JP2008294341A - Organic thin film transistor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic thin film transistor for which the position accuracy of a semiconductor pattern is improved, an organic semiconductor thin film of high crystallinity with sufficient conductivity is formed and element dispersion is reduced. <P>SOLUTION: For the organic thin film transistor, after forming a pattern area A including a siloxane compound, the organic semiconductor thin film is formed in an area in contact with the pattern area A. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an organic semiconductor thin film and an organic thin film transistor using the same.

  In many electronic devices, various functional thin films are patterned and used. However, even if a crystalline organic thin film is formed by a vacuum deposition method or the like, unique conditions are required or the material used is limited. Or receive. Furthermore, since the organic thin film has low resist resistance, it is difficult to pattern by an ordinary patterning method including a photolithography process and an etching process.

  On the other hand, if a crystalline thin film can be formed by an ink jet method, a patterned crystalline organic thin film, which has been difficult with the prior art, can be easily formed.

  Conventionally, when an organic semiconductor material thin film is formed using a printing method or an ink jet method, a solution in which an organic semiconductor material is dissolved in a solvent is placed on a substrate using a printing method or an ink jet method, and then this placement is performed. Formed by evaporating the solvent from the resulting solution.

  However, when an organic semiconductor material is used to form a crystalline thin film, the coating film is repelled and not reproducible, and the position accuracy and pattern accuracy of semiconductor patterning are poor, resulting in variations in characteristics from device to device. Arise. In addition, there is a problem that a thin film having high crystallinity and sufficient conductivity is not formed and mobility is not sufficient.

  Attempts have been made to improve the wettability and crystallinity of organic semiconductor materials and their solutions by, for example, modifying the surface energy of the gate insulating layer using a surface treatment agent. For example, the thin film formation region on the surface of the silicon substrate is a surface state having a high affinity with the thin film formation material (a self-assembled film having an atomic group common to the molecules constituting the thin film formation material is formed with a silane compound, ) A method of discharging a solution is disclosed (for example, see Patent Document 1).

However, in order to improve the wettability of the organic semiconductor material to the substrate surface and to form a crystallized film (self-assembled film) having sufficient conductivity on the substrate surface having a small surface energy, Surface treatment is insufficient, and reproducibility is still insufficient in terms of repellency, and a thin film having sufficient carrier mobility has not yet been obtained.
JP 2003-234522 A

  Accordingly, an object of the present invention is to form an organic thin film transistor in which the positional accuracy of a semiconductor pattern is improved and an organic semiconductor thin film having sufficient conductivity and high crystallinity is formed to reduce element variation.

  The above object of the present invention is achieved by the following means.

  1. An organic thin film transistor comprising an organic semiconductor thin film formed in a region in contact with the pattern region A after forming a pattern region A containing a siloxane compound.

  2. 2. The organic thin film transistor as described in 1 above, wherein the organic semiconductor thin film is a cast film from an organic semiconductor solution or dispersion.

  3. 3. The organic thin film transistor according to 1 or 2 above, wherein a pattern region A is formed so as to surround a region where the organic semiconductor thin film is formed.

  According to the present invention, it is possible to obtain an organic thin film transistor with good patterning accuracy of the organic semiconductor thin film and reduced variation.

  The best mode for carrying out the present invention will be described below.

  In the present invention, a siloxane compound is included when an organic semiconductor material solution or dispersion is applied onto a substrate by a coating method such as a printing method or an ink jet method to form a cast film and an organic semiconductor thin film. A pattern region A is formed, and then an organic semiconductor material solution or a dispersion is supplied to a region in contact with the pattern region A.

  Examples of the substrate on which the organic semiconductor thin film according to the present invention is formed include a substrate having a surface having a thin film layer made of a metal oxide such as silicon oxide or titanium oxide, which is often used as an insulating film, such as glass or plastic substrate. There is. Examples of the thin film transistor (TFT) according to the present invention include a silicon substrate having a thermal oxide film and a substrate having a metal oxide thin film used for a gate insulating film.

  In the formation of the pattern region A containing the siloxane compound, since the siloxane compound repels the organic semiconductor material solution, even if the organic semiconductor material solution is applied including this region, the droplets are repelled from this region. In the pattern region A, no organic semiconductor thin film is formed. The droplets repelled in the pattern area A naturally gather in adjacent areas to form an organic semiconductor thin film there. That is, the positional accuracy of cast film formation can be improved by patterning with a siloxane compound.

  Specifically, the pattern region A containing a siloxane compound is a region provided with a layer containing a siloxane compound shown below.

  For the layer containing the siloxane compound of the present invention, any of low molecules, oligomers and polymers having a siloxane structure can be used, but from the viewpoint of film forming properties, polysiloxane compounds, so-called silicone rubbers are preferred.

  The silicone rubber layer can be appropriately selected from known ones as described in JP-A-7-164773 and the like. However, the silicone rubber layer composition described in JP-A-10-244773 is obtained by a condensation reaction. Two types, a condensation crosslinking type to be cured and an addition crosslinking type to cure the silicone rubber layer composition by an addition reaction, are preferably used.

  Examples of the condensation-crosslinking type silicone rubber layer include a linear organopolysiloxane having hydroxyl groups at both ends and a reactive silane compound that crosslinks with the organopolysiloxane to form a silicone rubber layer as essential components.

  The condensation-crosslinking type silicone rubber layer is used to increase the reaction efficiency of the condensation-crosslinking reaction between the organopolysiloxane having a hydroxyl group at both ends and a reactive silane compound, so that the organic carboxylic acid, titanate, stannate, aluminum organic A condensation catalyst such as an ether or a platinum-based catalyst can be appropriately reacted to perform a condensation reaction and be cured. The compounding ratio in the silicone rubber layer of the organopolysiloxane having a hydroxyl group at both ends, a reactive silane compound and a condensation catalyst is 80 to 80% of the organopolysiloxane having a hydroxyl group at both ends with respect to the solid content of the entire silicone rubber layer. 98% by mass, preferably 85-98% by mass, the reactive silane compound is usually 2-20% by mass, preferably 2-15% by mass, more preferably 2-7% by mass, and the condensation catalyst is 0.05-5%. It is 0.1 mass%, Preferably it is 0.1-3 mass%, More preferably, it is 0.1-1 mass%.

  The condensation-crosslinking type silicone rubber layer contains 2-15% by mass, preferably 3-12% by mass, of the polysiloxane other than the polyorganosiloxane having hydroxyl groups at both ends with respect to the total solid content of the silicone rubber layer. It can be made. Examples of the polysiloxane include polydimethylsiloxane having Mw of 10,000 to 1,000,000 having both ends trimethylsilylated.

  On the other hand, the addition-crosslinking type silicone rubber layer is composed of an organopolysiloxane having at least two aliphatic unsaturated groups in one molecule and a silicone rubber layer that is crosslinked with the organopolysiloxane to form Si-- Examples thereof include an organopolysiloxane having at least two H bonds as an essential component.

  The structure of the organopolysiloxane having at least two aliphatic unsaturated groups in one molecule may be any of a chain, a ring, and a branch, but a chain is preferable. Examples of fatty acid unsaturated groups include vinyl, allyl, butenyl, pentenyl, hexenyl and other alkenyl groups; cyclopentenyl, cyclohexenyl, cycloheptenyl, cyclooctenyl and other cycloalkenyl groups; ethynyl, Examples thereof include alkynyl groups such as propynyl group, butynyl group, pentynyl group, and hexynyl group. Among these, an alkenyl group having an unsaturated bond at the terminal is preferable from the viewpoint of reactivity, and a vinyl group is particularly preferable. Further, the remaining substituent other than the aliphatic unsaturated group is preferably a methyl group.

  The Mw of the organopolysiloxane having at least two aliphatic unsaturated groups in one molecule is usually 500 to 500,000, preferably 1000 to 3000000.

  The structure of the organopolysiloxane having at least two Si—H bonds in one molecule may be any of a chain, a ring, and a branch, but a chain is preferable. The Si—H bond may be either at the end or in the middle of the siloxane skeleton, and the proportion of hydrogen atoms to the total number of substituents is usually 1 to 60%, preferably 2 to 50%. The remaining substituents other than hydrogen atoms are preferably methyl groups. Mw of the organopolysiloxane having at least two Si-H bonds in one molecule is usually 300 to 300,000, preferably 500 to 200,000. If Mw is extremely high, sensitivity and image reproducibility are liable to be lowered.

  An addition reaction catalyst is usually used for addition reaction of an organopolysiloxane having at least two aliphatic unsaturated groups in one molecule and an organopolysiloxane having at least two Si-H bonds in one molecule. The addition reaction catalyst can be arbitrarily selected from known catalysts, but a platinum-based catalyst is preferable, and one or a mixture of two or more selected from a platinum group metal and a platinum-based compound is used.

  Examples of the platinum group metal include platinum alone (eg, platinum black), palladium alone (eg, palladium black), and rhodium alone. Examples of platinum group compounds include chloroplatinic acid, platinum-olefin complexes, platinum-alcohol complexes, platinum-ketone complexes, platinum and vinylsiloxane complexes, tetrakis (triphenylphosphine) platinum, tetrakis (triphenylphosphine) palladium, and the like. Is exemplified. Among these, those obtained by dissolving chloroplatinic acid or a platinum-olefin complex in an alcohol solvent, a ketone solvent, an ether solvent, a hydrocarbon solvent, or the like are particularly preferable.

  The blending ratio of each composition forming the silicone rubber layer is 80 to 98% by mass of organopolysiloxane having at least two fatty acid unsaturated groups in one molecule with respect to the total solid content of the silicone rubber layer. , Preferably 85 to 98% by mass, 2 to 20% by mass, preferably 2 to 15% by mass of the organopolysiloxane having at least two Si—H bonds in one molecule, and the addition reaction catalyst is It is 0.00001-10 mass%, Preferably it is 0.0001-5 mass%.

  In addition to the above composition, the addition-crosslinking type silicone rubber layer has a water content represented by the general formula (VII) described in JP-A-10-244773 for the purpose of increasing the film strength of the silicone rubber layer. An amino-based organosilicon compound having a decomposable group can be added.

  The amino-based organosilicon compound is 0 to 10% by mass, preferably 0 to 5% by mass, based on the total solid content of the silicone rubber layer.

  A curing retarder can be added to the addition-crosslinking type silicone rubber layer. The curing retarder can be arbitrarily selected from generally known acetylenic alcohols, maleic esters, silylated products of acetylenic alcohols, silylated products of maleic acid, triallyl isocyanurate, vinyl siloxane and the like.

  Although the addition amount of this hardening retarder changes with desired hardening speed | rates, it is 0.0001-1.0 mass part normally with respect to the total solid of a silicone rubber layer.

  The silicone rubber layer composition is dissolved in an appropriate solvent and used as a solution.

  Coating solvents include n-hexane, cyclohexane, petroleum ether, aliphatic hydrocarbon solvent Exxon Chemical Co., Ltd .: Isopar E, H, G and these solvents and ketones such as methyl ethyl ketone and cyclohexanone, butyl acetate, acetic acid Esters such as amyl and ethyl propionate, hydrocarbons and halogenated hydrocarbons such as toluene, xylene, monochlorobenzene, carbon tetrachloride, trichloroethylene and trichloroethane, ethers such as methyl cellosolve, ethylthrosolve and tetrahydrofuran, and A mixed solvent with propylene glycol monomethyl ether acetate, bentoxone, dimethylformamide and the like can be used.

  The thickness of the silicone rubber layer used in the present invention is preferably 0.05 to 100 μm, more preferably 0.5 to 20 μm, and in the case of an organic thin film transistor element, preferably 0.05 to 10 μm, more preferably 0. .1 to 2 μm.

  In the present invention, the patterning method of the silicone rubber layer includes a method of combining with the photosensitive layer. For example, after the silicone rubber layer is provided on the photosensitive layer, the photosensitive layer is exposed and developed to obtain a photosensitive layer, Remove the silicone rubber layer. Any photosensitive layer may be used as long as the silicone rubber layer can be patterned. As the photosensitive layer, for example, a photosensitive layer used in a patterning method used in a waterless flat plate technique can be used. Preferably, it is an ablation layer.

  The ablation layer refers to an insulating layer that is ablated by irradiation with high-density energy light and changes the adhesion between the electrode material repellent layer and the lower layer of the ablation layer. Ablation as used herein means that the ablation layer completely scatters due to physical or chemical changes, a part of the ablation layer breaks or scatters, and is physically or chemically only near the interface of the support or the conductive polymer layer. This includes a phenomenon in which the adhesiveness between the electrode material repulsive layer and the lower layer changes as a result of ablation.

  The ablation layer used in the present invention can be composed of an energy light absorber, a binder resin, and various additives added as necessary.

  As the energy light absorber, various organic and inorganic materials that absorb the energy light to be irradiated can be used. For example, when the laser light source is an infrared laser, pigments, dyes, metals, metal oxides, metals that absorb infrared rays Ferrite metal powder such as metal magnetic powder mainly composed of nitride, metal carbide, metal boride, graphite, carbon black, titanium black, Al, Fe, Ni, Co, etc. can be used. Black, cyanine-based pigments, and Fe-based ferromagnetic metal powders are preferred. Content of an energy light absorber is about 30-95 mass% of an ablation layer formation component, Preferably it is 40-80 mass%.

  The binder resin for the ablation layer can be used without particular limitation as long as it can sufficiently retain the colorant fine particles.

  Examples of such binder resins include polyurethane resins, polyester resins, vinyl chloride resins, polyvinyl acetal resins, cellulose resins, acrylic resins, phenoxy resins, polycarbonates, polyamide resins, phenol resins, and epoxy resins. Can be mentioned. The content of the binder resin is about 5 to 70% by mass, preferably 20 to 60% by mass, of the ablation layer forming component.

  The ablation layer may contain a cross-linking agent or a polymer material and be cured in order to improve the adhesion with the adjacent electrode material repulsive layer or the lower layer. Moreover, the material used for the photosensitive layer of the so-called heat mode waterless lithographic printing plate can be used.

The high-density energy light can be used without particular limitation as long as it is active light that generates ablation. As an exposure method, flash exposure using a xenon lamp, a halogen lamp, a mercury lamp, or the like may be performed through a photomask, or scanning exposure may be performed by converging laser light or the like. An infrared laser, particularly a semiconductor laser, whose output per laser beam is 20 to 200 mW is most preferably used. The energy density is preferably 50 to 500 mJ / cm ^2, more preferably a 100~300mJ / cm ^2.

  As the other photosensitive layer, a photosensitive resin layer can be preferably used, and known materials of positive type and negative type can be used. Examples of such photosensitive resin materials include (1) dye-sensitized photopolymerization photosensitivity as disclosed in JP-A-11-271969, JP-A-2001-117219, JP-A-11-311859, and JP-A-11-352691. Materials (2) Infrared lasers such as JP-A-9-179292, US Pat. No. 5,340,699, JP-A-10-90885, JP-A-2000-321780, and JP-A-2001-154374 are made photosensitive. (3) JP-A-9-171254, JP-A-5-115144, JP-A-10-87733, JP-A-9-43847, JP-A-10-268512, JP-A-11-194504, JP-A-11-223936 11-84657, 11-174681, 7-285275, JP 2000-56452, WO 97/39894 Positive photosensitive material having photosensitivity to infrared laser, such as Nos. 98/42507 and the like. Preference is given to (2) and (3) in that the process is not limited to a dark place.

  Solvents for forming the coating solution of photosensitive resin include propylene glycol monomethyl ether, propylene glycol monoethyl ether, methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve, ethyl cellosolve acetate, dimethylformamide, dimethyl sulfoxide, dioxane, acetone, cyclohexanone , Trichlorethylene, methyl ethyl ketone and the like. These solvents are used alone or in admixture of two or more.

  As a method for forming the photosensitive layer, methods such as spray coating, spin coating, blade coating, dip coating, casting, roll coating, bar coating, and die coating are used.

  As a light source for performing patterning exposure on the photosensitive layer, a laser is preferable, for example, an Ar laser, a semiconductor laser, a He-Ne laser, a YAG laser, a carbon dioxide gas laser, and the like, preferably those having an oscillation wavelength in the infrared, It is a semiconductor laser. The output is suitably 50 mW or more, preferably 100 mW or more. Thereby, patterning can be performed with high accuracy.

  In the present invention, the silicone rubber layer can be patterned by exposing and developing the photosensitive layer. Specifically, the photosensitive layer and the silicone rubber layer are exposed by exposing the photosensitive layer. The adhesiveness changes, and in this state, patterning is formed on the silicone rubber layer by developing the silicone rubber layer by brushing or the like.

  In the present invention, an organic semiconductor solution is supplied to the patterned silicone rubber layer to form an organic semiconductor material thin film (layer) pattern.

  In addition, the repellent layer according to the present invention can be directly applied to the silicone rubber layer composition by, for example, an electrostatic suction ink jet (SIJ) apparatus as described in Japanese Patent Application No. 2004-274754. Patterning paper may be formed at a predetermined position on the substrate.

  Hereinafter, in the thin film transistor of the present invention, the recording head 20 and the member related to the recording head 20 of the SIJ apparatus capable of discharging droplets of extremely fine diameters used for forming the silicone rubber layer will be described with reference to FIGS. explain.

  FIG. 3 is a cross-sectional view of a recording head having nozzles and members related to the recording head, and FIG. 4 is an explanatory diagram showing the relationship between the ink ejection operation and the voltage applied to the ink.

  FIG. 4A shows a state where no discharge is performed, and FIG. 4B shows a discharge state.

  In FIG. 3, the recording head 20 is provided with an ultrafine nozzle 21 that discharges ink droplets of chargeable ink from its tip.

  A counter electrode 23 is provided below the nozzle 21 of the recording head 20 so as to oppose the nozzle 21, and the counter electrode 23 has a counter surface that opposes the tip of the nozzle 21, and ink droplets are formed on the counter surface. The substrate K that receives the landing is supported.

  In addition, the recording head 20 includes an ink supply unit that supplies ink to the flow path (nozzle flow path) 22 in the nozzle 21, and an ejection voltage application unit 25 that applies a discharge voltage to the ink in the nozzle 21. It is connected.

  A part of the nozzle 21 and the ink supply unit and a part of the discharge voltage applying unit 25 are formed integrally with the nozzle plate 26.

  The recording head 20 is a scanning recording head that can be scanned in a direction (front and back direction in the figure) orthogonal to the transport direction (left and right direction in the figure) of the substrate K by a driving mechanism (not shown). (Solution) A repellent discharge liquid is supplied from an ink tank (not shown) of the ink supply means, which will be described later, and the recording head 20 discharges from the nozzles 21 as ink droplets.

(nozzle)
The nozzle 21 is integrally formed with a lower surface layer 26c of the nozzle plate 26 described later, and is erected vertically from the flat plate surface of the nozzle plate 26. Further, the nozzle 21 is formed with a flow path 22 penetrating from the tip portion along the center line.

The nozzle 21 is formed with an ultrafine diameter. Specifically, the inner diameter d of the tip portion A of the nozzle 21 is 30 μm or less, but may be less than 20 μm, 8 μm or less, or 4 μm or less. As an example of specific dimensions of each part, the nozzle inner diameter d is 1 μm, the external diameter d ₁ at the tip of the nozzle 21 is 2 μm, the root diameter d ₂ of the nozzle 21 is 5 μm, and the height h of the nozzle 21 is 100 μm. The shape is formed in a truncated cone shape that is close to a conical shape. The entire nozzle 21 is formed of an insulating resin material together with the lower surface layer 26 c of the nozzle plate 26.

  In addition, each dimension of a nozzle is not limited to the said example. In particular, the nozzle inner diameter d is within a range in which an ejection voltage that enables ejection of ink droplets is less than 1000 V due to the effect of electric field concentration, which will be described later. The diameter (for example, 0.2 μm), which is a range where it is feasible to form a through hole through which ink passes by the current nozzle forming technique, is set as the lower limit. However, it may be 0.2 μm or less if possible.

(Ink supply means)
The ink supply means is provided at a position inside the nozzle plate 26 and at the base of the nozzle 21 and also supplies ink to the ink chamber 24 from an external ink tank (not shown). An ink supply path 27 is provided, and a supply pump (not shown) that is connected to the ink supply path 27 and applies an ink supply pressure to the ink chamber 24 is provided.

  Ink is stored in the external ink tank, and the supply pump supplies ink to the tip of the nozzle 21 and maintains the supply pressure in a range that does not spill from the tip (FIG. 4). (See (A)).

(Discharge voltage application means)
A bias power source 30 for constantly applying a DC bias voltage to a discharge electrode 28 for applying a discharge voltage provided inside the nozzle plate 26 and at a boundary position between the ink chamber 24 and the flow path 22 in the nozzle; An ejection voltage applying means 25 having an ejection voltage power supply 29 for applying a pulse voltage, which is a potential required for ejection, superimposed on a bias voltage is connected to 28.

  The discharge electrode 28 is in direct contact with the ink inside the ink chamber 24 to charge the ink and apply a discharge voltage.

  The bias voltage from the bias power source 30 is applied in a voltage range in which ink is not ejected, so that the width of the voltage to be applied during ejection is reduced in advance, thereby improving the responsiveness during ejection. ing.

  The ejection voltage power supply 29 applies the pulse voltage superimposed on the bias voltage only when ejecting ink. At this time, the value of the pulse voltage is set so that the superimposed voltage V satisfies the following equation.

However, γ: ink surface tension, ε ₀ : vacuum dielectric constant, r: nozzle radius, k: proportional constant (1.5 <k <8.5) depending on the nozzle shape.

  As an example, the bias voltage is applied at DC 300 [V] and the pulse voltage is marked at 100 [V]. In this case, the superimposed voltage at the time of discharge is 400 [V].

(Nozzle plate)
The nozzle plate 26 includes a base layer 26a positioned in the uppermost layer in FIG. 3, a flow path layer 26b forming an ink supply path positioned therebelow, and a lower surface layer formed further below the flow path layer 26b. 26c, and the discharge electrode 28 described above is interposed between the flow path layer 26b and the upper surface layer 26c.

  The base layer 26a is formed of a silicon substrate or a highly insulating resin or ceramic, forms a soluble resin layer on the base layer 26a, and removes only a portion that follows the pattern of the supply path 27 and the ink chamber 24, An insulating resin layer is formed on the removed portion.

  This insulating resin layer becomes the flow path layer 26b. Then, the discharge electrode 28 is formed on the lower surface of the insulating resin layer by plating with a conductive material (for example, NiP), and an insulating resist resin layer is further formed thereunder. Since the resist resin layer becomes the lower surface layer 26 c, the resin layer is formed with a thickness in consideration of the height of the nozzle 21.

  Then, this insulating resist resin layer is exposed by an electron beam method or a femtosecond laser to form a nozzle shape. The nozzle internal flow path 22 is also formed by laser processing. Then, the dissolvable resin layer according to the pattern of the supply path 27 and the ink chamber 24 is removed, and the supply path 27 and the ink chamber 24 are opened to complete the nozzle plate.

(Counter electrode)
The counter electrode 23 has a counter surface perpendicular to the nozzle 21 as described above, and supports the thin film transistor K along the counter surface. As an example, the distance L from the tip of the nozzle 21 to the opposing surface of the opposing electrode 23 is set to 100 [μm].

  Since the counter electrode 23 is grounded, the ground potential is always maintained. Therefore, when a pulse voltage is applied, an ink droplet ejected by an electrostatic force generated by an electric field generated between the tip A of the nozzle 21 and the opposing surface is guided to the opposing electrode 23 side.

  Since the recording head 20 can eject ink droplets in a state where the electric field strength is increased by concentration of the electric field at the tip A of the nozzle 21, the ink droplets can be ejected without being guided by the counter electrode 23. Although possible, it is desirable that induction by electrostatic force is performed between the nozzle 21 and the counter electrode 23. In addition, the charge of the charged ink droplet can be released by grounding the counter electrode 23.

(ink)
The ink preferably does not contain particles having a diameter of 0.3 μm or more.

  More specifically, the ink has a viscosity of 0.1 to 1000 mPa · s (preferably 1 to 100 mPa · s) and a surface tension of 20 to 70 mN / m (preferably 25 to 50 mN / m). Some inks are applicable. When the viscosity of the ink is less than 0.1 mPa · s or greater than 1000 mPa · s, the ink ejection from the nozzle 21 becomes unstable. Further, when the surface tension of the ink is less than 20 mN / m, the ink droplets ejected from the nozzle 21 are likely to bleed into the substrate K. When the surface tension of the ink is greater than 70 mN / m, each pixel of the substrate K cannot be completely filled with the ink droplets ejected from the nozzle 21.

(Discharge operation of minute ink droplets by recording head)
The operation of the recording head 20 will be described with reference to FIGS.

  In FIG. 4, the horizontal axis represents time T, and the vertical axis represents the superimposed voltage V generated by the ejection voltage power supply 29 and the bias power supply 30.

  Ink is supplied to the nozzle flow path 22 by the supply pump of the ink supply means, and a bias voltage is applied to the ink via the discharge electrode 28 by the bias power supply 30.

  In such a state, the ink is charged and a meniscus that is recessed in the tip end portion A of the nozzle 21 is formed (FIG. 4A).

  When a pulse voltage is applied by the discharge voltage power supply 29, the electric field is concentrated at the tip of the nozzle 21, and the ink is guided to the tip of the nozzle 21 by the electrostatic force due to the concentrated electric field, and protrudes to the outside. In addition, an electric field is concentrated on the apex of the convex meniscus, and finally, a minute ink droplet is ejected toward the counter electrode 23 against the surface tension of the ink (FIG. 4B).

  In this case, an ink droplet having a droplet amount of 1 to 400 fl per droplet is ejected from the nozzle 21.

  Since the SIJ apparatus having the recording head 20 described above has a small diameter, it is possible to easily perform control for reducing the discharge flow rate per unit time due to the low nozzle conductance and to narrow the pulse width. Ink ejection with a sufficiently small ink droplet (an ink droplet having a droplet amount of 1 to 400 fl per droplet) is realized.

  Furthermore, since the ejected ink droplets are charged, the vapor pressure is reduced even for very small ink droplets and the evaporation is suppressed, so the loss of ink droplet mass is reduced and the flight is stabilized. In addition, the ink droplet landing accuracy is prevented from being lowered.

In addition, as described above, the amount of ink droplets ejected from the nozzle 21 can be set to 1 to 400 fl as described above, and the ink ejected from the nozzle 21 and landed on the thin film transistor K Since the droplet adhesion amount can be suppressed to 0.2 to 5.6 ml / m ² , each dot diameter of the ink droplet adhered to the thin film transistor K can be greatly reduced. Accordingly, the insulating region width (channel length) required to be 10 μm or less, which has been a problem in the past, can be reduced, such as ink bleeding, poor drying of the ink itself, and variations in the insulating region width (channel length). Detrimental effects can be suppressed, and as a result, a high-definition insulating region with a plurality of ultrafine dots can be formed on the organic semiconductor layer.

  In the above embodiment, in order to obtain the electrowetting effect on the nozzle 21, an electrode is provided on the outer periphery of the nozzle 21, or an electrode is provided on the inner surface of the nozzle internal flow path 22, and the insulating film is coated thereon. May be.

  By applying a voltage to this electrode, the wettability of the inner surface of the nozzle flow path 22 can be increased by the electrowetting effect for the ink to which the voltage is applied by the ejection electrode 28, and the inside of the nozzle can be increased. Ink supply to the flow path 22 can be performed smoothly, and it is possible to discharge well and improve the responsiveness of discharge.

  In the above embodiment, the ejection voltage application means 25 constantly applies a bias voltage and ejects ink droplets using a pulse voltage as a trigger. However, an alternating current or continuous rectangular wave is always applied with an amplitude required for ejection. Moreover, it is good also as a structure which discharges by switching the high and low of the frequency.

  Ink discharge is essential to eject ink droplets, and even if a discharge voltage is applied at a frequency that exceeds the speed at which the ink is charged, no discharge is performed. Is done. Therefore, when discharging is not performed, the discharge voltage is applied at a frequency higher than the dischargeable frequency, and control is performed to reduce the frequency to a frequency band that can be discharged only when discharging is performed, thereby controlling ink discharge. Is possible. In such a case, since the voltage applied to the ink itself does not change, it is possible to further improve the responsiveness and thereby improve the ink droplet landing accuracy.

  The layer containing the siloxane compound thus formed, that is, the pattern region A containing the siloxane compound has a low surface energy and repels the organic semiconductor solution, so that the applied solution is repelled in the drying process and the pattern region. A cast film of an organic semiconductor material is formed in an adjacent region outside the pattern region A, gathering in a region not containing the siloxane compound in contact with A.

  The contact angle of water in the pattern region A is preferably 70 degrees or more. In addition, it is preferable that the contact angle of toluene in the pattern region A is larger than the contact angle of toluene in other adjacent regions because highly accurate patterning is possible. Although there are influences such as the surface roughness of the substrate, the contact angle of toluene in the pattern region A is 3 to 20 degrees, more preferably 5 to 15 degrees. Moreover, the contact angle of toluene in other adjacent regions is preferably 15 to 100 degrees, and more preferably 20 to 90 degrees.

  In this way, by forming a region containing a polysiloxane compound, specifically a silicone rubber layer, on the substrate, the organic semiconductor material solution is formed in the pattern region A by repelling droplets of the organic semiconductor material solution. The organic semiconductor thin film is formed with high accuracy by collecting the droplets in other areas close to this.

  For example, in the case of a bottom-gate thin film transistor, a gate electrode is provided over a support, and a gate insulating layer is provided over the gate electrode. Further, a pattern region A containing a siloxane compound is provided on the gate insulating layer so that an organic semiconductor material thin film is formed in the adjacent region. A semiconductor thin film can be formed. A bottom gate type thin film transistor is configured by providing a source electrode and a drain electrode on both sides of the organic semiconductor layer pattern.

  Here, the pattern region A containing a siloxane compound can also be used as an electrode material repellent layer when the electrode is formed from a fluid electrode material.

  The organic semiconductor thin film of the present invention is thus patterned using the surfaces having different characteristics formed on the substrate. Next, the organic thin film transistor and the organic thin film manufactured using the organic semiconductor thin film of the present invention are used. Other components of the thin film transistor will be described.

[Organic semiconductor thin film: Organic semiconductor thin layer]
In the present invention, as the organic semiconductor material constituting the organic semiconductor thin film (also referred to as “organic semiconductor thin layer”), various condensed polycyclic aromatic compounds and conjugated compounds described later can be applied.

  Examples of the condensed polycyclic aromatic compound as the organic semiconductor material include, for example, anthracene, tetracene, pentacene, hexacene, heptacene, chrysene, picene, fluorene, pyrene, peropyrene, perylene, terylene, quaterylene, coronene, ovalene, circumcamanthracene, Examples thereof include bisanthene, zestrene, heptazethrene, pyranthrene, violanthene, isoviolanthene, cacobiphenyl, phthalocyanine, porphyrin, and derivatives thereof.

  Examples of the conjugated compound include polythiophene and its oligomer, polypyrrole and its oligomer, polyaniline, polyphenylene and its oligomer, polyphenylene vinylene and its oligomer, polythienylene vinylene and its oligomer, polyacetylene, polydiacetylene, tetrathiafulvalene compound, quinone And compounds, cyano compounds such as tetracyanoquinodimethane, fullerenes and derivatives or mixtures thereof.

  In particular, among polythiophene and oligomers thereof, thiophene hexamer, α-seccithiophene α, ω-dihexyl-α-sexualthiophene, α, ω-dihexyl-α-kinkethiophene, α, ω-bis (3- Oligomers such as butoxypropyl) -α-sexithiophene can be suitably used.

  Further, metal phthalocyanines such as copper phthalocyanine and fluorine-substituted copper phthalocyanine described in JP-A No. 11-251601, naphthalene 1,4,5,8-tetracarboxylic acid diimide, N, N′-bis (4-trifluoromethylbenzyl) ) Naphthalene 1,4,5,8-tetracarboxylic acid diimide, N, N'-bis (1H, 1H-perfluorooctyl), N, N'-bis (1H, 1H-perfluorobutyl) and N, N ' -Dioctylnaphthalene 1,4,5,8-tetracarboxylic acid diimide derivatives, naphthalene 2,3,6,7 tetracarboxylic acid diimides and other naphthalene tetracarboxylic acid diimides, and anthracene 2,3,6,7-tetracarboxylic acid Condensed ring tetracarboxylic acid such as anthracene tetracarboxylic acid diimides such as acid diimide Bonn acid diimides, C60, C70, C76, C78, C84, such as fullerenes, carbon nanotubes, such as SWNT, merocyanine dyes, such as dyes such as hemicyanine dyes, and the like.

  Among these π-conjugated materials, at least one selected from the group consisting of condensed polycyclic aromatic compounds such as pentacene, fullerenes, condensed ring tetracarboxylic acid diimides, and metal phthalocyanines is preferable.

  Other organic semiconductor materials include tetrathiafulvalene (TTF) -tetracyanoquinodimethane (TCNQ) complex, bisethylenetetrathiafulvalene (BEDTTTTF) -perchloric acid complex, BEDTTTTF-iodine complex, TCNQ-iodine complex. Organic molecular complexes such as can also be used. Furthermore, (sigma) conjugated polymers, such as polysilane and polygermane, and organic-inorganic hybrid material as described in Unexamined-Japanese-Patent No. 2000-260999 can also be used.

  Of the polythiophene and oligomers thereof, a thiophene oligomer represented by the following general formula (2) is preferable.

  In the formula, R represents a substituent.

<< Thiophene oligomer represented by formula (2) >>
The thiophene oligomer represented by the general formula (2) will be described.

  In the general formula (2), examples of the substituent represented by R include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, hexyl group, octyl group, Dodecyl group, tridecyl group, tetradecyl group, pentadecyl group etc.), cycloalkyl group (eg cyclopentyl group, cyclohexyl group etc.), alkenyl group (eg vinyl group, allyl group etc.), alkynyl group (eg ethynyl group, propargyl etc.) Group), aryl group (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, Biphenylyl group, etc.), aromatic heterocyclic groups (for example, furyl) , Thienyl group, pyridyl group, pyridazyl group, pyrimidyl group, pyrazyl group, triazyl group, imidazolyl group, pyrazolyl group, thiazolyl group, benzoimidazolyl group, benzoxazolyl group, quinazolyl group, phthalazyl group, etc.), heterocyclic group (for example, , Pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxyl group (for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxyl Group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.), alkylthio group (eg, methylthio group, ethylthio group, propylthio group, pentylthio group, hexyl) O group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, etc.) , Ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group) Methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminosulfonyl group, dode Silylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group) 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecyl) Carbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonylamino group, Pyrcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, amino Carbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, Naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group, ethylurei group) Group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group) , Cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexyl) Sulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group (for example, phenylsulfonyl group, naphthylsulfonyl group) Group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino) Group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl) Group), cyano group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.).

  These substituents may be further substituted with the above substituents, or a plurality thereof may be bonded to each other to form a ring.

  Among them, a preferable substituent is an alkyl group, more preferably an alkyl group having 2 to 20 carbon atoms, and particularly preferably an alkyl group having 6 to 12 carbon atoms.

<End group of thiophene oligomer>
The terminal group of the thiophene oligomer used for this invention is demonstrated.

  The terminal group of the thiophene oligomer used in the present invention preferably does not have a thienyl group, and preferred groups as the terminal group include aryl groups (for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group). Group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group) Tert-butyl group, pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), halogen atoms (for example, fluorine atom, chlorine atom, bromine atom etc.) and the like.

<Stereoscopic properties of repeating units of thiophene oligomers>
The thiophene oligomer used in the present invention preferably has no head-to-head structure in the structure, and more preferably, the structure has a head-to-tail structure or a tail- It preferably has a to-tail structure.

  Regarding the head-to-head structure, head-to-tail structure, and tail-to-tail structure according to the present invention, for example, “π-electron organic solid” (1998, published by the Japan Society for the Science of Chemistry, edited by Japan Chemical Industry) 27-32, Adv. Mater. 1998, 10, no. Reference can be made to pages 2, 93 to 116, etc. Here, specific structural features of each are shown below.

  In addition, R is synonymous with R in the said General formula (2) here.

  Hereinafter, although the specific example of these thiophene oligomers used for this invention is shown, this invention is not limited to these.

  A method for producing these thiophene oligomers is described in Japanese Patent Application No. 2004-172317 (filed on June 10, 2004) by the present inventors.

  In this invention, it is preferable that an organic-semiconductor material has an alkyl group from solubility and affinity with the thin film formed with the said pretreatment agent. From this viewpoint, in the organic semiconductor thin film according to the present invention, the organic semiconductor material forming the organic semiconductor thin film preferably has the partial structure represented by the general formula (1).

  From the above viewpoint, a compound represented by the following general formula (OSC1) is particularly preferable as the organic semiconductor material.

In the formula, R _{1 to} R ₆ represent a hydrogen atom or a substituent, Z ₁ or Z ₂ represents a substituted or unsubstituted aromatic hydrocarbon ring, or a substituted or unsubstituted aromatic heterocyclic ring, and n1 or n2 Represents an integer of 0 to 3.

In the general formula (OSC1), examples of the substituent represented by R _{1 to} R ₆ include an alkyl group (for example, methyl group, ethyl group, propyl group, isopropyl group, tert-butyl group, pentyl group, tert-pentyl group). Group, hexyl group, octyl group, tert-octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, for example) Allyl group, 1-propenyl group, 2-butenyl group, 1,3-butadienyl group, 2-pentenyl group, isopropenyl group, etc.), alkynyl group (for example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (Also called aromatic carbocyclic group, aryl group, etc., for example, phenyl group, p-chlorophenyl group, Til group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (also called heteroaryl group, For example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3- Triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group , Indolyl group, carbazolyl group , Carbolinyl group, diazacarbazolyl group (in which one of carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc. ), Heterocyclic groups (eg, pyrrolidyl, imidazolidyl, morpholyl, oxazolidyl, etc.), alkoxy groups (eg, methoxy, ethoxy, propyloxy, pentyloxy, hexyloxy, octyloxy, dodecyl) Oxy group etc.), cycloalkoxy group (eg cyclopentyloxy group, cyclohexyloxy group etc.), aryloxy group (eg phenoxy group, naphthyloxy group etc.), alkylthio group (eg methylthio group, ethylthio group, propylthio group, Pencil Group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio group (eg, cyclopentylthio group, cyclohexylthio group, etc.), arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxy Carbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group etc.), aryloxycarbonyl group (eg phenyloxycarbonyl group, naphthyloxycarbonyl group etc.), sulfamoyl group (eg amino Sulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octylaminos Phonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, Octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc.), acyloxy group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group) Group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group, dimethylcarbonyl group) Ruamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group ( For example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylamino Carbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group) Ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group, naphthylureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl) Group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group, etc.), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, Cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group, etc.), arylsulfonyl group (phenylsulfonyl group, naphthyls) Phonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethylamino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino) Group, 2-pyridylamino group, etc.), halogen atom (eg, fluorine atom, chlorine atom, bromine atom, etc.), fluorinated hydrocarbon group (eg, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl) Group), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), and the like.

  These substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

In the general formula (OSC1), the aromatic hydrocarbon group and aromatic heterocyclic group represented by Z ₁ or Z ₂ are aromatic carbon atoms described as substituents represented by R _{1 to} R ₆ , respectively. It is synonymous with a hydrogen group and an aromatic heterocyclic group, respectively.

  Furthermore, a compound represented by the following general formula (OSC2) is preferable.

In the formula, R ₇ or R ₈ represents a hydrogen atom or a substituent, Z ₁ or Z ₂ represents a substituted or unsubstituted aromatic hydrocarbon ring, or a substituted or unsubstituted aromatic heterocyclic ring, and n1 or n2 Represents an integer of 0 to 3.

In the general formula (OSC2), the substituent represented by R ₇ or R ₈ has the same meaning as the substituents represented by R _{1 to} R ₆ in the general formula (OSC1). In addition, the aromatic hydrocarbon group and aromatic heterocyclic group represented by Z ₁ or Z ₂ are aromatic hydrocarbon groups and aromatic groups described as substituents represented by R _{1 to} R ₆ , respectively. Each has the same meaning as a heterocyclic group.

In the general formula (OSC2), the substituents R ₇ — and R ₈ — are preferably represented by the general formula (SG1).

In the formula, R _{9 to} R ₁₁ represent substituents, and X represents silicon (Si), germanium (Ge), or tin (Sn).

In the said general formula (SG1), the substituent represented by R < ₉ > -R < ₁₁ > is synonymous with the substituent represented by R < ₁ > -R < ₃ > in the said General formula (1).

  Specific examples of the compound represented by the general formula (OSC2) are shown below, but are not limited thereto.

  In the present invention, for example, a material having a functional group such as acrylic acid, acetamide, dimethylamino group, cyano group, carboxyl group, nitro group, benzoquinone derivative, tetracyanoethylene and tetracyanoquino Materials that accept electrons, such as dimethane and their derivatives, materials having functional groups such as amino, triphenyl, alkyl, hydroxyl, alkoxy, and phenyl, phenylenediamine, etc. Including substituted amines, anthracene, benzoanthracene, substituted benzoanthracenes, pyrene, substituted pyrene, carbazole and derivatives thereof, tetrathiafulvalene and derivatives thereof, and the like materials that serve as donors of electrons, So-called doping treatment It may be.

  The doping means introducing an electron-donating molecule (acceptor) or an electron-donating molecule (donor) into the thin film as a dopant. Accordingly, the doped thin film is a thin film containing the condensed polycyclic aromatic compound and the dopant. A well-known thing can be employ | adopted as a dopant used for this invention.

  As described above, the organic semiconductor material solution was surface-treated with the organic semiconductor material solution as described above by a printing method, an inkjet method, or a coating method such as a spin coating method, a die coating method, or a dip coating method. It can be formed by applying to the substrate surface.

  Among these, from the viewpoint of productivity, an ink jet method capable of forming a thin film easily and precisely using an organic semiconductor solution is preferable.

  As the solvent used for forming the solution of the organic semiconductor material, any solvent can be used as long as it can dissolve the organic semiconductor material. For example, hydrocarbon-based, alcohol-based, ether-based, ester-based, It is appropriately selected according to the organic semiconductor material from which a crystalline organic semiconductor thin film is to be obtained, from a wide range of organic solvents having an appropriate vapor pressure or boiling point, such as ketones and glycol ethers. Solvents having an atmospheric pressure boiling point in a range of 250 ° C. or lower are preferable because they have an appropriate evaporation rate of the solvent at the crystallization interface or the coating liquid end face. More preferably, it is 80 degreeC-150 degreeC. For example, chain ether solvents such as diethyl ether and diisopropyl ether, cyclic ether solvents such as tetrahydrofuran and dioxane, ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone, aromatic hydrocarbon solvents such as xylene and toluene, o- Aromatic solvents such as dichlorobenzene, nitrobenzene, m-cresol, aliphatic hydrocarbon solvents such as hexane, cyclohexane, tridecane, α-terpineol, and alkyl halide solvents such as chloroform and 1,2-dichloroethane, N -Methylpyrrolidone, carbon disulfide and the like can be preferably used, but in particular, alicyclic hydrocarbon solvents such as cyclohexane and cyclopentane, and aromatic hydrocarbon solvents such as toluene and xylene. Etc. are preferred And the like as.

  The surface energy of the solvent is preferably 10 N / m to 40 N / m at 25 ° C. Furthermore, the solvent which is 15 N / m-30 N / m is preferable.

  In addition, as described in Advanced Material 1999 No. 6, p. 480 to 483, a precursor such as pentacene is soluble in a solvent, a target organic material formed by heat treatment of a precursor film formed by coating A thin film may be formed.

  The film thickness of these organic semiconductor layers is not particularly limited, but the characteristics of the obtained transistor are often greatly influenced by the film thickness of the organic semiconductor layer, and the film thickness varies depending on the organic semiconductor. Generally, 1 μm or less, particularly 10 to 300 nm is preferable.

  Furthermore, according to the organic semiconductor device of the present invention, at least one of the gate electrode and the source / drain electrode is formed by the method of manufacturing an organic semiconductor device of the present invention, whereby the low resistance electrode is formed into the organic semiconductor layer. It is possible to form the material layer without causing deterioration of the characteristics of the material layer.

  In the thin film transistor element of the present invention, the source electrode or the drain electrode is formed by the electroless plating method, but one of the source electrode and the drain electrode may be an electrode not using electroless plating together with the gate electrode. In that case, the electrode is formed by a known method or a known electrode material. The electrode material is not particularly limited as long as it is a conductive material. Platinum, gold, silver, nickel, chromium, copper, iron, tin, antimony lead, tantalum, indium, palladium, tellurium, rhenium, iridium, aluminum, ruthenium, Germanium, molybdenum, tungsten, tin oxide / antimony, indium tin oxide (ITO), fluorine doped zinc oxide, zinc, carbon, graphite, glassy carbon, silver paste and carbon paste, lithium, beryllium, sodium, magnesium, potassium, calcium , Scandium, titanium, manganese, zirconium, gallium, niobium, sodium, sodium-potassium alloy, magnesium, lithium, aluminum, magnesium / copper mixture, magnesium / silver mixture, magnesium / Aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide mixture, a lithium / aluminum mixture, or the like is used. Alternatively, a known conductive polymer whose conductivity is improved by doping or the like, for example, conductive polyaniline, conductive polypyrrole, or conductive polythiophene (such as a complex of polyethylenedioxythiophene and polystyrenesulfonic acid) is also preferably used.

  As a material for forming the source electrode or the drain electrode, among the materials listed above, those having low electrical resistance at the contact surface with the semiconductor layer are preferable. In the case of a p-type semiconductor, platinum, gold, silver, ITO, conductive Polymer and carbon are preferred.

  In the case of a source electrode or a drain electrode, those formed using a fluid electrode material such as a solution, paste, ink, or dispersion containing the above conductive material, in particular, a conductive polymer, or platinum, gold, A fluid electrode material containing fine metal particles containing silver and copper is preferred. The solvent or dispersion medium is preferably a solvent or dispersion medium containing 60% or more, preferably 90% or more of water, in order to suppress damage to the organic semiconductor.

  As the fluid electrode material containing metal fine particles, for example, a known conductive paste or the like may be used. Preferably, metal fine particles having a particle diameter of 1 to 50 nm, preferably 1 to 10 nm are used as necessary. It is a material dispersed in a dispersion medium that is water or any organic solvent using a dispersion stabilizer.

  Platinum, gold, silver, nickel, chromium, copper, iron, tin, antimony lead, tantalum, indium, palladium, tellurium, rhenium, iridium, aluminum, ruthenium, germanium, molybdenum, tungsten, zinc, etc. Can be used.

  As a method for producing such a dispersion of fine metal particles, metal ions are reduced in the liquid phase, such as a physical generation method such as gas evaporation method, sputtering method, metal vapor synthesis method, colloidal method, coprecipitation method, etc. Examples of the chemical production method for producing metal fine particles include colloidal methods described in JP-A-11-76800, JP-A-11-80647, JP-A-11-319538, JP-A-2000-239853, and the like. A dispersion of fine metal particles produced by a gas evaporation method described in JP-A Nos. 2001-254185, 2001-53028, 2001-35255, 2000-124157, 2000-123634, etc. is there. After forming an electrode using these metal fine particle dispersions and drying the solvent, the metal fine particles are obtained by heating in a shape within a range of 100 to 300 ° C., preferably 150 to 200 ° C. as necessary. An electrode pattern having a target shape is formed by heat fusion.

  As a method for forming an electrode, a method for forming an electrode using a known photolithographic method or a lift-off method, using a conductive thin film formed by a method such as vapor deposition or sputtering using the above as a raw material, or a metal foil such as aluminum or copper There is a method in which a resist is formed and etched by thermal transfer, ink jet or the like. Alternatively, a conductive polymer solution or dispersion, a dispersion containing metal fine particles, or the like may be directly patterned by an ink jet method, or may be formed from a coating film by lithography or laser ablation. Further, a method of patterning a conductive ink or conductive paste containing a conductive polymer or metal fine particles by a printing method such as relief printing, intaglio printing, planographic printing, or screen printing can also be used.

  The source electrode and the drain electrode are particularly preferably formed by using a photolithography method. In this case, a photo-sensitive resin solution is applied to the entire surface of the layer in contact with the organic semiconductor protective layer, and the photo-sensitive resin layer is formed. Form.

  As the photosensitive resin layer, the same positive and negative photosensitive resins used for patterning the protective layer can be used.

  In the photolithographic method, after that, patterning is performed using a metal fine particle-containing dispersion or a conductive polymer as a material for a source electrode and a drain electrode, and heat fusion is performed as necessary.

  The solvent for forming the photosensitive resin coating solution, the method for forming the photosensitive resin layer, and the like are as described in the patterning of the protective film.

  The same applies to the light source used for patterning exposure after the formation of the photosensitive resin layer and the developer used for developing the photosensitive resin layer. In addition, an ablation layer which is another photosensitive resin layer may be used for electrode formation. As for the ablation layer, the same ones as those used for the patterning of the protective layer may be mentioned.

  Various insulating films can be used as the gate insulating layer of the organic thin film transistor element of the present invention, and an inorganic oxide film having a high relative dielectric constant is particularly preferable. Inorganic oxides include silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, tin oxide, vanadium oxide, barium strontium titanate, barium zirconate titanate, lead zirconate titanate, lead lanthanum titanate, strontium titanate, Examples thereof include barium titanate, barium magnesium fluoride, bismuth titanate, strontium bismuth titanate, strontium bismuth tantalate, bismuth tantalate niobate, and yttrium trioxide. Of these, silicon oxide, aluminum oxide, tantalum oxide, and titanium oxide are preferable. Inorganic nitrides such as silicon nitride and aluminum nitride can also be suitably used.

  Examples of the method for forming the film include a vacuum process, a molecular beam epitaxial growth method, an ion cluster beam method, a low energy ion beam method, an ion plating method, a CVD method, a sputtering method, an atmospheric pressure plasma method, and a spray process. Wet processes such as coating methods, spin coating methods, blade coating methods, dip coating methods, casting methods, roll coating methods, bar coating methods, die coating methods, and other wet processes such as printing and ink jet patterning methods, etc. Can be used depending on the material.

  The wet process is a method of applying and drying a liquid in which fine particles of inorganic oxide are dispersed in an arbitrary organic solvent or water using a dispersion aid such as a surfactant as required, or an oxide precursor, for example, A so-called sol-gel method in which a solution of an alkoxide body is applied and dried is used.

  Among these, the atmospheric pressure plasma method is preferable.

  For the plasma CVD method or the atmospheric pressure plasma CVD method, for example, an apparatus disclosed in JP-A-10-1553, JP-A-2002-113805, JP-A-2003-303520, or JP-A-2004-238455 is used. Can be implemented.

  It is also preferable that the gate insulating layer is composed of an anodized film or the anodized film and an insulating film. The anodized film is preferably sealed. The anodized film is formed by anodizing a metal that can be anodized by a known method.

Examples of the metal that can be anodized include aluminum and tantalum, and the anodizing method is not particularly limited, and a known method can be used. An oxide film is formed by anodizing. Any electrolyte solution that can form a porous oxide film can be used as the anodizing treatment. Generally, sulfuric acid, phosphoric acid, oxalic acid, chromic acid, boric acid, sulfamic acid, benzenesulfone, and the like can be used. An acid or the like, a mixed acid obtained by combining two or more of these, or a salt thereof is used. The treatment conditions for anodization vary depending on the electrolyte used, and thus cannot be specified in general. In general, the electrolyte concentration is 1 to 80% by mass, the electrolyte temperature is 5 to 70 ° C., and the current density. The range of 0.5 to 60 A / dm ² , voltage of 1 to 100 volts, and electrolysis time of 10 seconds to 5 minutes is appropriate. A preferred anodizing treatment is a method in which an aqueous solution of sulfuric acid, phosphoric acid or boric acid is used as the electrolytic solution and the treatment is performed with a direct current, but an alternating current can also be used. The concentration of these acids is preferably 5 to 45% by mass, and the electrolytic treatment is preferably performed for ²⁰ to 250 seconds at an electrolyte temperature of 20 to 50 ° C. and a current density of 0.5 to 20 A / dm ² .

  In addition, as the organic compound film, polyimide, polyamide, polyester, polyacrylate, photo radical polymerization type, photo cation polymerization type photo curable resin, or a copolymer containing an acrylonitrile component, polyvinyl phenol, polyvinyl alcohol, novolac resin, Also, cyanoethyl pullulan or the like can be used.

  As the method for forming the organic compound film, the wet process is preferable.

  An inorganic oxide film and an organic oxide film can be laminated and used together. The thickness of these insulating films is generally 50 nm to 3 μm, preferably 100 nm to 1 μm.

  In the present invention, when an organic semiconductor layer is formed on the gate insulating layer, the surface treatment of the present invention is performed on the surface of the gate insulating layer, and then the solution containing the organic semiconductor material is applied, whereby the organic semiconductor The layer is formed in a pattern.

[About the board]
Various materials can be used as the support material constituting the substrate. For example, ceramic substrates such as glass, quartz, aluminum oxide, sapphire, silicon nitride, silicon carbide, silicon, germanium, gallium arsenide, gallium phosphide. In addition, a semiconductor substrate such as gallium nitrogen, paper, and non-woven fabric can be used. In the present invention, the support is preferably made of a resin, for example, a plastic film sheet can be used. Examples of plastic films include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), and cellulose. Examples include films made of triacetate (TAC), cellulose acetate propionate (CAP), and the like. By using a plastic film, the weight can be reduced as compared with the case of using a glass substrate, the portability can be improved, and the resistance to impact can be improved.

  It is also possible to provide an element protective layer on the organic thin film transistor element of the present invention. Examples of the protective layer include the inorganic oxides and inorganic nitrides described above, and the protective layer is preferably formed by the atmospheric pressure plasma method described above. Thereby, durability of an organic thin-film transistor element improves.

  In the thin film transistor element of the present invention, when the support is a plastic film, it preferably has at least one of an undercoat layer containing a compound selected from inorganic oxides and inorganic nitrides, and an undercoat layer containing a polymer.

  Inorganic oxides contained in the undercoat layer include silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, tin oxide, vanadium oxide, barium strontium titanate, barium zirconate titanate, lead zirconate titanate, titanate Examples thereof include lead lanthanum, strontium titanate, barium titanate, barium fluoride magnesium, bismuth titanate, strontium bismuth titanate, strontium bismuth tantalate, bismuth tantalate niobate, and yttrium trioxide. Examples of the inorganic nitride include silicon nitride and aluminum nitride.

  Of these, silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, and silicon nitride are preferable.

  In the present invention, the undercoat layer containing a compound selected from inorganic oxides and inorganic nitrides is preferably formed by the atmospheric pressure plasma method described above.

  Polymers used for the undercoat layer containing polymer include polyester resin, polycarbonate resin, cellulose resin, acrylic resin, polyurethane resin, polyethylene resin, polypropylene resin, polystyrene resin, phenoxy resin, norbornene resin, epoxy resin, vinyl chloride-vinyl acetate Copolymer, vinyl chloride resin, vinyl acetate resin, copolymer of vinyl acetate and vinyl alcohol, partially hydrolyzed vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinylidene chloride copolymer, vinyl chloride-acrylonitrile copolymer Polymer, ethylene-vinyl alcohol copolymer, polyvinyl alcohol, chlorinated polyvinyl chloride, ethylene-vinyl chloride copolymer, vinyl polymers such as ethylene-vinyl acetate copolymer, polyamide resin, ethylene-butadiene resin, Tajien - rubber-based resin such as acrylonitrile resin, silicone resin, and fluorine resins.

  Hereinafter, preferred embodiments of the method for producing a thin film transistor of the present invention will be described, but the present invention is not limited thereto.

<< Preferred Embodiment >>
Hereinafter, preferred embodiments of the present invention will be described. The present invention is not limited to this.

  In FIG. 1, the schematic sectional drawing of each process is shown about an example of preparation of the thin-film transistor using the organic-semiconductor thin film of this invention.

First, a polyethersulfone resin film (200 μm) was used as the substrate 1, and first, a corona discharge treatment was performed thereon under the condition of 50 W / m ² / min. Thereafter, an undercoat layer was formed in order to improve adhesion as follows.

(Formation of undercoat layer)
A coating solution having the following composition was applied to a dry film thickness of 2 μm, dried at 90 ° C. for 5 minutes, and then cured for 4 seconds from a distance of 10 cm under a 60 W / cm high-pressure mercury lamp.

Dipentaerythritol hexaacrylate monomer 60g
Dipentaerythritol hexaacrylate dimer 20g
Dipentaerythritol hexaacrylate trimer or higher component 20g
Diethoxybenzophenone UV initiator 2g
Silicone surfactant 1g
75g of methyl ethyl ketone
Methyl propylene glycol 75g
Further, a silicon oxide film having a thickness of 50 nm was formed on the layer by continuous atmospheric pressure plasma treatment under the following conditions, and these layers were used as undercoat layers (FIG. 3 (1)). As the atmospheric pressure plasma processing apparatus, an apparatus according to FIG. 6 described in JP-A No. 2003-303520 was used.

(Used gas)
Inert gas: helium 98.25% by volume
Reactive gas: oxygen gas 1.5 volume%
Reactive gas: Tetraethoxysilane vapor (bubbled with helium gas) 0.25% by volume
(Discharge conditions)
Discharge output: 10 W / cm ²
(Electrode condition)
As a power source, a high frequency power source manufactured by Pearl Industry was used and discharged at a frequency of 13.56 MHz.

  The electrode is coated with 1 mm of alumina by ceramic spraying on a stainless steel jacket roll base material having cooling means with cooling water, and then a solution obtained by diluting tetramethoxysilane with ethyl acetate is applied and dried, and then sealed by ultraviolet irradiation. This is a roll electrode having a dielectric (relative dielectric constant of 10) having a pore surface, smoothed surface and having a maximum surface roughness (Rmax) defined by JIS B 0601 of 5 μm (relative dielectric constant 10). On the other hand, as the application electrode, a hollow rectangular stainless steel pipe was coated with the same dielectric as described above under the same conditions. The undercoat layer is omitted in the figure.

<Formation of gate bus line and gate electrode>
Next, a gate bus line and a gate electrode 2 are formed.

That is, after the photosensitive resin composition liquid 1 having the following composition was applied on the undercoat layer 2 and dried at 100 ° C. for 1 minute, a photosensitive resin layer having a thickness of 2 μm was formed. The pattern of the gate bus line and the gate electrode was exposed with a semiconductor laser having an oscillation wavelength of 830 nm and an output of 100 mW at an energy density of 200 mJ / cm ² and developed with an alkaline aqueous solution to obtain a resist image. Furthermore, after forming an aluminum film having a thickness of 300 nm on the entire surface by sputtering, the remaining part of the photosensitive resin layer is removed by MEK, thereby producing the gate bus line and the gate electrode 2. .

(Photosensitive resin composition liquid 1)
Dye A 7 parts novolak resin (novolak resin co-condensed with phenol and m-, p-mixed cresol and formaldehyde (Mw = 4000, molar ratio of phenol / m-cresol / p-cresol is 5/57/38, respectively)) 90 parts Crystal violet 3 parts Propylene glycol monomethyl ether 1000 parts

  Next, an anodic oxide film was formed on the gate electrode as an auxiliary insulating film for smoothing and improving the insulating properties by the following anodic oxide film forming step (also omitted in the figure).

(Anodized film forming process)
After forming the gate electrode, the substrate is washed thoroughly, and the thickness of the anodic oxide film reaches 120 nm using a direct current supplied from a low-voltage power supply of 30 V in a 10 mass% ammonium phosphate aqueous solution for 2 minutes. Anodized. After thoroughly washing, steam sealing treatment was performed in a saturated steam chamber at 1 atm and 100 ° C. In this way, a gate electrode having an anodized film was produced on a polyether sulfone resin film subjected to a subbing treatment.

  Next, at a film temperature of 200 ° C., a silicon oxide layer having a thickness of 30 nm was provided using the above-described gas used in the atmospheric pressure plasma method, and the gate insulating layer 3 was formed by combining the anodic oxide film (alumina film). (1) of FIG.

(Used gas)
Inert gas: helium 98.25% by volume
Reactive gas: oxygen gas 1.5 volume%
Reactive gas: Tetraethoxysilane vapor (bubbled with helium gas) 0.25% by volume
(Discharge conditions)
Discharge output: 10 W / cm ²
As described above, the gate electrode and the gate insulating film were produced on a polyether sulfone resin film subjected to a subbing treatment.

  Next, a silicone rubber layer was formed on the gate insulating layer by the following method.

  A liquid obtained by diluting the following composition 1 on the gate insulating layer 3 with a single solvent of Isopar E ″ (isoparaffin-based hydrocarbon, manufactured by Exxon Chemical Co., Ltd.) to a solid content concentration of 10.3 mass% using an SIJ apparatus A droplet is discharged on both sides of the gate electrode adjacent to leave a layer formation region, dried, and made of a silicone rubber layer having a width of 3 μm in the region on both sides of the gate electrode as shown in FIG. Pattern region A (layer) 4 was formed, and the interval was set so that the channel length L of the organic semiconductor layer could be 30 μm.

(Composition of Composition 1)
α, ω-divinylpolydimethylsiloxane (molecular weight about 60,000) 100 parts HMS-501 (both end methyl (methylhydrogensiloxane)
(Dimethylsiloxane) copolymer, SiH group number / molecular weight = 0.69 mol / g, manufactured by Chisso Corp.) 7 parts vinyltris (methylethylketoxyimino) silane 3 parts SRX-212 (platinum catalyst, Toray Dow Corning Silicon ( 5 parts by this. On the surface of the gate insulating layer 3, the formation region of the organic semiconductor layer close to the pattern region A made of the silicone rubber layer was left as an opening. FIG. 1B is a cross-sectional view showing this state.

  Next, an organic semiconductor layer was formed over the surface-treated gate insulating layer using OSC2-1 (the following structure) as a semiconductor material. That is, a toluene solution (0.5% by mass) of OSC2-1 was prepared, and the toluene solution 4 ′ was ejected to an approximate region where a channel was to be formed by using a piezo ink jet method (FIG. 1 (3)). ). It dried for 3 minutes at 50 degreeC in nitrogen gas (FIG. 3 (4)-(5)). The organic semiconductor material solution droplets accurately gather between the pattern areas A on both sides formed by sandwiching the gate in accordance with drying, that is, evaporation of the solvent (FIG. 3 (4)), and contact the pattern areas A on the substrate. Then, an organic semiconductor layer 4 having a thickness of 20 nm was patterned and formed in a region where a channel was to be formed (FIG. 1 (5)).

<Source and drain electrode forming step> ((6) and (7) in FIG. 1)
After the formation of the organic semiconductor layer 4, an aqueous dispersion of PEDOT / PSS [polystyrene sulfonic acid and poly (ethylenedioxythiophene)] (Baytron P manufactured by Bayer) is applied to the surface on which the organic semiconductor layer is formed by a piezoelectric inkjet method. The electrode material liquid (5 ′, 6 ′) is discharged and supplied onto the organic semiconductor layer so that the channel length L is 30 μm including the silicone rubber layer portion (FIG. 1 (6)). The source electrode 5 and the drain electrode 6 were formed by drying this at 100 degreeC. Since the silicone rubber layer is present, the electrode material liquid does not get on the portion where the silicone rubber layer is present during the drying process, so that no electrode is formed. That is, a pattern like (7) in FIG. 1 is naturally formed.

  The electrode is a 20 nm thick layer made of polystyrene sulfonic acid and poly (ethylenedioxythiophene).

<< Preferred Embodiment 2 >>
In FIG. 2, the schematic sectional drawing of each process is shown about another example of preparation of the thin-film transistor using the organic-semiconductor thin film of this invention.

  A polyethersulfone resin film (200 μm) is used as a substrate, and a corona discharge treatment and an undercoat layer are provided thereon as in the first embodiment, and a gate bus line and a gate electrode 2, and further a gate insulating layer 3 are provided. Formed. ((1) in FIG. 1).

  Next, a silicone rubber layer was formed on the gate insulating layer 3 by the following method.

  A liquid obtained by diluting the following composition 1 with Isopar E ″ (isoparaffinic hydrocarbon, manufactured by Exxon Chemical Co., Ltd.) with a single solvent to a solid content concentration of 10.3% by mass leaves an organic semiconductor layer formation region using an SIJ apparatus. As shown in FIG. 2 (1), the liquid droplets are ejected onto the regions on both sides of the adjacent gate electrode and dried. As shown in FIG. 2 (1), the pattern region A made of a silicone rubber layer having a width of 3 μm is formed on both sides of the gate electrode. Layer).

(Composition of Composition 1)
α, ω-divinylpolydimethylsiloxane (molecular weight about 60,000) 100 parts HMS-501 (both end methyl (methylhydrogensiloxane)
(Dimethylsiloxane) copolymer, SiH group number / molecular weight = 0.69 mol / g, manufactured by Chisso Corp.) 7 parts vinyltris (methylethylketoxyimino) silane 3 parts SRX-212 (platinum catalyst, Toray Dow Corning Silicon ( (Made by Co., Ltd.) 5 parts Thereby, the formation region of the organic semiconductor thin film on the gate insulating layer 3 adjacent to the pattern region A made of the silicone rubber layer is left as an opening. FIG. 2A is a cross-sectional view showing this state.

  Next, an organic semiconductor layer was formed over the gate insulating layer using OSC2-1 as a semiconductor material. That is, a toluene solution (0.5% by mass) of OSC2-1 was prepared, and the solution 4 ′ was discharged to an approximate area where a channel partially including a silicone rubber layer was to be formed using a piezo ink jet method. (FIG. 2 (2)), and dried in nitrogen gas at 50 ° C. for 3 minutes (FIGS. 2 (2) to (5)). Liquid droplets gather accurately between the pattern areas A covered with the silicone rubber layers on both sides formed by sandwiching the gate electrode 2 in accordance with drying, that is, evaporation of the solvent (FIG. 2 (3)), and the pattern is formed on the substrate. In contact with the region A, an organic semiconductor layer 4 having a thickness of 20 nm was formed in a region where a channel is to be formed (FIG. 2 (4)).

<Electrode material repellent layer forming step> ((5) and (6) in FIG. 2)
Next, a solution in which the following composition 2 is dissolved in Isopar E ″ (isoparaffinic hydrocarbon, manufactured by Exxon Chemical Co., Ltd.) on the organic semiconductor layer 4 is used as an aqueous dispersion, and diluted to a solid content concentration of 10.3% by mass. The obtained material was ejected in accordance with a pattern by a piezo ink jet method, heated (100 ° C.), and dried to form a 0.4 μm thick silicone rubber layer electrode material repellent layer R by patterning (FIG. 2 ( 6)).

(Composition 2)
α, ω-divinylpolydimethylsiloxane (molecular weight about 60,000) 100 parts HMS-501 (both terminal methyl (methylhydrogensiloxane) (dimethylsiloxane) copolymer, SiH group number / molecular weight = 0.69 mol / g, Chisso 7 parts Vinyl tris (methyl ethyl ketoximino) silane 3 parts SRX-212 (platinum catalyst, manufactured by Toray Dow Corning Silicone Co., Ltd.) 5 parts <Source and drain electrode forming step> (( 7), (8))
After forming the electrode material repellent layer R, an aqueous dispersion of polystyrene sulfonic acid and poly (ethylenedioxythiophene) (Bayer's Baytron P) is applied to the surface on which the electrode material repellent layer is formed by a piezoelectric inkjet method. It is discharged and supplied onto the organic semiconductor layer so as to straddle the printed pattern portion silicone rubber layer (repulsion layer) including the layer R portion (FIG. 2 (7)). Since the electrode material repellent layer R is present, the ink is separated into the source and drain electrode portions after printing (FIG. 2 (8)), and the ink does not get on the portion having the electrode material repellent layer. Next, this is dried at 100 ° C. to form the source electrode 5 and the drain electrode 6. That is, the electrode pattern is naturally formed without patterning the source electrode and the drain electrode separately. The electrode is a 20 nm thick layer made of polystyrene sulfonic acid and poly (ethylenedioxythiophene). The organic thin-film transistor produced in (9) of FIG. 2 is shown.

The fabricated organic thin film transistor requires carrier mobility from the saturation region of the IV characteristics. As a result, the mobility is 0.4 cm ² / Vs or more, and the organic thin film transistor can operate well as a p-channel enhancement type FET. all right.

  In addition, since the positional accuracy of the organic semiconductor pattern was improved in the coating formation of the organic semiconductor thin film, there was no variation between the semiconductor elements in the manufacturing, and the reproducibility was good.

It is a schematic sectional drawing which shows an example of the manufacturing process of the thin-film transistor using the organic-semiconductor thin film of this invention. It is a schematic sectional drawing which shows another example of the manufacturing process of the thin-film transistor using the organic-semiconductor thin film of this invention. It is sectional drawing of the member which concerns on the recording head which has a nozzle, and a recording head. It is explanatory drawing which shows the relationship between the discharge operation of ink, and the voltage applied to ink.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Gate electrode 3 Gate insulating layer 4 Organic semiconductor layer 5 Source electrode 6 Drain electrode 20 Recording head 21 Nozzle 22 Flow dew 25 Discharge voltage application means

Claims (3)

An organic thin film transistor comprising an organic semiconductor thin film formed in a region in contact with the pattern region A after forming a pattern region A containing a siloxane compound. 2. The organic thin film transistor according to claim 1, wherein the organic semiconductor thin film is a cast film from a solution or dispersion of an organic semiconductor. 3. The organic thin film transistor according to claim 1, wherein a pattern region A is formed so as to surround a region where the organic semiconductor thin film is formed.

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