JP5012783B2 - Organic electronic device and manufacturing method thereof - Google Patents

Description

  The present invention relates to an organic material that can be used for an organic device and a device manufacturing process, and to a method for manufacturing a device such as a display, an integrated circuit, and a sensor.

  Field effect transistors are widely used as important switches and amplifying elements along with bipolar transistors. Until now, elements using silicon have been widely used. A field effect transistor has a structure in which a gate electrode is provided on a semiconductor material via a source and drain electrodes and an insulator layer. Basically, one of the p-type and n-type carriers transports a charge and is a typical monopolar device.

In particular, those using silicon dioxide (SiO ₂ ) called an MOS (Metal-Oxide-Semiconductor) structure as an insulator are widely used for memory elements, gate elements, and the like. In addition, those using amorphous silicon as a semiconductor can be manufactured as thin film transistors by forming a semiconductor layer on a substrate such as glass, and this is widely used in active matrix liquid crystal displays that are used as switching elements in each cell. Has been.

  The operational characteristics of such a field effect transistor are as follows: carrier mobility μ, conductivity σ of the semiconductor used, capacitance Ci of the insulating layer, element configuration (source-drain electrode distance L and width W, insulating layer Among them, the semiconductor material having a high mobility (μ) exhibits good characteristics.

  Among semiconductor materials, inorganic semiconductors typified by Si need to be processed at a high temperature of 300 ° C. or higher at the time of production, and it is difficult to use a plastic substrate or film for the substrate, and a lot of energy is required for production. . In addition, the element manufacturing process in a vacuum requires expensive equipment on the production line and is expensive. On the other hand, most of transistors using an organic material can be manufactured by a low-temperature process compared to an inorganic semiconductor. Therefore, a plastic substrate or a film can be used, and a light-weight element that is not easily broken can be manufactured. In addition, some devices can be manufactured using a solution coating or printing method, and a large-area device can be manufactured at low cost. Furthermore, since there are a wide variety of materials, and it is possible to easily change the material properties easily by changing the molecular structure, functions and elements that are impossible with inorganic semiconductors by combining different functions Can also be realized.

  Several transistors using such organic substances have been demonstrated so far. Examples thereof include those using conductive polymers and conjugated polymers as disclosed in JP-A-61-202467, and those using low molecular compounds disclosed in Japanese Patent No. 2984370. As examples of the conjugated polymer, attempts have been made to use a conjugated polymer as a semiconductor as it is and to perform switching by putting ions (dopants) in and out by an electric field. However, since it is a polymer material, it is difficult to purify, a defect derived from an incomplete part of the structure is formed at the time of film formation, and the oxidation potential is likely to be lowered and easily oxidized. No material with good performance and stability has been found.

  On the other hand, as an example of a low molecular weight compound, an organic transistor that exhibits mobility similar to that of a-Si by vapor deposition is shown, which is an aromatic condensed hydrocarbon such as pentacene or an oligothiophene having four or more thiophene rings connected. A low molecular weight compound is a stable material because it synthesizes a compound having a fixed structure and can use various purification methods such as sublimation purification, recrystallization, and column chromatography. On the other hand, the film-forming method by vapor deposition has a higher manufacturing cost than coating, and it is difficult to make full use of the characteristics of organic matter. In general, when a film is formed by applying a low molecular weight compound from a solution, a granular structure is formed by crystallization, so that it is difficult to obtain a uniform film and there are many problems in film forming.

  In recent years, various physical phenomena have been observed in transistors using single crystals of low-molecular compounds. Examples include laser oscillation by current injection, superconductivity, and quantum Hall effect. However, an organic single crystal is difficult to grow a large crystal, and is very soft. Therefore, it is extremely difficult to cut and polish it for use as a device.

  Among low molecular weight compounds, many applications of phthalocyanines to organic devices have been studied. For example, as an application to a field effect transistor, JP-A-11-251601, JP-A-2000-174277, Appl. Phys. Lett. 69 (1996) p3086. Phthalocyanines are generally insoluble in solvents, and in order to produce these devices, it is necessary to form a film by a vacuum deposition method.

On the other hand, as a method for producing a field effect transistor by applying a solution process using a low molecular weight compound and then converting it to a semiconductor, pentacene or a similar aromatic hydrocarbon system is described in Science 270 (1995) p972. , Optical Materials, Vol. 12 (1999) p189, J. MoI. Appl. Phys. 79 (1996) p2136. The reported mobility is 0.2 for pentacene, but what was actually applied to the device was demonstrated with a mobility of 10 ⁻² cm ² / Vs. Since tetrachlorobenzene molecules are desorbed from this precursor, it has a high boiling point and is difficult to remove out of the system, and its toxicity is a concern.

  A precursor having a bicyclo structure is described in Advanced Materials, Vol. 11 (1999) p480. In this, a method is disclosed in which ethylene is eliminated from the bicyclo compound and converted to pentacene as shown in the following formula, but it has been pointed out that ethylene is less likely to be eliminated. There is a description that it is insufficient. This is thought to be due to the fact that both ends of the bicyclo ring are condensed with a naphthalene ring, so that the structural change of the conjugated portion during the deethylenation reaction is large and the conversion rate to pentacene is low.

JP-A 61-202467 Japanese Patent No. 2984370 JP-A-11-251601 JP 2000-174277 A Appl. Phys. Lett. Volume 69 (1996) p3086 Science 270 (1995) p972, Optical Materials 12 (1999) p189, J. et al. Appl. Phys. Volume 79 (1996) p2136 Advanced Materials Volume 11 (1999) p480

  As described above, an organic transistor has an effective characteristic that is not found in an inorganic semiconductor. However, an organic transistor that can be manufactured by an easy process and has practical characteristics has not yet been realized. Therefore, a method for manufacturing an organic electronic device using a high-performance and highly stable material by an easy process has been required.

In view of the above, as a result of various studies, by using a bicyclo compound having a specific cyclic structure different from the conventional one as a precursor, it is easy to form a film on a substrate, and the film is heated or the like. By adding an external action, it has been found that the deethylation reaction proceeds efficiently, the purity of the resulting compound is high, and exhibits high characteristics, and the present invention has been achieved. That is, the gist of the present invention, also the following general formula (I) to form a film of the film by applying a solution in a solvent bicyclo compound represented by formula (II) onto a substrate, then from the bicyclo compound converted on the substrate by allowing the ethylene derivative desorbed general formula (Ia) or an organic electronic device using the photovoltaic comprising using as the organic semiconductor compound represented by (IIa), wherein An organic electronic device characterized in that the bicyclo compound represented by the general formula (I) or (II) is a kind of porphyrin compound or phthalocyanine compound represented by the following structural formula, and a method for producing the organic electronic device .

（式（Ｉ）、（ＩＩ）、（Ｉａ）及び（ＩＩａ）中、Ｒ¹〜Ｒ⁸は水素原子又は１価の有機基を表し、Ｒ¹〜Ｒ²は互いに結合して環を形成することはなく、また、Ｑ¹、Ｑ²は２価の有機基、Ｑ³、Ｑ⁴は１価の有機基を表し、Ｒ³とＲ⁵、Ｒ⁴とＲ⁶、Ｑ¹とＱ² 又はＱ³とＱ⁴はそれぞれ結合して環を形成していてもよい）

(In formulas (I), (II), (Ia) and (IIa), R ^{1 to} R ⁸ represent a hydrogen atom or a monovalent organic group, and R ^{1 to} R ² are bonded to each other to form a ring. Q ¹ and Q ² represent a divalent organic group, Q ³ and Q ⁴ represent a monovalent organic group, R ³ and R ⁵ , R ⁴ and R ⁶ , Q ¹ and Q ² or Q ³ and Q ⁴ may be bonded to each other to form a ring)

  The organic electronic device using the photovoltaic power of the present invention is extremely useful because a high-purity and high-performance compound obtained by a simple production method from a specific precursor according to the method of the present invention is used.

Hereinafter, embodiments of the present invention will be described in detail.
(Bicyclo compound)
The bicyclo compound of the present invention, the following general formula having a bicyclo structure (I) or is represented by (II).

上記式（Ｉ）及び（ＩＩ）中、Ｒ¹〜Ｒ⁸は水素原子又は１価の有機基を表し、Ｒ¹〜Ｒ²は互いに結合して環を形成することはないものである。この有機基としては、置換していてもよいアルキル基、アリール基、アルコキシ基、メルカプト基、カルボキシル基、炭素数１０以下のアルコールとのエステル、ハロゲン原子等が挙げられる。中でも望ましいのは、Ｒ³Ｒ⁴Ｃ＝ＣＲ⁵Ｒ⁶の構造のエチレン誘導体が、常圧２００℃で気体あるいは液体、さらに望ましくは常温常圧で気体のものである。また、Ｒ³とＲ⁵又はＲ⁴とＲ⁶は各々互いに環を形成した有機基であってもよい。

In the above formulas (I) and (II), R ^{1 to} R ⁸ represent a hydrogen atom or a monovalent organic group, and R ^{1 to} R ² are not bonded to each other to form a ring. Examples of the organic group include an optionally substituted alkyl group, aryl group, alkoxy group, mercapto group, carboxyl group, ester with an alcohol having 10 or less carbon atoms, and a halogen atom. Among these, an ethylene derivative having a structure of R ³ R ⁴ C═CR ⁵ R ⁶ is preferably a gas or liquid at normal pressure 200 ° C., more preferably a gas at normal temperature and normal pressure. R ³ and R ⁵ or R ⁴ and R ⁶ may each be an organic group that forms a ring with each other.

Q ¹ and Q ² represent a divalent organic group, Q ³ and Q ⁴ represent a monovalent organic group, and Q ¹ and Q ² or Q ³ and Q ⁴ are bonded to each other to form a ring. It may be a group. Examples of the monovalent organic group include a hydrogen atom, a hydroxyl group, an optionally substituted alkyl group having 10 or less carbon atoms, an alkoxy group, a mercapto group, an acyl group, and a carboxyl group and its carbon number of 10 or less. Examples include an ester with alcohol, a formyl group, a carbamoyl group, a halogen atom such as fluorine, chlorine, bromine and iodine, an amino group optionally substituted with an alkyl group having 10 or less carbon atoms, and a nitro group. Further, as an example of an organic group forming a ring in which Q ¹ and Q ² or Q ³ and Q ⁴ are bonded, Q ¹ = CH-CH = Q ² or Q ³ -CH = CH-Q ⁴ is formed. The ring is an aromatic hydrocarbon such as a pyrrole ring, a benzene ring, a naphthalene ring or an anthracene ring, a heterocyclic ring such as a pyridine ring, a quinoline ring, a furan ring or a thiophene ring, a non-aromatic cyclic hydrocarbon such as cyclohexene, and Includes condensed polycyclic compounds such as porphyrin ring and phthalocyanine ring. One or more structures of the above formula (I) or (II) may exist in one molecule of the bicyclo compound of the present invention. First, preferred examples of the bicyclo ring moiety are given. Here, Q ^a and Q ^b represent Q ¹ and Q ² or Q ³ and Q ⁴ in the formulas (I) and (II).

Preferred examples of the bicyclo compound of the present invention will be given. Here, although the bicyclo ring part has illustrated the unsubstituted thing, the thing of the structure which has the substituent shown above can also be used. In the following, molecular structures with good symmetry are mainly exemplified, but asymmetric structures based on combinations of partial structures can also be used. Of course, the compounds of the present invention are not limited to these exemplified compounds. In the figure, M represents a divalent metal. For example, a single metal element such as Cu, Zn, Mg, Ni, Co, Fe, etc., and a trivalent or higher metal and another element are combined to form a divalent metal. Also included are atomic groups such as AlCl, TiO, FeCl, SiCl _{2 and the} like.

(Synthesis method of bicyclo compound)
The bicyclo compound of the present invention can be synthesized using the Diels-Alder reaction. For example, the following synthesis route can be given as an example.

(In the above formula, A1 and A2 represent a leaving group selected from a nitro group, a benzenesulfonic acid group, a halogen atom, a carboxylic acid, and an ester thereof.)
Moreover, it can synthesize | combine directly using Diels-Alder reaction of an acetylene derivative like a following formula.

  While retaining these bicyclo structures, they can be further derivatized to other compounds. Among the above-mentioned bicyclo compounds of the present invention, the porphyrin compound (a) having the structure shown below, in which the bicyclo compound is bonded to the pyrrole ring, changes to a high-performance organic semiconductor benzoporphyrin (b) due to elimination of ethylene. As mentioned. Since this porphyrin compound does not have a planar structure, it has high solubility in a solvent and is difficult to crystallize. Therefore, by applying from a solution, an amorphous or near-amorphous good film is obtained. A tetrabenzoporphyrin film having high planarity can be obtained by subjecting this film to a deethylene reaction by heat treatment. In the case of an unsubstituted, metal-free porphyrin compound, the following chemical reaction proceeds. This reaction proceeds quantitatively by heating to 100 ° C. or higher, preferably 150 ° C. or higher. Further, since the molecule to be desorbed is an ethylene molecule, it hardly remains in the system, and there is no problem in terms of toxicity and safety.

（ａ） （ｂ）

(A) (b)

  Examples of the method for synthesizing this porphyrin compound (bicyclo compound) include the following route.

  The metal complex of the porphyrin compound (bicyclo compound) can be obtained by mixing in an organic solvent that dissolves the porphyrin compound and the metal salt. Any metal salt can be used as long as it dissolves in an organic solvent, and acetate is a typical example. Any solvent may be used as long as it dissolves the metal salt and the bicyclo compound. Preferred examples include chloroform, alcohol, dimethylformamide, tetrahydrofuran, acetonitrile, N-methylpyrrolidone, and a mixed solvent thereof.

(Compounds obtained by elimination of ethylene derivatives from bicyclo compounds)
Bicyclo compounds described above, by an external action such as heating, reaction occurs ethylene derivatives such as the following formula on the substrate is eliminated, the compound having a π conjugated plane structure (Ia) or converted to (IIa) Is done.

The mobility required for application to an electronic device is determined by the magnitude of the current to be controlled, the switching speed, and the element structure. By using the organic semiconductor film formed on the substrate by the method of the present invention, the carrier mobility is 1 × 10 ⁻⁵ cm ² / Vs or more, preferably 1 × 10 ⁻³ cm ² / Vs or more. A device can be provided. The example of the preferable compound formed into a film on the board | substrate below is given. Here, the structure of a metal-free body is illustrated, but a metal salt corresponding to the following examples and a compound further having a substituent can also be used as preferable examples. In addition, molecular structures with good symmetry are mainly exemplified, but an asymmetric structure based on a combination of partial structures can also be used. Of course, the present invention is not limited to these exemplified compounds.

The electronic device of the present invention uses a substance obtained from the bicyclo compound of the present invention as an organic semiconductor, and has two or more electrodes, and a current flowing between the electrodes or a generated voltage is expressed by electricity, light, magnetism, or A device that is controlled by a chemical substance or the like, or a device that generates light, an electric field, or a magnetic field by an applied voltage or current. For example, there are an element that controls current and voltage by applying voltage and current, an element that controls voltage and current by applying a magnetic field, and an element that controls voltage and current by applying a chemical substance. Examples of this control include rectification, switching, amplification, and oscillation. The corresponding devices currently implemented in silicon and the like include resistors, rectifiers (diodes), switching elements (transistors, thyristors), amplifier elements (transistors), memory elements, chemical sensors, etc., or combinations of these elements. Examples include integrated devices. In addition, a solar cell that generates an electromotive force by light, or an optical element such as a photodiode or a phototransistor that generates a photocurrent can be used. Furthermore, the electronic device which does not use the film | membrane obtained using the bicyclo compound of this invention as an organic semiconductor is also mentioned. In this method, the conductivity is controlled by the molecular structure or doping, and it can be used for wiring or used for an insulating layer in a capacitor or FET.

  (1) More specific examples of electronic devices are described in S.A. M.M. Examples include those described in Sze, Physics of Semiconductor Devices, 2nd Edition (Wiley-Interscience 1981).

(2) Field Effect Transistor An example of the organic device of the present invention is preferably a field effect transistor (FET). This is, for example, an element having the structure shown in FIG. Here, 1 is a semiconductor layer, 2 is an insulator layer, 3 and 4 are source and drain electrodes, 5 is a gate electrode, and 6 is a substrate.

Platinum on the electrode, gold, aluminum, chromium, nickel, copper, titanium, magnesium, calcium, barium, other metals such as sodium, InO _2, SnO _2, conductive oxides such as ITO, polyaniline, polypyrrole, polythiophene Conductive polymers such as polyacetylene and acids such as hydrochloric acid, sulfuric acid and sulfonic acid, Lewis acids such as PF ₆ , AsF ₅ and FeCl ₃ , halogen atoms such as iodine, and metal atoms such as sodium and potassium A conductive material such as an additive, carbon black or a conductive composite material in which metal particles are dispersed is used.

Materials used for the insulator layer include polymers such as polymethyl methacrylate, polystyrene, polyvinyl phenol, polyimide, polycarbonate, polyester, polyvinyl alcohol, polyvinyl acetate, polyurethane, polysulfone, epoxy resin, phenol resin, and combinations of these. Polymers, oxides such as silicon dioxide, aluminum oxide and titanium oxide, nitride films such as silicon nitride, ferroelectric oxide films such as SrTiO ₃ and BaTiO ₃ , or the above oxides, nitrides and ferroelectric oxides Examples thereof include a polymer film in which particles such as a product are dispersed. In general, the larger the capacitance of the insulating film, the more advantageous is that the gate voltage can be driven at a lower voltage. This is dealt with by using an insulating material having a large dielectric constant or by reducing the thickness of the insulator layer. Insulator layers are tailored to the material properties such as coating (spin coating and blade coating), vapor deposition, sputtering, printing methods such as screen printing and inkjet, and a method of forming an oxide film on a metal like alumite on aluminum. Can be produced by a method.

(3) SIT
An organic device called an electrostatic induction transistor (SIT) can also be mentioned. In FET, the source and drain electrodes are arranged side by side on the substrate, and the direction of current flow is perpendicular to the electric field induced by the gate, whereas in SIT, the gate is arranged on the grid between the source and drain. , Such that the direction of the current is parallel to the electric field induced by the gate. FIG. 2 shows a schematic diagram thereof. 3 is a source electrode, 4 is a drain electrode, 5 is a gate electrode, and 1 is a semiconductor. In this SIT structure, since the carrier flow spreads on the surface and the distance between the electrodes can be reduced, it is possible to perform high-current and high-speed switching, and for applications that require such operation. Is desirable.

  The gate electrode 5 has a mesh or stripe structure in which carriers pass between the electrodes, and the film thickness is 10 nm to 10 μm, preferably 20 nm to 1 μm. It is desirable that the distance is smaller than the distance between the drains (element thickness). In addition, the gate electrode can use an island-like structure of a thin film of a conductive material such as a conductive polymer. For example, a translucent aluminum electrode having a thickness of 50 nm or less can be used for such applications.

  In order to suppress the entry and exit of carriers from the gate electrode, it is necessary that there is an insulating layer or a barrier between the electrode and the semiconductor. Therefore, a Schottky barrier can be formed by selecting a metal that forms a barrier in the electrode material, for example, aluminum. It is also possible to use patterning of an insulating layer in order to form an insulating film around the electrode.

(4) Diode Another example is a diode element. This is a two-terminal element shown in FIG. 3 having an asymmetric structure. One example is a structure in which a porphyrin material (9) is sandwiched between two metal electrodes (7 and 8) having different work functions. At least one of these needs to form an energy barrier with the porphyrin material. Aluminum is often used as a metal that forms an energy barrier with a p-type semiconductor. However, if the work function is different between the semiconductor and the electrode, an energy barrier is formed. When a voltage is applied to such an element, the flowing current is different when the polarity is reversed, and a rectifying action is observed. Moreover, it is also possible to produce a diode element by bringing the porphyrin material (9) of the present invention into contact with another semiconductor material (10) having a significantly different work function. The electrodes 7 and 8 in this case may be the same or different. Examples of materials to be combined include perylene pigments, phthalocyanine materials, fullerenes, and conjugated polymers. Applications of such diode elements include applications to rectifier elements, photodiodes, and solar cells.

(5) Resistance, etc. A symmetric two-terminal element can also be produced. The resistance between the electrodes can be adjusted to be used as a resistor, or the resistance can be increased to adjust the electric capacity between the electrodes to be used as a capacitor. In addition, it can be applied to a photodetection element such as a photodiode using electrical conduction induced by light irradiation. Such a diode element or resistance element has an advantage that device parameters such as a resistance value can be widely controlled by using the organic semiconductor material exhibiting high mobility of the present invention, which is convenient for integration.

(Device fabrication method)
(1) Substrate treatment The organic device of the present invention is produced on a substrate, and the characteristics can be improved by treating the substrate. This is presumed to be caused by adjusting the hydrophilicity / hydrophobicity of the substrate to improve the quality of the film obtained during film formation, in particular, improving the properties of the interface portion between the substrate and the semiconductor layer. Such substrate treatment includes hydrophobization treatment such as hexamethyldisilazane, cyclohexene, octadecyltrichlorosilane, etc., acid treatment such as hydrochloric acid, sulfuric acid, acetic acid, etc., and alkali treatment such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia, etc. , Ozone treatment, fluorination treatment, plasma treatment with oxygen, argon, etc., Langmuir Blodget film formation treatment, and other insulator or semiconductor thin film formation treatment.

(2) Film thickness In the organic device of the present invention, the compound of the above formula (Ia) and / or formula (IIa) formed on the substrate is used. In the case of the lateral field effect transistor exemplified above, the film thickness when the compound is formed in a film shape does not depend on the film thickness as long as the characteristics of the element are not less than the required film thickness. As the film thickness increases, the leakage current often increases. Accordingly, the preferred film thickness is in the range of 1 nm to 10 μm, but more preferably 10 nm to 500 nm. Further, even when the solution containing the bicyclo compound adheres as droplets instead of being in a uniform film state on the substrate, the thickness of the deposit is preferably within the above range. In addition, it goes without saying that the bicyclo compound of the present invention can be used alone, but it can also be used in a mixture with other compounds, and further can be used in a laminated structure with other layers.

(3) Application | coating The element | device can be produced by melt | dissolving and apply | coating the bicyclo compound of this invention in a solvent. In particular, a molecule in which a molecule converted from a bicyclo compound by a deethylene reaction is hardly soluble in a solvent is useful for forming a film by a coating method. Since the bicyclo structure is three-dimensionally bulky, the crystallinity is poor, and molecules having this structure have good solubility and have the property of being easy to obtain an amorphous film with low crystallinity when applied from a solution. There are many cases. When it changes into a benzene ring by deethylene reaction by heating, it becomes a molecule structure with good crystallinity because it has a molecular structure with good flatness. Therefore, by utilizing the chemical change from the bicyclo compound, an organic semiconductor film having good crystallinity can be obtained by a simple method called a coating method.

  In particular, among the bicyclo compounds of the present invention, those which are converted to a compound having a benzene ring condensed with a pyrrole ring called benzoporphyrin by heat treatment are particularly desirable because they have high properties as an organic semiconductor. As a method of application, casting methods such as dripping a solution, spin coating, dipping, blade coating, wire bar coating, spray coating, etc., and printing methods such as inkjet printing, screen printing, offset printing, letterpress printing, A soft lithography technique such as a microcontact printing method, or a combination of these techniques can be used. Furthermore, as a technique similar to coating, a Langmuir-Blodgett method in which a monomolecular film formed on a water surface is transferred to a substrate and laminated, a liquid crystal in a molten state is sandwiched between two substrates or introduced between substrates by capillary action. A method etc. are also mentioned.

(4) Vapor Deposition The compound of formula (Ia) or (IIa) of the present invention can be formed on a substrate by a vacuum process to produce an organic device. In this case, it is possible to use a vacuum vapor deposition method in which a bicyclo compound is placed in a crucible or a metal boat and heated in a vacuum to adhere to the substrate. At this time, the degree of vacuum is 1 × 10 ⁻³ Torr or less, preferably 1 × 10 ⁻⁵ Torr or less. Various methods can be adopted by adjusting the conditions of the degree of vacuum and the heating temperature of the bicyclo compound as the vapor deposition source. For example, the bicyclo compound can be deposited after first deethylene reaction with a deposition source, or after being deposited as a bicyclo compound at a temperature lower than the reaction temperature, the film formed on the substrate is subjected to heat treatment, It can also be converted into an organic semiconductor film by a deethylene reaction. By adopting such a method of the present invention, it becomes possible to obtain a highly pure compound of formula (Ia) or formula (IIa). Further, since the device characteristics change depending on the substrate temperature, it is necessary to select an optimum substrate temperature, but a range of 0 ° C. to 200 ° C. is preferable. The deposition rate is 0.01 Å / second to 100 Å / second, preferably 0.1 Å / second to 10 Å / second. As a method for evaporating the material, a sputtering method in which ions such as accelerated argon collide can be used in addition to heating.

(5) Heat treatment The deethylene reaction of the bicyclo compound is caused by heat treatment at 100 ° C or higher, preferably 150 ° C or higher. The upper limit is 400 ° C. or lower, preferably 300 ° C. or lower. The higher the temperature, the shorter the reaction time, and the lower the temperature, the longer the reaction time. Depending on the application, the characteristics can be adjusted by partial conversion. In this case, the treatment is performed at a low temperature or in a short time. In addition to heating by heat transfer using a heater, a carbon dioxide laser, an infrared lamp, or light having a wavelength absorbed by the bicyclo compound can be used. At this time, it is possible to heat by providing a layer that absorbs light in the vicinity of the bicyclo compound and absorbing the light in this layer.

(6) Post-treatment of film The produced film can be improved in properties by post-treatment. For example, the heat treatment can relieve distortion in the film generated during film formation, and can improve and stabilize characteristics. Furthermore, a change in characteristics due to oxidation or reduction can be induced by exposure to an oxidizing or reducing gas or liquid such as oxygen or hydrogen. This can be used for the purpose of increasing or decreasing the carrier density in the film, for example.

(7) Doping treatment Further, by adding a trace amount of element, atomic group, molecule, or polymer called doping, the characteristics can be changed to be desirable. For example, doping with an acid such as oxygen, hydrogen, hydrochloric acid, sulfuric acid or sulfonic acid, a Lewis acid such as PF ₆ , AsF ₅ or FeCl ₃ , a halogen atom such as iodine, a metal atom such as sodium or potassium, etc. . This can be achieved by contact with these gases, immersion in a solution, or electrochemical doping treatment. These dopings can be added at the time of synthesizing the material, after the formation of the film, or can be added to the solution in the production process from the solution, or added at the stage of the precursor film. It is also possible to co-deposit materials to be added at the time of vapor deposition, to mix them in the atmosphere at the time of film formation, or to perform doping by accelerating ions in a vacuum and colliding with the film. These doping effects include a change in electrical conductivity due to an increase or decrease in carrier density, a change in carrier polarity (p-type, n-type), a change in Fermi level, etc., which are often used in semiconductor devices. It is what. The doping process can also be used in the organic device of the present invention.

(8) Materials for Substrate, Electrode, Insulating Film, Passivation, etc. As a substrate for the device of the present invention, a polymer plate, film, glass, or metal coated with an insulating film, composite material of polymer and inorganic material Etc. can be used. Electrodes and wiring for electronic device fabrication include metals such as gold, aluminum, copper, chromium, nickel, cobalt, titanium, platinum, conductive polymers such as polyaniline, polypyrrole, polythiophene, polyacetylene, polydiacetylene, and the like. A doped material, a semiconductor such as silicon, germanium, or gallium arsenide and a doped material thereof, a carbon material such as fullerene, carbon nanotube, or graphite can be used. As a method for forming them, a vacuum deposition method, a sputtering method, a coating method, a printing method, a sol-gel method, or the like can be used. The patterning method is also a photolithography method combining photoresist patterning and etching with an etchant or reactive plasma, ink-jet printing, screen printing, offset printing, letterpress printing and other printing methods, micro-contact printing method, etc. The soft lithography technique and a combination of these techniques can be used. In addition, it is also possible to directly produce a pattern by irradiating an energy beam such as a laser or an electron beam to remove the material or changing the conductivity of the material.

  In the electronic device of the present invention, a protective film can be formed to minimize the influence of outside air. Examples thereof include polymer films such as epoxy resin, acrylic resin, polyurethane, polyimide, and polyvinyl alcohol, inorganic oxide films such as silicon oxide, silicon nitride, and aluminum oxide, and nitride films. Examples of the polymer film include a method of applying and drying a solution, and a method of polymerizing by applying or vapor-depositing a monomer. Further, a crosslinking treatment or a multilayer film can be formed. For the formation of the inorganic film, a formation method using a vacuum process such as a sputtering method or a vapor deposition method, or a formation method using a solution process typified by a sol-gel method can be used.

(Device application fields)
(1) Active matrix The organic device of the present invention can be used as a switching element of an active matrix of a display. This utilizes the fact that the current between the source and drain can be switched by the voltage applied to the gate, so that the switch is turned on only when a voltage is applied to or supplied to a certain display element, and the circuit is disconnected at other times. By doing so, a high-speed, high-contrast display is performed.

  Examples of the display element to be applied include a liquid crystal display element, a polymer dispersed liquid crystal display element, an electrophoretic display element, an electroluminescent element, and an electrochromic element. In particular, the organic electronic device of the present invention is advantageous in that an element can be manufactured by a low-temperature process, and a substrate that cannot withstand high-temperature processing such as a plastic substrate, a plastic film, or paper can be used. In addition, since the device can be manufactured by a coating or printing process, it is suitable for application to a large area display. Further, as an alternative to the conventional active matrix, it is advantageous as an element capable of an energy saving process and a low cost process.

(2) IC
Further, by integrating transistors, a digital element or an analog element can be realized. Examples of these include logic circuits such as AND, OR, NAND, NOT, memory elements, oscillation elements, amplification elements, and the like. Furthermore, an IC card or an IC tag can be produced by combining these.

(3) Sensors Organic semiconductors undergo significant changes in characteristics due to external stimuli such as gases, chemicals, and temperatures, so their application to sensors is also conceivable. For example, by measuring the amount by which the characteristics of the organic device of the present invention change due to contact with a gas or liquid, it is possible to qualitatively or quantitatively detect chemical substances contained therein.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

(1) Synthesis example 1
The bicyclo compound (1) was synthesized by the following synthesis route.

  53.5 ml of thiophenol and 51.25 g of potassium hydroxide were dissolved in 600 ml of ethanol. To this solution, 19.4 ml of cis-1,2-dichloroethylene was slowly added dropwise. Thereafter, the mixture was stirred at room temperature for 30 minutes, and further heated and stirred at 80 to 90 ° C. for 23 hours. The solution was concentrated under reduced pressure, water was added thereto, and the mixture was extracted with chloroform. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain cis-1,2-phenylthioethylene.

  This cis-1,2-phenylthioethylene and 750 mg of diphenyl diselenide were dissolved in 100 ml of methylene chloride. The solution was cooled in an ice bath and 175 ml of 30% aqueous hydrogen peroxide was slowly added. The crystals precipitated by vigorous stirring overnight at room temperature were filtered off, dissolved in chloroform, washed with water, saturated aqueous sodium hydrogen carbonate, and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Further, this was dissolved in 500 ml of chloroform, and 84 g of m-chloroperbenzoic acid was slowly added while cooling in an ice bath and stirred overnight at room temperature. The precipitated solid was filtered through Celite, and the organic layer was washed with water, saturated aqueous sodium hydrogen carbonate and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. This solid was rinsed with ether to obtain 67.06 g of cis-1,2-diphenylsulfonylethylene (yield 87%). Colorless crystals, mp 100-101 ° C.

  This cis isomer and a catalytic amount of iodine were dissolved in methylene chloride, and those that precipitated as a solid by irradiation with sunlight were filtered to obtain trans-1,2-diphenylsulfonylethylene. Colorless crystals, mp 219.5 ° C. By dissolving 29.33 g of trans-1,2-diphenylsulfonylethylene in 200 ml of toluene and then adding 11.4 ml of 1,3-cyclohexadiene, followed by dry distillation for 21 hours and then recrystallization, 5,6-diphenylsulfonyl 35.66 g (yield 96.5%) of -bicyclo- [2,2,2] oct-2-ene were obtained.

  7.76 g of this was placed in a reaction vessel, purged with nitrogen, and 50 ml of anhydrous tetrahydrofuran (THF) was added and dissolved. Thereto was added 2.43 ml of ethyl isocyanoacetate, the reaction solution was cooled in an ice bath, and 50 ml of a 1M solution of t-BuOK / THF was slowly added dropwise. Thereafter, the reaction solution was returned to room temperature and stirred overnight. Quenched with 1N hydrochloric acid, extracted with chloroform, washed with water and saturated brine, dried over anhydrous sodium sulfate, concentrated under reduced pressure, and purified by silica gel chromatography to obtain 4,7-dihydro-4. , 7-ethano-2H-isoindole-1-carboxylate 3.49 g (yield 80.4%). Colorless crystals, mp 129-130 ° C.

A solution obtained by dissolving 0.109 g of the obtained crystals in 15 ml of THF was added dropwise with stirring at 0.144 g of LiAlH ₄ at 0 ° C., and the mixture was stirred at 0 ° C. for 2 hours. The reaction solution was poured into 25 mL of saturated water and extracted three times with 50 mL of chloroform. To the combined extracts, 0.010 g of p-toluenesulfonic acid was added and stirred at room temperature for 12 hours. After adding 0.150 g of p-chloranil and stirring at room temperature for 12 hours, the reaction solution was poured into water. The organic phase was separated, washed 5 times with 250 mL of aqueous sodium bicarbonate, once with 250 mL of water, and 100 mL of saturated brine, and then dried over magnesium sulfate. The residue obtained by distilling off the solvent was purified by column chromatography (chloroform, alumina) to obtain 0.094 g of a porphyrin compound (1) containing the target bicyclo structure.

A main peak of m / Z = 622 (M ⁻ ) was observed in the negative ion mode of the MALDI-TOF mass spectrum. The thermal analysis result (DTA-TG) of this compound is shown in FIG. Weight loss and exotherm are seen in the temperature range of 146 ° C to 198 ° C. This weight loss (about 18%) corresponds to the elimination of four ethylene molecules from the bicyclo compound and conversion to tetrabenzoporphyrin.

  FIG. 5 shows an IR spectrum of a film obtained by dropping a chloroform solution of the porphyrin compound (1) on the gold vapor-deposited film and drying the solvent. FIG. 6 shows the IR spectrum of the film heated at 210 ° C. for 2 minutes. A change in the IR spectrum reflecting the change in the molecular structure accompanying the elimination of the ethylene molecule is observed, and it can be seen that tetrabenzoporphyrin is generated by heating the film.

A mass obtained by heating the bicyclo compound (1) at 210 ° C. for 10 minutes was measured by the MALDI-TOF method in the negative ion mode similarly to the bicyclo compound. Then, a molecular ion peak of tetrabenzoporphyrin of m / Z = 510 (M ⁻ ) was observed, and conversion to tetrabenzoporphyrin by heating was confirmed. Further, since the IR spectrum of the heated product almost coincided with the IR spectrum after heating measured on the substrate, it was confirmed that what was purified by heating was tetrabenzoporphyrin. FIG. 7 shows a comparison of UV-visible absorption spectra of a film obtained by spin-coating a chloroform solution of the bicyclo compound (1) on a quartz glass substrate and drying the solvent, and a film obtained by heating the film at 210 ° C. for 10 minutes. Shown in It is observed that a change from a bicyclo compound to tetrabenzoporphyrin (690 nm) is observed as an increase in Q band intensity and a long wavelength shift in the porphyrin absorption spectrum.

(2) Synthesis example 2
0.02 g of the bicyclo compound (1) of Synthesis Example 1 and 0.1 g of zinc acetate dihydrate were stirred in a mixed solvent of 30 mL of chloroform and 3 mL of methanol for 3 hours at room temperature. The reaction solution was washed twice with 100 mL of water and once with 40 mL of saturated brine, and the organic phase was dried over sodium sulfate. The solid obtained by concentrating the solvent was recrystallized with a mixed solvent of chloroform / methanol to obtain 0.022 g of a zinc complex of the bicyclo compound (1). Furthermore, only a single peak was fractionated and purified by gel permeation chromatography (Nippon Analytical Industry JAIGEL-1H, 2H, chloroform). Mass spectra were measured and molecular peaks were confirmed.

(3) Example 1
A gap of length (L) 10 μm and width (W) 250 μm is formed by photolithography on an N-type silicon substrate (Sb-doped, resistivity 0.02 Ωcm or less, manufactured by Sumitomo Metal Industries, Ltd.) on which a 300 nm oxide film is formed. Gold electrodes (source and drain electrodes) were formed. In addition, an oxide film at a position different from this electrode is etched with a hydrofluoric acid / ammonium fluoride solution, gold is deposited on the exposed Si portion, and an electrode for applying a voltage to the silicon substrate (gate electrode) It was.

  Dissolving 2 mg of the bicyclo compound (1) obtained in Synthesis Example 1 in 1 mL of chloroform and evaporating the solvent between the source and drain electrodes was repeated several times to obtain a good film. When X-ray diffraction of this film was observed, no sharp peak was observed. When the film was observed under a crossed Nicol microscope, an image with a dark surface was obtained, and the film was isotropic. Therefore, it can be seen that the obtained film is amorphous.

The substrate was heated at 210 ° C. for 10 minutes. When X-ray diffraction of the obtained film was observed, a sharp peak was observed. In addition, when the film was observed under a crossed Nicol microscope, a colored domain structure was observed. Therefore, it can be seen that the obtained film is crystalline. This is because the bicyclo compound changed to tetrabenzoporphyrin and became crystalline. Further, the obtained film had low solubility in a solvent and was hardly soluble in an organic solvent. The characteristics of the field effect transistor thus obtained were measured using a semiconductor parameter analyzer 4155C manufactured by Agilent Technologies. The measurement results are shown in FIG. From this figure, the effective mobility was calculated to be 1 × 10 ⁻³ cm ² / Vs.

(4) Example 2
Using chlorobenzene as a solvent, a bicyclo compound film was prepared in the same manner as in Example 1, and converted to benzoporphyrin by heating. The characteristics of the field effect transistor thus obtained were measured using a semiconductor parameter analyzer 4155C manufactured by Agilent Technologies. The effective mobility was calculated to be 1.6 × 10 ⁻² cm ² / Vs.

(5) Example 3
A solution obtained by dissolving oxydianiline and benzophenonetetracarboxylic anhydride in dimethylformamide at a molar ratio of 1: 1 is spin-coated on a slide glass on which aluminum is vapor-deposited, and heated at 250 ° C. to form a 500 nm polyimide film. Produced. A bicyclo compound film was produced on this film in the same manner as in Example 1, and converted into benzoporphyrin by heating.

On top of this, gold was vapor-deposited through a shadow mask prepared using a tungsten wire with a diameter of 25 μm as a gap portion, and source and drain electrodes having a gap with a width (W) of 250 μm and a length (L) of 25 μm were prepared. The characteristics of the field effect transistor thus obtained were measured using a semiconductor parameter analyzer 4155C manufactured by Agilent Technologies. The effective mobility was calculated to be 3.7 × 10 ⁻² cm ² / Vs.

(6) Example 4
Using the zinc complex synthesized in Synthesis Example 2, an FET was produced in the same manner as in Example 1. When this FET characteristic was measured, the effective mobility was 1.9 × 10 ⁻⁴ cm ² / Vs.
In the above Examples 1 to 4, the value of effective mobility was stable.

(7) Example 5: Preparation and evaluation of diode and optical element This compound was spin-coated on a gold electrode to form a film of 500 mm. On top of that, the following perylene compound was laminated by 1000-mm vapor deposition. A semitransparent aluminum electrode was further formed thereon by vapor deposition to form a sandwich structure.

  Depending on the direction of the voltage applied to the gold electrode and the aluminum electrode, this device operates as a rectifying device when a positive voltage is applied to the gold electrode and one more current flows than when a negative voltage is applied. It was. When this element was irradiated with light from the aluminum side, a 1 V photovoltaic power was observed.

The schematic diagram of the field effect transistor (FET) of this invention is shown. The schematic diagram of the electrostatic induction transistor (SIT) of this invention is shown. The schematic diagram of the diode element of this invention is shown. It is a figure which shows the thermal-analysis result of the porphyrin compound obtained by the synthesis example 1. It is a figure which shows IR spectrum of the film | membrane which dried the solution of the porphyrin compound (1) obtained by the synthesis example 1. FIG. 6 is a diagram showing an IR spectrum of a film obtained by further heating the film of FIG. 5 obtained in Synthesis Example 1. FIG. It is a figure which shows the thin film absorption spectrum before and behind the heating in the synthesis example 1. FIG. It is a figure which shows the result of having observed the FET characteristic in Example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor layer 2 Insulator layer 3 Source 4 Drain electrode 5 Gate electrode 6 Substrate 7, 8 Metal electrode 9 Porphyrin material 10 Other semiconductor materials

Claims (8)

Following general formula (I) or to form a film of the film by applying a solution in a solvent bicyclo compound represented by formula (II) onto a substrate, followed by desorbing the ethylene derivative from the bicyclo compound also the substrate on the converted general formula (Ia) is an organic electronic device that uses a photovoltaic comprising using a compound represented by the organic semiconductor in (IIa), the general formula (I) or (II ) Is a kind of a porphyrin compound or a phthalocyanine compound represented by the following structural formula.

(In formulas (I), (II), (Ia) and (IIa), R ^{1 to} R ⁸ represent a hydrogen atom or a monovalent organic group, and R ^{1 to} R ² are bonded to each other to form a ring. Q ¹ and Q ² represent a divalent organic group, Q ³ and Q ⁴ represent a monovalent organic group, R ³ and R ⁵ , R ⁴ and R ⁶ , Q ¹ and Q ² or Q ³ and Q ⁴ may be bonded to each other to form a ring)

The organic electronic device according to claim 1, wherein the carrier mobility is 1 × 10 ⁻⁵ cm ² / Vs or more. A general formula (I) or a bicyclo compound porphyrin compound represented by (II), and also the general formula (Ia) is a compound represented by (IIa), a kind of the compound represented by the following structural formula the organic electronic device according to claim 1 or 2, characterized in that.

Following general formula (I) or to form a film a film by coating a solution dissolved in a solvent bicyclo compound represented by formula (II) onto a substrate, then to desorb ethylene derivative from the bicyclo compound by, the following general formula (Ia) or on the substrate encounters method for manufacturing an organic electronic device that utilizes photovoltaic described the step of converting the compound represented including請 Motomeko 1 (IIa) A method for producing an organic electronic device , wherein the bicyclo compound represented by the general formula (I) or (II) is a kind of a porphyrin compound or a phthalocyanine compound represented by the following structural formula .

(In formulas (I), (II), (Ia) and (IIa), R ^{1 to} R ⁸ represent a hydrogen atom or a monovalent organic group, and R ^{1 to} R ² are bonded to each other to form a ring. Q ¹ and Q ² represent a divalent organic group, Q ³ and Q ⁴ represent a monovalent organic group, R ³ and R ⁵ , R ⁴ and R ⁶ , Q ¹ and Q ² or Q ³ and Q ⁴ may be bonded to each other to form a ring)

A film in which a solution in which a bicyclo compound is dissolved in a solvent is applied on a substrate to form a film, and then the film is subjected to heat treatment to desorb an ethylene derivative from the bicyclo compound. Ia) or a method for manufacturing the organic electronic device according to claim 4 which is converted to a compound represented by (IIa). A general formula (I) or a bicyclo compound porphyrin compound represented by (II), and also the general formula (Ia) is a compound represented by (IIa), a kind of the compound represented by the following structural formula A method for producing an organic electronic device according to claim 4 or 5 .

A film is formed by applying a solution in which a bicyclo compound represented by the following structural formula (a) is dissolved in a solvent on a substrate, and then the film is subjected to heat treatment, whereby the bicyclo compound is converted to ethylene on the substrate. A method for producing an organic electronic device using photovoltaic power, comprising the step of desorbing and converting to a compound represented by the following structural formula (b):

An organic semiconductor device using photovoltaic power, produced by the method according to claim 4 .

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