formation is vaporized by a chemical vapor deposition method (CVD method). It was pyrolyzed and formed on the substrate 7.

  In order to evaluate the characteristics of the wettability changing layer 2, the following experiment was separately performed.

Using a UV lamp, adjusting the distance between the light source and the substrate so that the intensity of light at 250 nm is 40 mW / cm ² , changing the irradiation time to change the irradiation amount (for a wavelength of 250 nm), and contact with water A change in angle was observed.

FIG. 11 is a diagram showing the relationship between the UV irradiation amount and the contact angle with water. When not irradiated, the contact angle exceeds 80 ° and is hydrophobic (water repellency). However, when the irradiation dose is 10 J / cm ² or more, the contact angle decreases to about 10 ° and changes to hydrophilicity. It is considered that the amount of irradiation can be further reduced by using a light source adapted to the wavelength of light effective for inducing this change.

The contact angles of several types of liquids having different surface energies were measured when the ultraviolet rays were irradiated at 10 J / cm ² and when they were not irradiated.

  FIG. 3 shows the relationship between the surface tension of the liquid and the contact angle. From FIG. 3, the critical surface tension is about 31 mN / m when not irradiated and about 52 mN / m when irradiated with ultraviolet rays.

Next, a mask provided with a pattern having an opening width of 40 μm and a space between the openings of 5 μm was pressure-bonded to the wettability changing layer 2 and irradiated with ultraviolet rays at 10 J / cm ² .

  Subsequently, an aqueous solution of PEDOT / PPS, which is a conductive polymer, was supplied onto the wettability changing layer 2 using an inkjet method and dried to form the source electrode layer 5a and the drain electrode layer 5b.

  Finally, a solution obtained by dissolving an organic semiconductor polymer 1 synthesized by a scheme shown in the following chemical formula in toluene was applied by a spin coat method and dried to form a semiconductor layer 6.

The mobility of the TFT (electronic element 41) thus manufactured is 2.5 × 10 ⁻³ cm ² / Vs, the On / Off ratio is 1950, and the source electrode layer 5a and the drain electrode layer 5b are It was not inferior to the case where it was formed by lifting off a vapor deposition film of Au.

[Comparative Example 1]
Fabricated in the same manner as in Example 1 except that a thermal oxide film was formed as a gate insulating film on a low-resistance Si substrate, an Au vapor deposition film was patterned by lift-off, and a source electrode layer 5a and a drain electrode layer 5b were formed. did.

The mobility of the TFT manufactured in this manner was 9.8 × 10 ⁻⁵ cm ² / Vs, and the On / Off ratio was 1050. The characteristics were inferior to those of Example 1. It is considered that since the surface of the gate insulating film is hydrophilic, the interface state density is increased by local polarization, and the mobility is decreased.

[Example 2]
After firing, a precursor to be a structure represented by the chemical formulas of Chemical Formula 3 to Chemical Formula 4 was produced on a glass substrate under the same film forming conditions as in Example 1.

Next, the contact angles of several types of liquids having different surface energies were measured before and after UV irradiation at 10 J / cm ² in the same manner as in Example 1, and the critical surface tension was obtained in the same manner as in Example 1. It is shown in 2.

  From Table 2, it can be seen that the critical surface tension is about 27 to 31 mN / m when not irradiated and about 50 to 52 mN / m when irradiated with ultraviolet rays. From this, it can be seen that any material can be used as the material constituting the wettability changing layer 2.

[Example 3]
The material used in Example 2 was produced on a glass substrate under the same film formation conditions as in Example 1. Next, patterning was performed under the same conditions as in Example 1, and a source electrode and a drain electrode were produced by an inkjet method. Subsequently, a semiconductor layer was formed by spin coating using the polymer 1 represented by the chemical formula of Chemical Formula 2 as an organic semiconductor material.

  Table 3 shows the mobility and On / Off ratio results of the TFTs thus fabricated.

  Whichever polyparaxylylene material was used, the same result as in Example 1 using the same organic semiconductor was obtained.

[Example 4]
This embodiment relates to the production of an electronic element array 51 as shown in FIG.

  First, the gate electrode 42 and the wettability changing layer 2 also serving as a gate insulating film were produced in the same manner as in Example 1. The source electrode layer 5a and the drain electrode layer 5b were formed in the same manner as in Example 1 using an aqueous solution of PEDOT / PSS which is a conductive polymer.

  Finally, the semiconductor layer 6 was formed in an island shape with a dispenser using a solution obtained by dissolving the polymer 1 in toluene.

Through the above steps, an electronic element array 51 having 32 × 32 (interelement pitch 500 μm) TFTs (electronic elements 41) in a two-dimensional array on the substrate 7 was produced. The average characteristics of the plurality of TFTs (electronic elements 41) were a mobility of 1.5 × 10 ⁻³ cm ² / Vs and an On / Off ratio of 2000.

[Example 5]
This embodiment relates to the production of a display device 61 using an electronic element array 51 as shown in FIG.

  First, a microcapsule 67 containing titanium oxide particles 65 and isopar 66 colored with oil blue is mixed with a PVA aqueous solution as a display element 64 and applied onto a polycarbonate substrate 63 on which a transparent electrode 62 made of ITO is formed, A layer composed of the microcapsules 67 and the PVA binder 68 was formed. This substrate was bonded to the substrate 7 on which the TFT array (electronic element array 51) produced in Example 4 was formed.

  A driver IC for scanning signals was connected to the bus line connected to the gate electrode 42, and a driver IC for data signals was connected to the bus line connected to the source electrode 5a. When the screen was switched every 0.5 seconds, a good still image could be displayed.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention is applicable to a laminated structure which can easily form a fine pattern and has a high value-added function in addition to pattern formation. In addition, the present invention is applied to an electronic device that can easily form a fine pattern and includes a laminated structure having a high value-added function in addition to pattern formation. Furthermore, the present invention is applied to an electronic element array having a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation. Furthermore, the present invention is applied to a method for manufacturing a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation. Furthermore, the present invention is applied to a method of manufacturing an electronic device including a laminated structure that can easily form a fine pattern and has a high value-added function in addition to pattern formation.

It is a cross-sectional schematic diagram which shows the example of a fundamental structure of the laminated structure by embodiment of this invention. It is a schematic diagram when a droplet is in an equilibrium state at a contact angle on a solid surface. It is a surface tension-contact angle characteristic figure which shows the result of having performed the Zisman plot of the ultraviolet ray non-irradiation part and the ultraviolet irradiation part at the time of using chlorinated polyparaxylylene for a wettability change layer. It is a critical surface tension-mobility characteristic figure which shows the result at the time of producing by changing the material of a wettability change layer regarding an electronic device (TFT). It is a conceptual diagram which shows the polymer material example which has a hydrophobic group in a side chain. It is a conceptual diagram which shows the polymer material example which has a hydrophobic group in a principal chain. It is a figure which shows the preparation process of the laminated structure by embodiment of this invention. It is a figure which shows the example of the electronic element in embodiment of this invention. It is a figure which shows an example of the electronic element array by embodiment of this invention. It is sectional drawing of the display apparatus using the electronic element array shown in FIG. It is a figure which shows the relationship between the ultraviolet irradiation amount and the contact angle with respect to water. It is sectional drawing which shows the other example of a display apparatus. It is sectional drawing which shows another example of a display apparatus. It is a conceptual diagram of the intaglio offset printing method. It is sectional drawing which shows the structural example of TFT. It is sectional drawing which shows the formation method of an electrically conductive film pattern.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Laminated structure, 2 Wetting property change layer, 3 High surface energy part, 4 Low surface energy part, 5 Conductive layer, 5a, 5b A pair of electrode layer, 6 Semiconductor layer, 31 Electronic element, 32 Insulator layer, 33 Electrode Layer, 41 electronic element, 42 electrode layer, 51 electronic element array, 61 display device.

Claims (14)

The material includes a material whose critical surface tension is changed by application of energy, and at least the critical surface tension is different between the high surface energy portion having a relatively large critical surface tension and the low surface energy portion having a relatively small critical surface tension. A wettability changing layer having two sites;
A conductive layer formed on the high surface energy portion of the wettability changing layer;
A semiconductor layer provided at least in contact with the low surface energy portion of the wettability changing layer,
The wettability changing layer is a laminated structure made of a polymer material containing a halide.   The laminated structure according to claim 1, wherein the wettability changing layer is made of a paraxylylene compound.   The stacked structure according to claim 1, wherein the semiconductor layer is made of an organic semiconductor.   The laminated structure according to any one of claims 1 to 3, wherein the wettability changing layer changes the critical surface tension by irradiation with ultraviolet rays.   An electronic element provided with the laminated structure of any one of Claims 1-4. An insulator layer formed at least in contact with the semiconductor layer;
A first electrode layer provided in contact with the insulator layer;
The semiconductor layer is formed on the wettability changing layer,
The electronic device according to claim 5, wherein the conductive layer includes a pair of second electrode layers provided in contact with the semiconductor layer. A first electrode layer;
The wettability changing layer is provided on the first electrode layer;
The semiconductor layer is formed on the wettability changing layer,
The electronic device according to claim 5, wherein the conductive layer includes a pair of second electrode layers provided in contact with the semiconductor layer. Comprising a plurality of electronic elements disposed on a substrate;
Each of these electronic elements is an electronic element array which consists of an electronic element of any one of Claims 5-7. A first step of forming a wettability changing layer containing a polymer material containing a halide as a material whose critical surface tension is changed by applying energy;
The critical surface is composed of a low surface energy part having a relatively small critical surface tension and a high surface energy part having a relatively large critical surface tension by applying energy to a part of the wettability changing layer. A second step of forming patterns with different tensions;
A third step of applying a liquid containing a conductive material to the surface of the wettability changing layer on which the pattern is formed to form a conductive layer on the high surface energy portion;
And a fourth step of forming a semiconductor layer on the wettability changing layer.   The method for producing a laminated structure according to claim 9, wherein a method of applying a liquid containing a conductive material to the surface of the wettability changing layer is an inkjet method.   The method of manufacturing a laminated structure according to claim 9 or 10, wherein the wettability changing layer changes the critical surface tension by ultraviolet irradiation. A method for manufacturing an electronic device, comprising:
The electronic element comprises the electronic element according to claim 6 or claim 7,
The manufacturing method includes:
A first step of forming a pattern comprising the low surface energy part and the high surface energy part by applying energy to a part of the wettability changing layer and having different critical surface tensions;
A second step of forming the pair of second electrode layers on the high surface energy portion by applying a liquid containing a conductive material to the surface of the wettability changing layer on which the pattern is formed;
And a third step of forming a semiconductor layer on the wettability changing layer.   The method for producing an electronic element according to claim 12, wherein a method of applying the liquid containing the conductive material to the surface of the wettability changing layer is an inkjet method.   The method of manufacturing an electronic element according to claim 12 or 13, wherein the wettability changing layer changes the critical surface tension by ultraviolet irradiation.

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