KR20060060776A - Method for manufacturing polythiophene derivatives soluble in organic solvents and application thereof - Google Patents

Abstract

The present invention provides a poly (3,4-alkoxythiophene) derivative represented by the following general formula (I) or a poly (3,4-ethylenedioxythiophene) represented by the general formula (II), which can be dissolved in an organic solvent. It relates to a process for the preparation of a derivative and its use.

Wherein R ₁ is a C ₅ to C ₁₈ long chain alkyl group, a cycloalkyl group, and an ethylene oxide substituent, and R ₂ is the same as R ₁ or a derivative of -OR and -NR and -OAr or -NAr. Aromatic substituents may be included.)

The organic solvent-soluble polythiophene derivatives of the present invention are organic thin film transistors such as organic transparent electrodes, capacitors of high-performance energy storage devices, electromagnetic shielding films, capacitors, batteries, and field effect transistors (FETs), organic as conductive polymer materials. It is useful as an organic polymer for an EL display, a solar cell, and a memory device using a multiphoton absorption phenomenon.

3,4-dioxythiophene derivative, poly (3,4-ethylenedioxythiophene) derivative, transparent electrode, surface resistance, transmittance, field effect transistor, organic thin film transistor, electrical conductivity, polymer solubility

Description

Method for preparing organic solvent soluble polythiophene derivative and use thereof {METHOD FOR MANUFACTURING POLYTHIOPHENE DERIVATIVES SOLUBLE IN ORGANIC SOLVENTS AND APPLICATION THEREOF}             

1 is a cross-sectional configuration diagram of a field effect transistor (FET) using the organic soluble polythiophene derivative of the present invention.

2 is a transparent electrode circuit diagram using the organic soluble polythiophene derivative of the present invention.

3 is a graph showing the solubility curve of the organic soluble polythiophene derivatives and PEDOT of the present invention.

4A and 4B are graphs showing resistance / voltage (I-V) characteristic curves for the organic soluble polythiophene derivatives of the present invention.

FIG. 5 is a graph showing ultraviolet-visible / near infrared spectra (UV-Vis./NIR Spectra) for the organic soluble polythiophene derivative compounds of the present invention. FIG.

Explanation of symbols on the main parts of the drawings

1 substrate 2 gate

3: gate insulating film 4: organic semiconductor thin film                 

5: source-drain electrode

The present invention relates to a process for the preparation of organic solvent soluble polythiophene derivatives and their use. The organic solvent-soluble polythiophene derivatives of the present invention are organic thin film transistors such as organic transparent electrodes, capacitors of high-performance energy storage devices, electromagnetic wave shielding films, capacitors, batteries, and field effect transistors (FETs), organic as conductive polymer materials. It is useful for the purpose of application as an organic polymer for an EL display, a solar cell, and a memory device using a multiphoton absorption phenomenon.

Organic polymer material is basically a molecular material composed of carbon and hydrogen, and has an advantage of easily obtaining various physical properties by converting the chemical structure of the constituent molecule through synthetic chemistry. In addition, polymer materials are inexpensive, lightweight, tough and excellent in processability compared to other materials, and thus occupy an important position as living materials for human beings such as fibers, plastics, films, coatings, adhesives, paints, and packaging materials. In addition, due to its excellent transparency, it is widely used as an optical material such as a lens, a plastic optical fiber (POF), a color filter, and a photoresist for semiconductor microfabrication.

Recently, an organic polymer material having a pi (π) -conjugated structure has been attracting more attention as an electrically conductive and photofunctional organic semiconductor material with the discovery of its semiconducting properties. In addition, it utilizes the excellent properties (light weight, elasticity, plasticity, large area, processability, and economic efficiency) of the polymer, and utilizes the micro-wiring that utilizes the anisotropy of conductivity and molecular orientation control of the polymer, and the interface between the conductive polymer and the metal and inorganic semiconductor. Large area solar cell used, rechargeable battery using change of chemical potential by doping, high reflectivity of polymer, optical information memory device using change by doping, conductivity change by temperature, temperature sensor using metal insulator transition, In addition, it is expected to use a wide range of separators, filters, antistatic, electronic shielding, photocatalyst and the like.

With the growing interest in converting metal or solid displays into more practical forms, the research and development of each material and device of organic transistors is actively conducted in both academic and industrial fields, and is the source of commercially available organic monomolecules and conductive polymer materials. There is a situation where we have to rely on imports in the shortage of patents. Under these circumstances, it is important to design and source technologies for these new types of conductive organic polymers.

At present, Korea's international competitiveness in the flat display field is very helpful in the research and development of the flexible display field, but there is a difficulty in securing added value and securing raw materials due to the lack of original technology. In order to solve this problem, there is an urgent need for securing the source technology necessary for securing raw materials, and it is necessary to establish close cooperative relations with institutions that can develop useful devices from the developed raw materials.

The most common semiconductor material used in field effect transistors is amorphous silicon. As described above, the field effect transistor using organic material has reached a level that exceeds the device using amorphous silicon in terms of performance. Recently, however, development of devices using polysilicon, which has better performance than amorphous silicon, and further, devices using single crystal silicon or single crystal-like silicon are rapidly progressing. . However, there is an advantage that the organic transistor can be manufactured at room temperature or at a low temperature of at least 100 ° C. It is possible with a single process such as spin coating or vacuum deposition. In order to take advantage of these many advantages, I think some problems must be solved.

The organic transparent electrode for flexible display is in the stage of technology development that has not yet been established in the world, so the original technology development is expected to preoccupy the organic transparent electrode market, and ITO transparent electrode, which is mostly dependent on imports The effect of import substitution and reverse export is expected.

In addition, the organic transparent electrode material can be freely changed from 80 to 90% of light transmittance in the range of 80 to 90% of sheet resistance by adjusting the composition and thickness, so that not only flexible displays but also touch panels, digital paper, electromagnetic shielding materials, and planar heating elements It can be used as a static electricity suppressing material, and its ripple effect is very big technology.

The organic solvent-soluble polythiophene derivatives of the present invention are expected to improve the physical properties of the organic transparent electrode material, and also a printing method that can freely pattern the circuit is expected to be helpful in development.                         

Polymer polythiophene derivatives (PEDOT: polyethylenedioxythiophene) synthesized from monomer 3,4-ethylenedioxythiophene (EDOT) by chemical oxidation or electropolymerization in the mid-1980s have high electrical conductivity (about 300 S / cm). Although it has high permeability in the thin film or film state and stability in the oxidation state (no change for 1000 hours at 100 ° C in air), it has low solubility in water and organic solvents, so that its usefulness decreases and its solubility is increased. Research has continued to improve physical properties. In the early 1990s, Bayer AG sold a solution of nano-dispersed monomer 3,4-ethylenedioxythiophene in water solvent using polystyrene sulfonic acid (PSS) as a Baytron P product. However, it is a water soluble polymer and therefore its use is limited.

As described above, some research results have been reported for the application of polymers to conductive materials, but there is a need to develop organic solvent-soluble polythiophene derivatives. Although polyaniline and polythiophene-based nanoparticle dispersions are prepared, polythiophene-based conductive polymers do not have a source patent. Research on conductive films or coating films using commercially available conductive polymers has been conducted for suppressing static electricity generation and blocking electromagnetic waves, but has not realized electrical conductivity compared to light transmittance at the level of transparent electrodes.

In the current technology, a transparent electrode of 60 mA / sq at 90% transmittance has been developed, and research and development is being applied to the device as an electrode for a touch panel and a flexible display. At the same time, the development of a patternable printing solution for the use of a conductive polymer solution as a wiring material is underway.                         

Due to the increasing interest in flexible displays, research and development of each material and device of organic transistors are actively conducted in both academic and industrial fields, but research on electrode materials is relatively poor. Due to the lack of original patents for commercially available conductive polymer materials, polyaniline or polythiophene-based polymer dispersions have no choice but to depend on imports, and improve the conductivity and patterning methods of these conductive polymers to develop transparent electrodes and wiring. The research and development to apply as a material is also not made a variety. Nevertheless, the organic transparent electrode in Korea has reached the world's highest level, although it can be used as a touch panel electrode, and the patterning method of the transparent electrode will be developed soon.

The high international competitiveness of Korea's flat panel display field is a great help in the research and development of the flexible display field. However, the limited number of companies related to electrode parts and components is an obstacle to developing transparent electrodes and wiring materials. . Improvement of light transmittance and electric conductivity is important for the smooth development of electrode material, but it is also important to support substrate and substrate surface treatment technology, printing technology and equipment that can thin the film. Currently, there are few companies in Korea that have source technology that is not application technology related to conductive polymers, and there is a lack of infrastructure to make parts. Nevertheless, the development of compositions that exhibit electrical conductivity relative to the highest level of light transmission among transparent electrode materials known to date will help enhance the national competitiveness of flexible displays.

The present invention seeks to provide a process for the preparation of organic solvent soluble polythiophene derivatives.

The present invention also provides a transparent electrode to which the organic solvent soluble polythiophene derivative is applied.

The present invention also provides a field effect transistor to which the organic solvent soluble polythiophene derivative is applied.

Another object of the present invention is to provide a method for synthesizing monomers of organic solvent-soluble polythiophene derivatives.

The present invention is a poly (3,4-alkoxythiophene) derivative represented by the following general formula (I) or a poly (3,4-ethylenedioxythiophene) represented by the general formula (II), which can be dissolved in an organic solvent. Provided are methods for preparing the derivatives.

Wherein R ₁ is a C ₅ to C ₁₈ long chain alkyl group, a cycloalkyl group, and an ethylene oxide substituent, and R ₂ is the same as R ₁ or a derivative of -OR and -NR and -OAr or -NAr. Aromatic substituents may be included.)

The organic solvent soluble high molecular compound represented by the general formula (I) according to the present invention reacts the 3,4-dioxythiophene ester compound represented by the following general formula (III) with the compound represented by the following general formula (IV) Obtaining the compound represented by the following general formula (V), and obtaining the compound represented by the following general formula (VI) from the compound represented by the general formula (V), and then from the compound represented by the general formula (VI) After obtaining the monomer represented by (iii), it can manufacture by superposing | polymerizing the monomer represented by general formula (iii).

(Wherein R ₁ is a C ₅ to C ₁₈ long chain alkyl group, a cyclo alkyl group, and an ethylene oxide substituent, and X is a halogen or a hydroxy group.)

3,4-dihydroxythiophene-2,5-dicarboxylic acid, which is a compound represented by formula (III), used in the preparation method of the present invention is a thiodiglycolic acid as a starting material, as in the above scheme. Synthesized by Sahasrabudhe et al . In 1959 [Sahasrabudhe et al, Nature, Lond. 184 (1959) 202, and derivatives thereof can be prepared by a method synthesized by Gogte et al. In 1967 (Gogte et al, Tetrahedron 23 (1967) 2437).

For example, the dicarboxylic acid ethyl ester derivative represented by the general formula (III) is synthesized ethyl ester under sulfuric acid catalyst using thidiglycolic acid as starting material, and then ethanol solvent, ethoxy sodium Diethyloxalate may be reacted under (NaOEt) base to synthesize 3,4-dihydroxythiophene dicarboxylic ester sodium salt, followed by acidification, to prepare diol compound (III).

Furthermore, by reacting the compound (III) with the compound (IV) under salt conditions of potassium carbonate or sodium carbonate, a 3,4-alkoxy or diaryloxythiophene-2,5-diethyl ester compound (V) was synthesized. 3,4-dihydroxythiophene-2,5-dicarboxylic acid (VI) may be prepared by hydrolysis in an aqueous solution of sodium hydroxide (NaOH) or potassium hydroxide (KOH) or an alcohol solution.

Decarboxylation of 3,4-dialkoxy or diaryloxythiophene compounds, which are monomers represented by general formula (VII), using copper chromite and quinoline of dicarboxylic acid represented by general formula (VI) It can manufacture by.

The monomer represented by the general formula (VII) is prepared by the above-described method, and various kinds of polymer synthesis methods, for example, iron (III) chloride (FeCl ₃ , A. Kumar, et al, Macromolecules 1996, 29 , 7629) or tritoluene selfonated iron (III) [Fe (OTs) ₃ , Literature: DM de Leeuw, et al, Synth. Met. 1994, 66 , 263], Oxidative Chemical Polymerization using Electrochemical and Electrochemical Polymerization using electricity. Literature: Q. Pei, et al, Polymer 1994, 35 , 1347) and transition metal-mediated polymerization using transition metals by substituting dihalogens for monomers. Literature: T. Yamamoto, et al, Synth. Met 1999, 100 , 237) and the like can be used to prepare the organic solvent soluble polymer (I).

In addition, the organic solvent soluble polymer compound represented by the general formula (II) according to the present invention to prepare a compound represented by the general formula (III) in the same manner as described above and is represented by the general formula (VI) A 1,2-dihalogen compound or 1,2-dihydroxy compound is reacted to obtain a compound represented by the following general formula (VII), and represented by the following general formula (VII) from a compound represented by the general formula (VII) After obtaining the compound, a monomer represented by the following general formula (VII) can be prepared by decarboxylation using Quinoline and copper chromite from the compound represented by the general formula (VII). The monomer can be polymerized by the various kinds of methods described above to produce the organic solvent soluble polymer (II).

(Wherein R ₂ may be the same as R ₁ or may include aromatic substituents of a series of derivatives of —OR and —NR and —OAr or —NAr. In addition, X refers to a halogen or a hydroxyl group.)

As a compound represented by the above general formula (IV) that can be used in the present invention, for example, a monohalogen derivative (1-Haloalkanes derivative) includes 1-Bromohexane, 1-Bromooctane, 1-Bromodecane, 1-Bromododecane, And compounds such as 1-Bromotetradecane, 1-Bromohexadecane, 1-Bromooctadecane, 1-Bromodocosane, 2-Bromoethyl ether derivatives, or Amino acid-2- (2-bromoethoxy) ethyl ester derivatives represented by the following general formulas,

As the compound represented by the general formula (VI) that can be used in the present invention, for example, dihalogen derivatives (1,2-Dihaloalkanes derivatives) include 1,2-Bromohexane, 1,2-Bromooctane, 1, 2-Bromodecane, 1,2-Bromododecane, 1,2-Bromotetradecane, 1,2-Bromohexadecane, 1,2-Bromooctadecane, 1,2-Bromodocosane, etc. These derivatives are obtained by purchase or by bromination to 1-alkene Can be.

Also suitable as compounds represented by the general formula (VI) that can be used in the present invention, for example, symmetric dihalogen derivatives are 3,4-Dibromohexane, 2,5-Dibromo-3,4-hexanedione, 2 , 3-Dibromo-1,3-diphenyl-1-propanone, 7,8-Dibromobicyclo [4.2.0] octa-1,3,5-triene, 1- [1,2-Dibromo-2- (3,5 -dimethylphenyl) ethyl] -3,5-dimethylbenzene and 1-Cyclodecene, 1-Cyclododecene, (5E) -5-Decene, (7E) -7-Tetradecene and the like can be obtained by bromination. Dihydroxy compounds also belong to this.

The organic field effect transistor (OFET) of the present invention is a semiconductor thin film on the insulating substrate (Substrate) as shown in Figure 1 is represented by the general formula (I) or (II) of the present invention It can be defined as an organic thin film transistor (TFT) constructed using a polythiophene derivative.

Like other transistors, an organic field effect transistor (OFET) is a device with three terminals: a gate electrode, a drain, and a source. The main functions are switching and amplification. The principle of operation of an organic field effect transistor (OFET) is very similar to that of a metal oxide semiconductor FET (MOSFET). However, the MOSFET operates in a state where the minority carrier channel is inverted at the interface between the semiconductor layer and the gate insulating layer by the voltage applied to the gate electrode. However, the TFT has a large number of carrier channels accumulated at the interface. It works in the formed state. Thin film transistors (TFTs) are also applied to SRAMs and ROMs, but their primary applications are pixel switching devices in active matrix flat panel displays. TFT is used as a switching element or a current driving element of a liquid crystal display (LCD) or an organic electroluminescence display (OELD) pixel. The TFT used as the switching element makes each pixel independent from the electrical influence of the surrounding pixels and plays a role of transmitting electrical signals to the pixels. Currently, amorphous silicon (a-Si) and polycrystalline Si (poly-Si) are mainly used as TFTs, and recently, organic semiconductors such as pentacene and thiophene oligomers are also used. have.

The field effect transistor of the present invention uses a multiconjugated bisbenzimidazole derivative as an organic semiconductor in this active layer. The organic field effect transistor (OFET) is basically a transistor for controlling the on / off state between the drain and source two terminals in accordance with the voltage supply to the gate, the third electrode. In the Off operation, there is no current flow between the drain and the source two terminals. In the On operation, the current flows smoothly. When the gate voltage is above a certain voltage (threshold voltage), the transistor is turned on.

The operation region of the TFT is divided into two regions, a linear region and a saturation region, similarly to a MOSFET used as a DRAM (Dynamic Random Access Memory) memory device. When the drain voltage is small, the drain current is proportional to the drain voltage since the characteristic between the drain and the source basically exhibits ohmic characteristics. When the drain voltage is increased and the gate voltage is neutralized, the channel disappears from the drain side (Pinch Off), and the drain current does not increase any more and has a constant value regardless of the increase of the drain voltage.

Performance indexes for evaluating device characteristics of field effect transistors (FET) include field effect mobility (μ _FET (cm2 / Vs)) and threshold voltage (V _T). (V)] Current flicker ratio ( I _on / I _off ratio). First of all, the field effect mobility is the most important factor of the transistor's performance and represents the distance traveled by the unit electric field 1V / cm, and is determined by various scattering factors (impurity scattering, particle scattering, etc.).

Field effect mobility is the drain current versus source-drain voltage (I _D vs. V _DS ) can be calculated from the curve. The drain current is expressed by the following equations (1) and (2) for the linear and saturation regions of the drain current versus source-drain voltage curve, where μ is the field effect mobility, W is the width of the channel, L is the length of the channel, C _i is the capacitance per unit area of the gate insulator. V _G and V _T represent the gate voltage and the threshold voltage, respectively. At this time, plot the relationship graph of drain current vs. gate voltage (I _D -V _G ) from the drain current vs. source-drain voltage curve and apply them to equations (3) and (4) indicating their slopes in the linear and saturation regions. We can obtain the field effect mobility of.

In the case of inorganic (amorphous silicon) transistors, the required mobility is generally 1 to 10 cm 2 / Vs. The transistors using conjugated polymers reported to date are manufactured using poly (3-hexylthiophene) as an active layer, and have the highest value of 0.1 cm 2 / Vs. The threshold voltage is determined by the work function difference between the gate and the organic semiconductor, the internal charge and the interfacial charge of the gate insulating film. When the drain current versus gate voltage (I _D -V _G ) is graphed, the intercept on the x-axis becomes the threshold voltage.

The current blink ratio is an important figure of merit when driving a device and increases as the current flowing in the off- state decreases. The current in the interrupted state is represented by equation (4). Where σ is the electrical conductivity, t is the thickness of the active layer, and N _A is the doping dynamics. Therefore, the current in the blocking state is low when the electrical conductivity is low, the thickness of the active layer is thin, and the doping concentration is small. In the case of the inorganic transistor, the required current blink ratio is 10 ⁷ or more. The use of conjugated polymers in the active layer is still below that level, but the use of poly (3-hexylthiophene) results in current flash rates up to> 10 ⁶ .

Fabrication of the organic monomolecular field effect transistor is performed by contacting the substrate (Substrate 1), the gate (Gate) 2 formed on the substrate 1, and the gate 2 electrode as shown in FIG. An insulating film 3, an organic semiconductor thin film 4 formed in contact with the gate insulating film 3, and at least one pair of source-drains formed in contact with the organic semiconductor thin film 4. -drain) electrode (5). To illustrate this in more detail, the overall structure is not much different from a silicon-based transistor. When a voltage is applied to the gate, a current is not flown due to the insulating layer, and an electric field (electric field) is applied to the semiconductor, which is called a field effect transistor. The current flowing through the device is obtained by applying a voltage between the source and the drain, where the source is grounded to serve as a source of electrons or holes. The layer indicated thereon is an organic semiconductor layer.

Referring to the operation principle of the device centering on the p-type semiconductor, if the voltage is not applied to the source, drain, and gate first, all the charges in the organic semiconductor is evenly spread in the semiconductor. At this time, when a current is applied by applying a voltage between the source and the drain, a current proportional to the voltage flows under a low voltage. If a positive voltage is applied to the gate, all of the positive charge holes are pushed up by the electric field caused by the applied voltage. As a result, a layer free of conductive charges is formed near the insulator, which is called a depletion layer. In this situation, applying a voltage to the source and drain will reduce the conduction charge carriers, which will result in a lower amount of current than when no voltage is applied to the gate. On the contrary, when a negative voltage is applied to the gate, a positive charge is induced between the organic material and the insulator by the effect of the electric field due to the applied voltage, and thus a high amount of charge layer is formed in the portion close to the insulator. This layer is called an accumulation layer. At this time, if current is measured by applying voltage to the source and drain, more current can flow. Therefore, the amount of current flowing between the source and the drain can be controlled by alternately applying a positive voltage and a negative voltage to the gate while a voltage is applied between the source and the drain. This ratio of the amount of current is called an on / off ratio. In order to be a transistor device of good performance, this flashing ratio must be large.

As a substrate material, a thin glass material and a plastic material are used, and the glass used for the LCD uses a soda lime type and an alkali free type, which are also used as general window glass. In recent years, LCD applications are mainly used for small applications, taking advantage of light weight and thinness, and are used in watches, card type calculators, portable micro pagers, PDAs, mobile phones, and notebook computers. As the development is progressing, researches on displays such as organic TFT and OLED using plastic substrates that can realize this demand have been actively conducted worldwide, and research on the stability of these devices is also vigorous. In particular, in the case of the organic TFT, its properties are greatly changed by moisture and oxygen present in the air, and a high functional protective film is essential to obtain stable device characteristics. In addition, organic materials are known to react very sensitive to temperature, and research on this is being conducted.

Indium-tin oxide is mainly used as a gate configured on the substrate. The surface work function of ITO is slightly increased from 0.5 eV to 1.0 eV due to contamination of the substrate surface and adhesion of moisture. The purpose of the pretreatment technology of ITO substrate is to make the surface potential of ITO as close as possible to the surface potential of HTL so that holes can move more smoothly from the ITO used as the anode to the light emitting layer. The following three methods are mainly used for pretreatment of ITO substrates. It can be selectively applied according to the state of the substrate in three ways: surface oxidation method using glow discharge, ITO surface oxidation method using ozone generated by UV light source, and ITO surface oxidation method using oxygen radical generated by plasma. Whichever method is used, it is important to prevent the escape of oxygen from the ITO thin film, to remove moisture or organic matter formation from the surface and to oxidize the surface to obtain a work function appropriate for the interface between the ITO layer and the HIL layer. .

By far the most common dielectric (or insulator) used in devices is SiO ₂ . This is considered to be because it can be easily formed on Si, which has high insulation rate and is most often used as a substrate. However, because it is an amorphous structure and the dielectric constant is not as high as 3.9 it is difficult to see the optimal dielectric. As a trend of research, the use of plastic substrate is expected. First, thin film formation should be possible at low temperatures. This is because it is difficult to raise the temperature due to the low glass transition temperature (near 80 ° C in the case of PET). And the permittivity must be large.

The operation principle of the field effect transistor is to apply a voltage to the gate, which causes charges to accumulate across the dielectric, and the electric fields (fields) from these charges create an accumulation layer and a depletion layer. Thus, a high dielectric constant means that a lot of charge can be collected across the dielectric even at low voltages, and in other words, the device can be driven at low voltages. In addition to the dielectric constant, the insulation properties should be good. Since leakage current acts to neutralize the charge collected across the dielectric, it causes driving problems that cannot be maintained for a long time and must be refreshed frequently. In addition, the coefficient of thermal expansion should be the same or similar to the substrate. Due to the nature of the device, current flows inevitably because of the current. To withstand this heat well, materials with similar thermal expansion rates would be ideal. In addition, there should be no cracking in a certain degree of bending in order to be applied on a plastic substrate that can be bent. Recently, many acrylic polymers that are cured by heat or ultraviolet rays have been used in Korea.

It is applied by the principle of forming the insoluble polymer film by cross-linking when it is deposited by rotating coating to increase the temperature or irradiate UV rays. However, when the heat is used, the substrate may be bent due to the difference in thermal expansion rate with the plastic substrate, and the problem of patterning is difficult.

Thin film formation of the organic monomolecule is sequentially formed on the surface of the substrate using a vacuum deposition method in a high vacuum state of 10 ^-5 torr level. The vacuum chamber where these thin films are deposited consists of an evaporation source of the material, a film thickness control sensor, a device capable of precisely aligning the glass substrate and the metal shadow mask, and a power supply for evaporating the material. . Most of the organic materials used have higher vapor pressure, wider evaporation temperature range (100 ~ 500 ℃) and different evaporation temperatures compared to inorganic materials, so precise temperature control for each material is essential. The organic evaporation source is generally a ceramic crucible having a high thermal conductivity, and should be designed and manufactured so that organic matters can be splashed because it can be controlled stepwise and continuously. When the temperature of the evaporation source is not properly raised, the organic material that reaches the evaporation temperature in an excessively short time is splashed, and the inlet of the organic material evaporation source is blocked. As a result, the deposition rate of the organic material is changed to obtain the desired thin film characteristics. It is discolored or discolored during this deposition and cannot be used again.

In addition, each organic material is sublimated and melted for evaporation depending on the material, and each of them has different evaporation properties, so the ability to control the optimal evaporation conditions for each material is very important. . The organic thin film layer needs a device capable of mechanical alignment (± 200 microns) using an open mask. It should be configured as a separate independent chamber for depositing organic materials to minimize cross contamination and ensure high productivity.

At least one pair of source-drain electrodes formed in contact with the organic semiconductor thin film generally uses gold. This is because it is easy to deposit by vacuum thermal evaporation, but also has a high work function, so that holes can be easily injected into the p-type organic semiconductor. However, in the case of forming a thin film by spin coating a polymer thin film on the gold thin film, the adhesion between the polymer film and the gold thin film is poor, which may act as an additional resistance, thereby deteriorating the device characteristics.

Therefore, it is necessary to develop materials and processes having good conductive properties, high work functions, and excellent adhesion to organic materials. Recently, a paper on the interfacial properties between pentacene and gold, an organic semiconductor, was investigated using XPS and UPS. Experimental results in this paper show that there is no chemical bond between gold and pentacene, but only physical force, regardless of the order of pentacene and gold deposition. This tells us that no matter how we combine the two materials, there is no ohmic contact. This appears to be a phenomenon in which the current does not increase linearly at a low drain voltage in the transistor characteristic curve. In addition, since the charge is not effectively injected from the electrode to the organic semiconductor, the amount of current is reduced, and thus the charge mobility is also low.

In the case of p-type, the work functions of gold and organic semiconductors are almost the same, so only the contact problem needs to be solved. However, in the case of n-type, the difference in work function is so large that a technique is needed to shift the metal work function . In order to solve this phenomenon, a method of fabricating an organic monomolecular film on a metal surface by self-assembly and then depositing an organic semiconductor thereon has been attempted. This monomolecular film forms covalent bonds through chemical bonds with gold metals, and easily forms ohmic contacts by bonding organic materials with upper organic semiconductors so that charges can be easily injected from metal electrodes to organic semiconductors as a whole. .

The field effect transistor of the present invention uses a thin plate coated with indium tin oxide (Indium-Tin Oxide) as a gate to glass as a substrate, a gate insulating film (Insulator) formed in contact with the gate electrode, and the gate In an organic field effect transistor having an organic semiconductor thin film (Semiconducting materials) formed in contact with the insulating film and at least a pair of source-drain electrodes formed in contact with the organic semiconductor thin film, the organic semiconductor thin film is a general in accordance with the present invention It is characterized by being formed from the polythiophene derivative represented by Formula (I) or General formula (II).

In the field effect transistor of the present invention, the polythiophene derivative represented by the general formula (I) or (II) is used as the organic semiconductor in the active layer of FIG. Substrate (Substrate), and the gate (Gate (ITO)) is configured on the substrate, a gate insulating film (Insulator) that is configured in contact with the gate electrode, an organic semiconductor thin film (Semiconducting materials) consisting of in contact with the gate insulating film and In an organic field effect transistor having at least a pair of source-drain electrodes configured to be in contact with the organic semiconductor thin film, the organic semiconductor thin film is represented by the general formula (I) or the general formula (II) according to the present invention. Characterized in that it is formed of a polythiophene derivative.

In addition, the organic transparent electrode for the flexible display (Transparent Organic Electrode for Flexible Display) is an organic semiconductor material other than ITO (Indium Tin Oxide) on an insulating substrate (Substrate), as shown in FIG. It can be defined as an organic organic transparent electrode that can be circuitized using a polythiophene derivative represented by the general formula (I) or (II).

The information display is expected to come from the CRT, go through LCD and PDP, and come to the age of flexible display which is the dream display. In order to produce a flexible display that can be folded or bent, not only the development of the substrate material but also the development of a flexible electrode material having excellent light transmittance and electrical conductivity must be made.

Currently, ITO (Indium Tin Oxide) transparent electrodes are used for flat panel displays that use glass substrates such as LCD and PDP.In order to make ITO transparent electrodes, expensive equipment such as vacuum deposition and etching and corrosive chemicals are used. As it should be, not only economic efficiency is low, but also side effects such as environmental pollution.

Flexible display should replace the existing glass substrate with a transparent and flexible plastic substrate. When ITO transparent electrode is used on the plastic substrate, the sheet resistance increases due to the deformation caused by the difference in thermal expansion coefficient with the substrate, and is easily broken by external impact. Problems may arise.

In order to solve this problem, researches on using a conductive polymer as an organic material as a transparent electrode material have been conducted. However, since most of the conductive polymers developed in foreign countries absorb light in the visible range, light transmittance is 80 At%, the sheet resistance is very high above 500 mA / sq, which is not suitable for use in flexible displays.

The organic transparent electrode, which is currently being developed, improves the light transmittance and electrical conductivity of a coating film by controlling the fine phase structure of the film by controlling the doping state of polythiophene-based conductive polymer nanoparticles and introducing an additive. When coated on the substrate, it is possible to manufacture an organic transparent electrode having a light transmittance of 80% or more and a sheet resistance of 300 mW / sq or less in the visible light region including the substrate.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

1 is a cross-sectional view of a field effect transistor (FET) using an organic soluble polythiophene polymer according to the present invention,

FIG. 2 is a transparent electrode circuit diagram using an organic soluble polythiophene polymer, and an organic solvent soluble polythiophene derivative represented by various kinds of general formulas (I) and (II) synthesized by the method in the following [Example 7] Using a compound as a semiconductor device (Semiconducting materials) is an example of manufacturing a circuit for a transparent electrode of the structure shown in Figure 2 using an inkjet print.

3 is a solubility curve of organic soluble polythiophene polymers and PEDOT, and FIG. 3 shows general formulas (I) and (II) synthesized in [Example 7] with organic semiconductor materials in the same manner as in [Example 8]. The solubility and electrical conductivity of the organic solvent-soluble polythiophene derivative compound represented by) in various organic solvents were measured and compared with PEDOT to obtain the results as shown in [Table 1]. .

The solubility of the alkoxy polymer compounds having 10, 12, 14, 16, and 18 carbon atoms than that of PEDOT in organic solvents having a polarity of 0 to 5 (n-hexane, chloroform, tetrahydrofuran, ethyl acetate) is higher than that of PEDOT. It can be seen that in the organic solvents (ethanol and dimethylformamide) having a polarity of 5 or more, almost all polymers are hardly dissolved.                     

In addition, it can be seen that among the alkoxy polymer compounds having 10, 12, 14, 16 and 18 carbon atoms, the solubility of the polymer compound having 12 carbon atoms is excellent.

In addition, in the case of electrical conductivity, alkoxy polymer compounds having 10, 12, 14, 16 and 18 carbon atoms were better than PEDOT, and among them, it was found that the highest electrical conductivity of the polymer compound having 16 carbon atoms.

4A and 4B are resistance / voltage (IV) characteristic curves for R ₁ of-(CH ₂ ) ₁₁ CH ₃ } derivative in poly (didodecyloxythiophene) {[formula II].

4A and 4B are graphs (I / V curves) obtained by converting a voltage between a source and a drain from 0V to -50V for each gate voltage when converting a gate voltage from 0V to -5V.

When the negative voltage is applied from the resistance / voltage (IV) characteristic curve as shown in FIGS. 4A and 4B, the I / V curve is derived from the negative region. Therefore, the charge carrier of the organic semiconductor material is positively charged, that is, a hole. Visible. Therefore, the material used in this device material was confirmed to be a p-type material.

FIG. 5 is an UV-Vis./NIR Spectra for polythiophene derivative compounds. This can be seen whether the use as an organic polymer transparent electrode.

FIG. 5 is an ultraviolet-visible light ray of an alkoxy polymer compound derivative compound having PEDOT and C 10, 12, 14, 16, and 18 synthesized in [Example 7] as an organic semiconductor material in the same manner as in [Example 8] It is a graph obtained by examining the near-infrared spectrum (UV-Vis./NIR Spectra).

For monochromatic light, red (700-610 nm), orange (610-590 nm), yellow (590-570 nm), green (570-500 nm), blue (500-450 nm), violet (450-400 nm) It is expressed in the area of, and the color of the material is composed of orange and red (also shown in a little yellow), so the transmittance in the area of about 700 ~ 570nm can be observed.

In addition, the transmittance in the above-described region has a high transmittance of 90% or more, and shows that the electrical conductivity is about the semiconductor level.

Example 1 Synthesis of "Diethyl 3,4-dihydroxythiophene-2,5-ticarboxylester" represented by General Formula (III)

Synthesis of the above compound was synthesized in three steps as follows.

<Step 1>: Synthesis of Diethyl Thioglycolate

In a round-bottom flask (1 L), 50 g (333 mmol) of thiodiglycolic acid was dissolved in anhydrous ethanol (250 mL), and concentrated sulfuric acid (20 mL) was slowly added thereto, followed by stirring under reflux. The mixture was refluxed for 24 hours until all of the starting materials reacted. Then, the mixture was poured into iced water (300 mL) to terminate the reaction. The mixture was extracted three times with diethyl ether (200 mL), and the combined organic layers were washed with saturated aqueous sodium carbonate solution and water. After drying over magnesium sulfate, the solvent was removed under reduced pressure to obtain a crude product (VI, 59.8 g, 87%). Purity was measured by gas chromatography / mass selective detector (GC / MSD) and used immediately for the next reaction.                     

GC / MSD retention time (min) 7.79, (m / z) 60, 70, 77, 88, 105, 115, 121, 133, 149, 160 (100), 177, 206 (M ⁺ ), purity> 99%

<Step 2>: Synthesis of Diethyl 3,4-dihydroxythiophene-2,5-dicarboxylate disodium salt

37.9 g (558 mmol) of NaOC ₂ H ₅ was dissolved in anhydrous ethanol (300 mL) in a round-bottomed flask (1 L), and diethyl thioglycolate (VI) synthesized in [Example 1] at 0 ° C. A solution of 25.3 g (VI, 123 mmol) and 45.1 mL (332 mmol) of diethyl oxalic acid was slowly added dropwise. After allowing the temperature to rise slowly, the mixture was stirred under reflux for 2 hours until all of the starting materials reacted. The solution was allowed to stand at room temperature until the resulting yellow precipitate was filtered off, washed with anhydrous ethanol and dried to give the crude product which was used directly in the next reaction.

<Step 3>: Synthesis of Diethyl 3,4-dihydroxythiophene-2,5-dicarboxylate (III)

In a Erlenmeyer flask (500 mL), 37.4 g (VII, 123 mmol) of sodium salt compound are suspended in 200 mL of water and acidified with concentrated hydrochloric acid (20 mL) at 0 ° C. Stirring for about 1 hour to completely dissociate gave 20.8 g of diol precipitate (VIII, total of 65% in 2-3 steps).

GC / MSD retention time (min) 15.18 (m / z) 60, 70, 77, 88, 105, 115, 121, 133, 149, 160 (100), 177, 260 (M ⁺ )

¹ H NMR (300 MHz, CDCl ₃ , TMS) δ 1.36 (t, J = 7.14 Hz, 6H, CH ₃ x 2), 4.33 (2H x 2, q, J = 7.14 Hz), 4.39 (4H, m)

¹³ C NMR (75 MHz, CDCl ₃ , TMS) δ64.3, 65.2, 110.7, 141.7, 180.1 (left-right symmetry)

Example 2 Synthesis of Diethyl 3,4-ditetradecyloxythiophene-2,5-dicarboxylate [V in R ₁ to-(CH ₂ ) ₁₃ CH ₃ ]

In a round-bottomed flask (250 mL), 7.00 g (III, 27 mmol) of diol compound and 16.47 g (17.68 mL, 59.40 mmol, 2.2 eq) of 1-bromotetradecane were dissolved in dimethylformamide (DMF, 100 mL). 8.2 g (59.50 mmol, 2.2 eq) of potassium carbonate was added and the mixture was stirred under reflux for 48 hours until all the starting materials reacted. The solution was cooled to room temperature and poured into iced water (200 mL) to terminate the reaction. The mixture was extracted with ethyl acetate (100 mL, 2 times), washed with brine and water, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure to obtain a crude product (IX, 13g). ) Recrystallization with anhydrous ethanol afforded 11.65 g (IX, 63%) of pure compound.

¹ H NMR (300 MHz, CDCl ₃ , TMS) δ0.88 (t, J = 6.59 Hz, 6H, CH ₃ x 2), 1.21-1.28 (m, 40H, CH ₂ x 20), 1.37 (t, J = 7.04 Hz, 6H, CH ₃ x 2), 1.40-1.49 (m, 4H, CH ₂ x 2), 1.70-1.79 (m, 4H, CH ₂ x 2), 4.14 (t, J = 6.60 Hz, 4H, CH ₂ x 2), 4.34 (q, J = 7.14 Hz, 4H, -OCH ₂ x 2)

Example 3 2- (6-carboxyhexyl-3-octyl-2,3-dihydrothieno [3,4-b] -1,4-dioxin-5,7-dicarboxylic acid { 2- (6-Carboxyhexyl) -3-octyl-2,3-dihydrothieno [3,4-b] [1,4] dioxine-5,7-dicarboxylic acid diethyl ester} [In VIII, R ₂ is-(CH ₂ ) ₇ CH ₃ and R ' ₂ is-(CH ₂ ) ₇ COOH] Synthesis

9,10-dibromoocta obtained from 1.00 g (III, 3.86 mmol) of the diol compound and Khan, NA et al. Organic Syntheses (1957), 77-9] in a round-bottomed flask (250 mL). Dissolve 1.65 g (3.86 mmol) of dibromooctadecanoic acid in dimethylformamide (DMF, 40 mL) and add 1.17 g (8.49 mmol, 2.2 eq) of potassium carbonate for 48 hours until all the starting materials react. Stirred at reflux. The solution was cooled to room temperature, poured into iced water (80 mL) to terminate the reaction, extracted with ethyl acetate (50 mL, twice), washed with brine and water, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure to obtain a crude product (IX, 1.5). g) was obtained. Recrystallization with anhydrous ethanol gave 874 mg (43%) of pure compound.

Example 4 2,3-bisdecyl-2,3-dihydrothioene- [3,4-b] -1,4-dioxin-5,7-dicarboxylic acid {2,3- Bisdecyl-2,3-dihydrothieno [3,4-b] [1,4] dioxine-5,7-dicarboxylic acid diethyl ester} [Synthesis of R ₂ by-(CH ₂ ) ₉ CH ₃ ] in VIII

In a round-bottom flask (250 mL), 1.00 g (III, 3.86 mmol) of diol compound and 1.32 g (3.86 mmol) of 11,12-docosanediol were dissolved in tetrahydrofuran (THF, 20 mL) and tributyl Phosphine (TBP, 1.95 g, 2.40 mL, 9.65 mmol, 2.5eq) was added and diisopropylazodicarboxylate (DIAD, 1.95 g, 1.90 mL, 9.65 mmol, 2.5eq) was added at room temperature for 30 minutes. Slowly dropwise over. Stir at 40 ° C. for 48 hours until all starting materials reacted. After removing the solvent under reduced pressure, n-hexane (10 mL) was poured into the yellow oily solid, and the precipitate was obtained by filtration. The crude product was subjected to silica gel column separation (n-hexane: ethyl acetate = 10: 1), followed by ethyl. Recrystallization from acetate gave 1.14 g (52%) of the pure monomer compound.

Example 5 Synthesis of 3,4-ditetradecyloxythiophene-2,5-dicarboxylic acid [R ₁ to-(CH ₂ ) ₁₃ CH ₃ in VI]

In an Erlenmeyer flask (250 mL) with 5.08 g (10 mmol) of diethyl 3,4-ditetradecyloxythiophene-2,5-dicarboxylate [R ₁ in-(CH ₂ ) ₁₃ CH ₃ ] 10% KOH aqueous solution (50 mL) was added thereto, and the mixture was stirred under reflux for 1 hour. The solution is brought to room temperature, the suspension is filtered off, and the filtrate is acidified with 2 molar aqueous hydrochloric acid solution at 0 ° C. The mixture was stirred for about 1 hour to completely dissociate to give 6.2 g of a dicarboxylic acid precipitate. This precipitate was recrystallized from anhydrous methanol to give 5.41 g (86%) of white needles.

¹ H NMR (300 MHz, DMSO-d ₆ , TMS) δ 0.83 (t, J = 6.63 Hz, CH ₃ x 2), 1.20-1.28 (m, 40H, CH ₂ x 20), 1.35-1.42 (m, 4H, CH ₂ x 2), 1.57-1.69 (m, 4H, CH ₂ x 2), 4.06 (q, J = 6.59 Hz, -OCH ₂ x 2)

Example 6 Synthesis of 3,4-didodecyloxythiophene [R ₁ to-(CH ₂ ) ₁₁ CH ₃ in VII (Decarboxylation)

Quinoline containing 4.00 g (III, 7.00 mmol) of 3,4-didodecyloxythiophene-2,5-dicarboxylic acid compound and 4% copper chromite (1 g) as catalyst in a round bottom two-necked flask (250 mL) After adding (25 mL), the mixture was heated and stirred at 180 ° C. for 10 hours. After all of the starting materials reacted, the mixture was cooled to room temperature and the suspended solids were removed by filtration through celitefh and washed with 1M aqueous hydrochloric acid. The filtrate was extracted with ethyl ether (30 mL, 5 times), washed with brine and water, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure to obtain a crude product (3.2 g). The crude product was purified by silica gel column separation (n-hexane: ethyl acetate = 20: 1) and recrystallized with ethyl acetate to obtain 1.90 g (IX, 56%) of a pure monomer compound.

¹ H NMR (300 MHz, CDCl ₃ , TMS) δ 0.98 (t, J = 6.78 Hz, CH ₃ x 2), 1.20-1.28 (m, 36H, CH ₂ x 18), 1.30-1.38 (m, 4H, CH ₂ x 2), 1.76-1.82 (m, 4H, CH ₂ x 2), 3.96 (t, J = 6.78 Hz, 4H, -OCH ₂ x 2), 6.15 (s, thiophene CH x 2)

The decarboxylation reaction can be obtained by heating to 200 ~ 250 ℃ without a catalyst, but there is a difficulty in yield and separation purification.

Example 7 Synthesis of Poly (didodecyloxythiophene) [R ₁ in-(CH ₂ ) ₁₁ CH ₃ ] in II

4.84 g (III, 1.00 mmol) of 3,4-didodecyloxythiophene monomer compound was dissolved in chloroform (50 mL) in a round bottom two-necked flask (100 mL), and then 5.4 g (2.00 mmol, 2eq.) Of oxidizing agent FeCl ₃ was dissolved. The solution dissolved in chloroform (20 mL) was added dropwise under nitrogen. The black polymer produced by stirring for 24 hours at room temperature was filtered, washed with methanol and dried in vacuo for 36 hours to obtain the product (4g).

In the above method, the amount of oxidizing agent was changed to 0.5 equivalent, 1 equivalent, 2 equivalent and 3 equivalent, and the result of experiment was the highest in high molecular weight, electrical conductivity and production rate.

Example 8 Fabrication of Field Effect Transistor                     

Using various kinds of organic solvent-soluble polythiophene derivative compounds represented by general formulas (I) and (II) synthesized by the method in Examples 1 to 7 as a semiconductor device (FIG. 1) A field effect transistor (electronic device) having the structure

Specifically, ITO-coated Glass was cut into 3cm / 3cm, and the glass plate was washed with ethanol / acetone / isopropyl alcohol / distilled water, and then the ketone tape (vacuum tape) was used as a gate on the glass plate. ) And 4 wt (wt)% PMMA was spin-coated at 2000 rpm on the glass plate. After the spin coating, the ketone tape was removed, and the glass plate was dried at 200 ° C. for 2 hours in an oven. When the glass plate was placed in the deposition apparatus and dropped below ⁵ × 10 ⁻⁵ torr, the organic material (synthesized in Synthesis Example 7) was thermally deposited using a shadow mask. At this time, the thickness was measured using a thickness monitor was 700nm. After the substrate was lowered to room temperature, a gold mask was thermally deposited to a thickness of 400 nm using a shadow mask to fabricate a field effect transistor (electronic device). After lowering to room temperature, the field effect transistor characteristics were investigated.

[Example 9]: Fabrication of well electrode

Using various kinds of organic solvent-soluble polythiophene derivative compounds represented by general formulas (I) and (II) synthesized by the method in Examples 1 to 7 as a semiconductor device (FIG. 2) Circuit for a well-known electrode having the same structure as that of

[Test Example 1]: Comparative tests of solubility, electrical conductivity and PEDOT of organic solvent-soluble polythiophene derivative compounds represented by General Formulas (I) and (II).

In the same manner as in [Example 8], the organic semiconductor material was prepared in various organic solvents of the organic solvent-soluble polythiophene derivative compounds represented by the general formulas (I) and (II) synthesized in [Example 7]. The solubility and electrical conductivity of PEDOT were measured and compared to PEDOT, and the results as shown in [Table 1] were obtained.

From the results of [Table 1] and [FIG. 3], the alkoxy polymer compounds having 10, 12, 14, 16, and 18 carbon atoms than PEDOT have an organic solvent having a polarity of 0 to 5 (n-hexane, chloroform, tetrahydrofuran). , Ethyl acetate) can be seen that the solubility is good and almost all the polymers are hardly dissolved in the organic solvent (ethanol and dimethylformamide) of polarity 5 or more.

In addition, it can be seen that among the alkoxy polymer compounds having 10, 12, 14, 16 and 18 carbon atoms, the solubility of the polymer compound having 12 carbon atoms is excellent.

In addition, in the case of electrical conductivity, alkoxy polymer compounds having 10, 12, 14, 16 and 18 carbon atoms were better than PEDOT, and among them, it was found that the highest electrical conductivity of the polymer compound having 16 carbon atoms.

Table 1 shows the electrical conductivity and solubility of the polymers having R ₁ of C ₁ 0, C ₁₂ , C ₁₄ , C ₁₆ and C ₁₈ in the general formula 1 synthesized by the method of PEDOT and [Example 7]. ) Is a comparison. Here, PS (partial soluble) represents 10-20% (volume / volume), SS (Sparing soluble) represents 5-10% (volume / volume), and IS (Insoluble) represents 0-5% (volume / volume).

[Test Example 2]: Electronic device characteristics test as field effect transistor material

In the same manner as in [Example 8], R ₁ is-(CH ₂ ) ₁₁ CH ₃ ] derivative of poly (didodecyloxythiophene) [II] synthesized in [Example 7] as an organic semiconductor material. The resistance / voltage (IV) characteristics were investigated.

When converting the gate voltage from 0V to -5V, the voltage between the source and the drain was converted from 0V to -50V for each gate voltage to obtain a graph (I / V curve) as shown in FIGS. 4A and 4B.

When the negative voltage is applied from the resistance / voltage (IV) characteristic curves of FIGS. 4A and 4B, the I / V curve comes out of the negative region. Therefore, the charge carrier of the organic semiconductor material appears to be a positive charge, that is, a hole. . Therefore, the material used in this device material was confirmed to be a p-type material.

Test Example 3 Electronic Device Characteristic Test as Transparent Electrode Material

Ultraviolet-visible / near infrared rays for the PEDOT synthesized in [Example 7] and the alkoxy polymer compound derivative compound having 10, 12, 14, 16, and 18 carbon atoms as organic semiconductor materials in the same manner as in [Example 8] The spectrum (UV-Vis./NIR Spectra) was examined to obtain a graph as shown in FIG. 5.

For monochromatic light, red (700-610 nm), orange (610-590 nm), yellow (590-570 nm), green (570-500 nm), blue (500-450 nm), violet (450-400 nm) It is expressed in the area of, and the color of the material is composed of orange and red (also shown in a little yellow), so the transmittance in the area of about 700 ~ 570nm can be observed.

The transmittance in the above-described area has a high transmittance of more than 90%, and shows that the electrical conductivity is about the semiconductor level.

The organic solvent soluble poly (3,4-alkoxythiophene) or poly (3,4-ethylenedioxythiophene) derivative prepared by the production method of the present invention may be used for electromagnetic wave shielding film, capacitor, organic EL display, etc. in addition to the field effect transistor. It is useful as organic monomolecules in organic thin film transistors, solar cells and memory devices using multiphoton absorption.

Claims (7)

In the method for producing an organic solvent soluble poly (3,4-alkoxythiophene) or poly (3,4-ethylenedioxythiophene) derivative, A 3,4-dioxythiophene ester compound represented by the following general formula (III) is reacted with a compound represented by the following general formula (IV) to obtain a compound represented by the following general formula (V), and a general formula (V) The compound represented by the following general formula (VI) was obtained from the compound represented by the following formula. Then, the monomer represented by the following general formula (VII) was obtained from the compound represented by the general formula (VI), and then represented by the general formula (VII). A method for producing an organic solvent soluble poly (3,4-alkoxythiophene) or poly (3,4-ethylenedioxythiophene) derivative represented by the following general formula (I), wherein the monomer is polymerized.

(Wherein R ₁ is a C ₅ to C ₁₈ long chain alkyl group, a cyclo alkyl group, and an ethylene oxide substituent, and X is a halogen or a hydroxy group.) In the method for producing an organic solvent soluble poly (3,4-alkoxythiophene) or poly (3,4-ethylenedioxythiophene) derivative, A 3,4-dioxythiophene ester compound represented by the following general formula (III) and a compound represented by the following general formula (VI) are reacted to obtain a compound represented by the following general formula (VII). After obtaining the compound represented by the following general formula (VII) from the compound represented by the following, synthesize | combining the compound represented by the general formula (VII), and then from the compound represented by the said general formula (VII) The organic solvent soluble poly (3,4-alkoxythiophene) or poly (3,4-ethylenedioxythiophene represented by the following general formula (II) characterized by superposing | polymerizing the monomer after obtaining the monomer represented by ) Preparation of Derivatives.

(Wherein R ₂ is the same as R ₁ or aromatic substituents of derivatives of -OR and -NR and -OAr or -NAr may also be included. X also refers to a halogen or a hydroxy group.) Substrate (Substrate), and a gate that is configured on the substrate (Gate, ITO) and, with the gate insulating film (Insulator) that is configured in contact with the gate electrode, and an organic semiconductor thin film (Semiconducting materials) consisting of in contact with the gate insulating film, An organic field effect transistor having at least a pair of source-drain electrodes configured to be in contact with the organic semiconductor thin film, The organic-solvent soluble poly (3,4-dialkoxythiophene) or poly () wherein the organic semiconductor thin film is represented by general formula (I) or general formula (II) produced by the production method according to claim 1 or 2 above. An organic field effect transistor, characterized in that formed of 3,4-ethylenedioxythiophene) derivative. The organic field effect transistor according to claim 3, wherein the substrate is one selected from silicon, glass or plastic. 4. The organic field effect transistor of claim 3, wherein the gate is indium-tin oxide (ITO) or antimony-tin oxide (ATO). The method of claim 3, wherein the gate insulating layer (Insulator) is one selected from organic materials consisting of BCB, Polyimid, Parylene, PMMA or CYPEdls, SiO ₂ , SiN _x , AlN, AlON, Al ₂ O ₃ , Ta ₂ O ₅ , La ₂ O ₅ , An organic field effect transistor, characterized in that one kind selected from inorganic substances consisting of BZT or PZT. Organic solvent-soluble poly (3,4-dialkoxythiophene) or poly (3,4-ethylene represented by general formula (I) or general formula (II) produced by the production method according to claim 1 or 2 above. A circuit for transparent electrodes, wherein a semiconductor element is formed of a deoxythiophene derivative.

Images