KR20070019582A - Polymerizable dielectric material - Google Patents

Abstract

The present invention provides novel polymeric dielectric materials comprising crosslinkable organic amine derivatives and crosslinked polymers obtained therefrom, novel methods of preparing dielectric layers for electronic products, useful for preparing dielectric layers for electronic products, and It relates to an electronic product obtained by the above method.

Description

Polymerizable Dielectric Material {POLYMERIZABLE DIELECTRIC MATERIAL}

1 illustrates the manufacture of a transistor device.

2 illustrates a transistor device including a dielectric layer in accordance with the present invention.

3 shows the threshold characteristics of a transistor device according to the invention and a transistor device according to the prior art.

The present invention relates to novel polymeric dielectric materials comprising crosslinkable organic amine derivatives and crosslinked polymers obtained therefrom, which are useful for the preparation of dielectric layers of electronic products. The present invention also relates to a novel method for producing a dielectric layer of an electronic product, and to an electronic product obtained by the method.

A promising approach for large scale, low cost fabrication of organic substrate integrated circuits is to perform the fabrication steps by solution processing. This allows for roll-to-roll processing possibilities that can coat large areas and print at high speeds. An important requirement of an insulator suitable for this technique is sufficient solubility in a suitable process solvent such that the solution wets the surface and coats and the formed film is tightly adhered. This requires optimization of the solution rheology and evaporation rate. In addition, in the case of a multilayer structure, it is essential that the solvent used for the deposition of each layer does not dissolve or swell the layer in contact with the layer, and thus prevent poor interface and interlayer diffusion. When applying each layer through solution, a solvent with solubility parameters inadequate for the preceding layer is required, which is sometimes referred to as an orthogonal solvent. The solvent parameter range can be significantly expanded if the preceding layer can carry out chemical processes such as crosslinking. By crosslinking the film in situ, shorter potentially mobile molecular units are bound into the fixed network.

In a typical device structure, the insulator is applied on the semiconductor surface. Most semiconductors contain aliphatic chains, which give solubility and often improve form. However, the effect of the chemical structure is to thermodynamically drive the aliphatic groups to the semiconductor surface, making the surface hydrophobic and having very low energy. This wets the surface during solution application of the insulator, which is an important consideration.

The operating device exhibits high dielectric resistance, has an optimal dielectric constant as defined by the geometry of the device, and requires an insulator that is chemically inert for the life of the device. High electron band spacing organic materials provide excellent electrical insulation, while the dielectric constant of the film is a function of electron polarization and is often dependent. The electron polarization can be increased by the addition of polar groups.

EP 1 416 004 A1 (the content of which is incorporated herein by reference in its entirety) discloses a formulation comprising a crosslinkable organic amine derivative, optionally a multifunctional compound capable of reacting with said amine, and a polymerization initiator. . EP 1 416 004 A1 also discloses corresponding crosslinked polymer products, for example melamine resins, and their use for the preparation of dielectric layers of electronic devices.

However, while the crosslinkable insulators work well for some multilayer devices, there are still problems with the operational hysteresis phenomena that sometimes appear in this type of device. This hysteresis and some other related problems are believed to stem from mobile ions inside the semiconductor or insulator layer. One way to overcome these problems is obviously to purify the materials. However, purification of the insulator produces a change in its underlying properties, especially when a polymerization catalyst or initiator necessary for crosslinking of the insulator is present in the purification of the polymer.

It is an object of the present invention to provide an improved method of making a material and dielectric layer that does not have the disadvantages of conventional dielectric materials and manufacturing methods. A further object of the present invention is to provide a formulation comprising a crosslinkable amine derivative which is particularly suitable for the preparation of the dielectric layer of a dielectric device. It is a further object of the present invention to provide an improved method for producing a dielectric layer of an electronic device which is particularly suitable for the production of large numbers of pieces and / or large areas. Further objects of the invention relate to organic electronic devices. Other objects of the present invention are immediately apparent to those skilled in the art from the following detailed description.

The inventors of the present invention have found that the above objects can be achieved by using the materials and methods claimed in the present invention. Accordingly, the inventors have found that in crosslinkable dielectric formulations for use as insulating layers in electronic devices as disclosed in the prior art, the incorporation of a polymerization catalyst, for example an acidic reagent, can be a source of mobile ionic impurities, It has been found to cause undesirable hysteresis in electronic devices. The inventors have also found that these problems can be overcome by using polymeric or polymer bonded thermal acid as the polymerization initiator. The polymer bonded thermal acid has a high molecular weight and therefore cannot be mobile in the insulator and, once reacted, does not significantly alter the properties of the insulator or device. An additional advantage of using thermal acid is that it can lower the temperature at which crosslinking occurs.

In addition to the dielectric layers for electronic devices, the materials and methods according to the invention can also be used in other polymer products or applications. For example, it can be used for manufacture of the optical polymer film for liquid crystal display films in which free radical polymerization is disadvantageous. In such cases, cationic polymerization can be used without increasing the conductivity of the LC film.

Definition of Terms

The term electronic device includes all devices and components used in electronics, preferably microelectronics, including electro-optical functionality, such as resistors, diodes, transistors, integrated circuits, light emitting diodes and all-optical displays. Include. In particular, the term electronic device includes organic electronic devices, ie all electronic devices and components in which one or more functionalities, such as conductivity, semiconductivity and / or luminescence, are realized by polymers and / or organic materials. Examples of such organic electronic devices include organic light emitting diodes (OLEDs), organic field effect transistors (OFETs), and devices containing a plurality of such components, such as polymer integrated circuits containing OFETs, and examples. For example, it is an active matrix that includes a liquid crystal display (LCD) and a thin film transistor (TFT) of other displays.

The term dielectric layer or material refers to a layer or material that exhibits very low or even nonconductive electrical properties, particularly with a resistance of at least 10 ⁺⁸ Ωcm.

The term layer as used in this application includes self-supported, ie free-standing films as well as coating layers on or between supporting substrates, which exhibit somewhat significant mechanical stability and flexibility. The layer may be flat or have any three dimensional variable shape, including patterning.

The term substrate as used in this application relates to the portion of the organic device on which the amine mixture is coated.

The term substrate is also used as starting material used as the base of the device. The material is typically a silicon wafer, glass or plastic (eg PET foil). In a typical transistor device, the source and drain electrodes will already have a structured surface (lithography, thermal evaporation or printing method). On top of the structure, a surface energy modification layer or arrangement layer is optionally deposited, followed by a semiconductor (for example polyhexylthiophene), an insulator, ie an amine mixture and finally a gate electrode.

Summary of the Invention

The present invention

At least one crosslinkable organic amine derivative capable of forming a polymer crosslinked by itself and / or with each other and / or with at least one further multifunctional compound in a polymerization or crosslinking reaction,

At least one polymeric or polymer bound initiator capable of initiating the polymerization or crosslinking reaction.

It relates to a formulation comprising a.

The present invention also relates to crosslinked polymer products obtainable by crosslinking the above formulations.

The invention also relates to the use of such formulations and crosslinked polymers as dielectric or insulating materials in electronic and electro-optical devices.

The invention also relates to a method of making a dielectric layer of an electronic device using the agent or polymer.

The invention also relates to a dielectric layer obtainable by the above method, and to an electronic, optical or electro-optical device comprising the dielectric layer.

Preferred electronic, optical or electro-optical components or devices include, but are not limited to, organic field effect transistors (OFETs), thin film transistors (TFTs), components of integrated circuits (ICs), radio frequency identification (RFID) tags, and organic light emitting diodes (OLEDs). ), Electroluminescent displays, flat panel displays, backlights, photodetectors, sensors, logic circuits, memory elements, capacitors, photovoltaic (PV) cells, charge injection layers, Schottky diodes, planarization layers, antistatic films, conductive substrates or patterns , Photoconductors, and electrophotographic devices.

When using a crosslinkable formulation according to the invention comprising a polymeric or polymer bonded thermal acid having a high molecular weight as a polymerization initiator, the initiator will not migrate in the final crosslinked polymeric material. Thus, after polymerization, the initiator does not significantly alter the properties of the polymeric material or insulator layer or the device comprising the same.

Especially

From 50 to 99.5% by weight of component A,

From 0 to 50% by weight, preferably 0.5 to 50% by weight of component B, and

0-10% by weight of component C

Formulations comprising are preferred, wherein

A preferably comprises at least one organic amine derivative as disclosed above and below, comprising at least two identical or different groups of formula 1 as defined above,

B comprises one or more multifunctional compounds, which can react with one or more compounds of component A to form a crosslinked polymer,

C comprises at least one initiator as disclosed above and below for the polymerization of component A or components A and B.

Another object of the present invention is a crosslinked polymeric material obtainable by polymerization of a formulation as disclosed above and below.

Another object of the present invention

a) manufacturing a substrate optionally comprising one or more layers or patterns of a material having insulation, inversion, conduction, electrons and / or photon functionality,

b) forming a thin layer of a formulation comprising at least one crosslinkable organic amine derivative as defined above and below on the substrate or on a defined region of the substrate, and

c) initiating the polymerization of said formulation.

It includes a method of manufacturing a dielectric layer of the electronic device.

A further object of the invention relates to an electronic device obtainable by the method according to the invention.

The object of the invention also relates to an electronic device comprising as a dielectric a crosslinked polymeric material according to the invention.

Suitable crosslinkable organic amines for component A are disclosed in EP 1 416 004 A1. Particular preference is given to amine derivatives comprising at least two identical or different groups of the general formula (1):

Where

R ^a is H,-[(CR'R ") _v -CO] _r -R"',-[(CR'R") _v -O-] _r -R"'or-(CR'R") _v -NHZ,

R ′, R ″, R ″ ′ independently of one another are H, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, which may be substituted by halogen,

Z is H or a protecting group,

v is 0 or 1 or more,

r is 1 or more, but if v is 0, r is 1.

Amine derivatives comprising groups of formula (1) exhibit favorable solution properties for fluidity and intercoating adhesion and are therefore particularly suitable for the preparation of dielectric layers of electronic devices. This finding also applies to crosslinked polymer products obtainable by crosslinking the amine derivatives on their own or with one or more multifunctional compounds. Such derivatives can also effectively wet low energy hydrophobic surfaces, especially the surfaces of organic semiconducting materials. In addition, advantageous changes in the electrical, viscoelastic behavior and densification, ie improved flexibility, elasticity, durability, solvent resistance and by self-crosslinking or crosslinking the amine derivatives according to the invention with one or more multifunctional compounds, It has been observed that / or insulator properties can be achieved.

The amine derivatives according to the invention have functional groups which are capable of carrying out chemical reactions on their own or with co-components, in particular multifunctional compounds as defined below, to form crosslinked polymer networks. The chemical reaction is controllable in that the amine derivative can be stored at room temperature, i.e. above 20 ° C or below, essentially without the occurrence of a chemical reaction. The chemical reaction can be initiated, for example, by raising the temperature, changing the pH, or irradiating with electromagnetic or particle irradiation, or reactive compounds. Preference is given to amine derivatives which, by themselves or crosslinked with one or more multifunctional compounds, produce stable dielectric films having high resistance, in particular 10 ^{+ 8} Ωcm or more.

Preferably, the amine derivatives according to the invention are as defined above wherein at least one of the R ^a groups comprises an alkyl group of 1 to 12 carbon atoms or an alkenyl group of 2 to 12 carbon atoms and these groups may be substituted by halogen. Two or more groups of the same formula (I).

The amine derivatives according to the invention also preferably comprise at least one —OH group. Most preferably, as defined above, at least one of the R ^a groups is-[(CR'R ") _v -O-] _r -H and R ', R", v and r as defined above. Two or more groups of the same formula (I).

According to a preferred embodiment of the present invention, the amine derivative is selected from the group of formulas 1a to 1c:

In the above formulas,

R ¹ , R ² , R ³ are independently of each other a group of formula (2):

R ^a , R ^b , R ^c , and R ^d are each independently of H,-[(CR'R ") _v -CO] _r -R"',-[(CR'R") _v -O-] _r- R "'or-(CR'R") _v -NHZ,

R ′, R ″, R ″ ′ are independently of each other H, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, and these groups may be substituted by halogen,

Z is H or a protecting group,

v is 0 or 1 or more,

r is 1 or more, if v is 0, r is 1,

W is O or S,

R ³ in addition to the above meanings may be alkyl, cycloalkyl, aryl or alkylaryl groups, which groups are optionally substituted by halogen.

In the following, groups, substituents and indices R ¹ , R ² , R ³ , R ^a , R ^b , R ^c , R ^d , R ', R ", R"', Z, v, r and n are not indicated otherwise Has the meaning given above.

It is emphasized that each group, substituent and index of two or more appearing in one of the above or below formulas may have the same or different meanings.

By the choice of substituents R ^a and R ^b , the physical and chemical properties of the amine derivatives, their polymerizable mixtures and the resulting polymers can be influenced to meet the requirements for the preparation of the dielectric layer of the organic electronic device. In addition, the processing of the synthetic mixtures containing such amine derivatives and their polymerization properties are influenced by the substituents R ^a and R ^b .

At least one of groups R ¹ , R ² , R ³ and / or groups R ^a , R ^b , R ^c , R ^d comprises an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms, these groups Preference is given to amine derivatives selected from the group of the formulas 1a to 1c which may be substituted by this halogen.

Z is a protecting group of H or amino functional groups, for example formyl, tosyl, acetyl, trifluoroacetyl, methoxy, ethoxy, tert-butoxy, cyclopentyloxy as well as phenoxycarbonyl, carbenzyloxy and p-nitrobenzyloxy.

The index v is preferably 1 to 6, most preferably 1 or 2.

The index r is preferably 1 to 4, most preferably 1 or 2.

Preferred are derivatives selected from the group of formulas 1a and 1b, in which one, two or three of the groups R ¹ , R ² , R ³ are the groups of formula 2a:

Where

R ^a , R ', R ", R"', v and r have the meanings given above.

According to a preferred embodiment of formula 2a, the following variables themselves or combinations of two or more of these variables are preferred:

Two or three of the groups R ¹ , R ² , R ³ of formulas 1a and 1b independently of one another have the meaning according to formula 2a.

R ″ 'is an alkyl group having 2 to 12 carbon atoms, preferably 3 to 12 carbon atoms, which may be substituted by halogen.

R ″ 'is an alkyl group having 2 to 8 carbon atoms, preferably 3 to 8 carbon atoms, most preferably 3, 4, 5 or 6 carbon atoms, wherein one, more or all H atoms are halogen, preferably F Or substituted by Cl.

r is 1 or 2, preferably 1.

v is 1, 2, 3 or 4, preferably 1.

R 'and R "are H.

R ^a is H or comprises at least one —OH group.

R ^a is-[(CR'R ") _v -O-] _r -H, wherein R ', R", v and r are as defined above, preferably R' and R "are H, v is preferably 1, 2, 3 or 4, most preferably 1 or 2, r is preferably 1 or 2 and most preferably 1.

R ^a is —CH ₂ —OH.

Also preferred are derivatives selected from the group of formulas 1a and 1b, in which one, two or three of the groups R ¹ , R ² , R ³ are independently of each other a group of formula 2b:

Where

v1 is 0, 1, 2, 3 or 4, preferably 1,

v2 is 1, 2, 3 or 4, preferably 1,

R ″ 'is preferably H, or an alkyl group having 1 to 12, preferably 2 to 8 carbon atoms, wherein one, more or all H atoms may be substituted by halogen, preferably F or Cl have.

In addition to the above preferred conditions, one or more of the groups R ¹ , R ² , R ³ and / or groups R ^a , R ^b , R ^c , R ^d may be substituted by halogen or an alkyl group having 1 to 12 carbon atoms or carbon atoms An alkenyl group of 2 to 12,

When at least one of R ^a , R ^b is H, fast curing reaction and good film hardness are achieved;

When at least one of R ^a , R ^b is —OH or —CH ₂ OH, the mixture comprising said amine derivatives exhibits favorable flowability properties;

A more flexible dielectric layer can be obtained when at least one of R ^a , R ^b is — (CH ₂ ) _v —OR ″ ′ where _v ≧ 1 and R ″ ′ is an alkyl group having at least 2 carbon atoms, ;

A polymerizable comprising an amine derivative of the invention when at least one of R ^a , R ^b is — (CH ₂ ) _v —OR ″ ′, where _v ≧ 1 and R ″ ′ is an alkyl group having at least 2 carbon atoms It has been found that the relatively low viscosity, improved flowability, flatness and wettability of the mixture and good interfilm adhesion can be obtained, and the mixture also exhibits high formulation stability and the resulting dielectric layer has good flexibility.

The amine derivatives according to the invention may also have —CO— groups in addition to NH, N—CH ₂ —OH and / or N—CH ₂ —O-alkyl functional groups.

In a preferred embodiment of the invention, the formulation comprises two or more crosslinkable organic amine derivatives.

Particular preference is given to amine derivatives which show not only one kind of substituent but also a combination of different substituents, in particular those mentioned above and / or combinations of two or more amine derivatives according to the invention, because they are dielectric layers of organic electronic devices. This is because it satisfactorily satisfies the processing technique requirements for the production of and the dielectric layer itself.

Using the preparations according to the invention, even hydrophobic surfaces, in particular surfaces with surface energy of less than 20 mN / cm, can be wetted and coated to produce an adhesive film, which can be cured. Thus, a pattern or layer of materials with low surface energy and very low surface energy, such as a semiconducting polymer with aliphatic chains, for example for improved solubility, can be coated with the material of the invention.

Amine derivatives according to formulas 1a and / or 1b, wherein the amine derivatives disclosed above, in particular one, two or three of substituents R ¹ , R ² , R ³ , are independently of each other formulas (2), in particular of formulas (2a) and / or (2b) Or a combination of two, three or more amine derivatives is preferred as component A.

In a preferred embodiment, melamine-formaldehyde resin and urea-formaldehyde resin are used as component A. Commercially available melamine-formaldehyde resins using, for example, the trade name Cymel® are commercially available from CYTEC INDUSTRIES INC., West Paterson, NJ 07424, USA. You can get it. A commercially available urea-formaldehyde resin is UI20-E (CYTEC INDUSTRIES INC.).

In another preferred embodiment of the invention, the formulation comprises one or more additional multifunctional compounds (component B), which compounds can react with one or more components of A to form a crosslinked polymer. The multifunctional compound is advantageously chosen such that the resulting mixture exhibits good flowability for the technique used to prepare the thin dielectric layer. In addition, the mechanical and electrical properties of the resulting dielectric layer can be influenced by the selection of the multifunctional compound. In addition, the water absorption of the resulting amine polymer can be minimized by using a multifunctional compound having at least one hydrophobic group, for example an aliphatic alkyl chain.

Preferably the at least one multifunctional compound of component B is an organic compound having at least two functional groups from the group consisting of —OH, —NH ₂ , —COOH and reactive derivatives thereof, and reacts with at least one component of A to crosslink The bound polymer can be formed. Preferred multifunctional compounds are aliphatic, cycloaliphatic and aromatic diols, polyols, diacids, polyacids, diamines, polyamines and reactive derivatives thereof. Reactive derivatives are advantageously such derivatives in which the desired functional groups can be released under suitable reaction conditions, for example by removal of a protecting group. Preferred groups of multifunctional compounds are alkanediols, polyhydroxyalkyl (meth) acrylates, poly (meth) acrylic acids, polyols and optionally substituted phenol formaldehyde condensation copolymers having 2 to 12 carbon atoms. Examples of such compounds include 1,4-butanediol, polyhydroxyethyl methacrylate, polyacrylic acid, polyurethane polyols, polyethylene imines, polyvinyl phenols, as well as cresol formaldehyde condensation copolymers. A commercially available polyurethane polyol is K-Flex Diol DU 320 (KING INDUSTRIES, 2741 EZ Waddinxveen, The Netherlands). A commercially available cresol formaldehyde condensation copolymer is Novolak AZ 520D (Clariant GmbH, 65926 Frankfurt am Main, Germany).

The preparations according to the invention also comprise at least one polymeric or polymer-bonded polymerization initiator (component C) for the polymerization of component A or components A and B. Suitable initiators are compounds which release the acid or base under acid or base and suitable reaction conditions, for example by heating or actinic radiation.

The term "polymeric or polymer bonded" includes compounds that are themselves part of the polymer backbone or have initiator groups bonded to the polymer backbone. The polymer initiator preferably has a molecular weight of 500 to 1,000,000.

Particularly suitable and preferred are soluble heat activated acids, especially polymeric sulfonic acids such as poly-4-styrene sulfonic acid. The advantage of using thermal acid is that it can lower the temperature at which crosslinking occurs. However, other polymer initiators known to those skilled in the art can also be used.

Preferred lower limits of the formulations are as follows:

Component A: 60% by weight, most preferably 75% by weight.

Component B: 2% by weight, most preferably 5% by weight.

Component C: 0% by weight, most preferably 0.5% by weight.

Preferred upper limits of the formulations are as follows:

Component A: 98% by weight, most preferably 95% by weight.

Component B: 40% by weight, most preferably 25% by weight.

Component C: 5% by weight, most preferably 2% by weight.

The weight percent values given above relate to the total weight of components A, B and C.

Preferably the formulation according to the invention further comprises component D in an amount of 0.5 to 50000% by weight relative to the total weight of the components A, B and C, wherein D dissolves the components A, B and / or C Solvents or mixtures of two or more solvents.

The term dissolution in this case means that a solution, emulsion or suspension of components A, B and / or C can optionally be produced with the aid of one or more emulsifiers or surfactants.

The solvent or dissolution mixture is advantageously compatible with solution coating techniques. Preferred solvents are aliphatic or cycloaliphatic ketones, alcohols and ethers such as cyclohexanone, butanone, isopropyl alcohol (IPA), butanol, ethyl lactate, propylene glycol methyl ether acetate (PGMEA) and propylene glycol methoxy propanol (PGME) as well as mixtures thereof. The solvent or solvent mixture is preferably selected to stabilize the resulting mixture, which also increases its shelf life.

In addition to component D, the formulations according to the invention will comprise at least one surfactant as component E for controlling the surface energy of the formulation and the resulting film to obtain the desired wettability, flowability and adhesion to the substrate and continuous layers. Can be. A further advantage of the surfactant added is the reduction of water absorption into the resulting amine polymer layer. The surfactants are preferably nonionic surfactants such as polyoxyethylene, polyols, siloxanes, fluoronics and tweens.

Preferred lower limits of the formulations are as follows:

Component D: 10% by weight, most preferably 100% by weight.

Component E: 0% by weight, most preferably 0.05% by weight.

Preferred upper limits of the formulations are as follows:

Component D: 10000% by weight, most preferably 5000% by weight.

Component E: 2% by weight, most preferably 0.5% by weight.

The weight percent values given above relate to the total weight of components A, B and C.

In another preferred embodiment of the present application, the formulation according to the invention further comprises ultrafine ceramic particles as component F.

The ultrafine ceramic particles F are included in the formulation in an amount of from 0 to 80% by weight, relative to the total weight of components A, B and C.

The ceramic particles should have an average diameter of less than 200 nm because this is typically the desired maximum thickness of the insulating layer. Preferably, the particles have an average size of less than 100 nm, more preferably about 50 nm to provide easy dispersion in the polymer matrix.

Any suitable material capable of forming the particles into particles with high dielectric properties, such as, but not limited to, high dielectric constant ferroelectric ceramic materials, such as, but not limited to, lead zirconate, barium zirconate, cadmium niobate, barium tie Tannates, and titanates and tantalates of strontium, lead, calcium, magnesium, zinc, and neodymium, and solid solutions thereof. The term ceramic "solid solution" means a ceramic system of two or more components in which ceramic components can be mixed with one another. Ceramic materials useful in the present invention also include barium zirconium titanate (BZT), barium strontium titanate (BST), barium neodymium titanate, lead magnesium niobate, and lead zinc niobate. Each particle can be prepared from a single material or a combination of these materials.

The particles included in the layer may all be uniform or vary in material composition and / or size. In addition, ceramic materials useful in the present invention can be modified with additives such as, but not limited to, oxides of zirconium, bismuth, and niobium. Preferably, the ceramic particles comprise barium titanate.

The components of the preparations according to the invention are also chosen to produce good flow properties, ie high enough to form an adhesive film in a solution coating process and low enough to be filterable and diffusive. The preferred viscosity range of the mixture is 300 to 100000 mPa · s.

In the compounds and components disclosed above and below, substituents, in particular when R ', R ", R"', R ¹ , R ² , R ³ , R ^a , R ^b , R ^c , R ^d are alkyl groups, It may be straight chain or branched. It is preferably straight chain and has 1 to 12 carbon atoms, and therefore preferably methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl or dodecyl. The fluorinated alkyl is preferably C _i F _{2i +1} , i is an integer from 1 to 12, in particular CF ₃ , C ₂ F ₅ , C ₃ F ₇ , C ₄ F ₉ , C ₅ F ₁₁ , C ₆ F ₁₃ , C ₇ F ₁₅ , C ₈ F ₁₇ , C ₉ F ₁₉ , C ₁₀ F ₂₁ , C ₁₁ F ₂₃ or C ₁₂ F ₂₅ .

Cycloalkyl preferably represents an alicyclic group containing 3 to 7 carbon atoms, for example cyclopropyl, cyclopentyl and cyclohexyl.

Aryl preferably denotes aromatic hydrocarbons having 5 to 15 carbon atoms, which may be substituted by one or more heteroatoms O, S and / or N, consist of one, two or three rings, which may be fused to each other . Aryl in the most preferred sense is phenyl.

Alkylaryl preferably contains 5 to 15 C atoms in the aryl moiety and 1 to 12 C atoms in the alkylene moiety, for example benzyl, phenethyl and phenpropyl.

Halogen is F, Cl, Br or I, preferably F or Cl. Halogen is especially F in the case of poly substitution.

The following describes a method for producing a dielectric layer of an electronic device according to the present invention.

In step a) of the method, a substrate is optionally prepared comprising one or more layers or patterns of material having insulation, inversion, conduction, electrons and / or photon functionality. Those skilled in the art can utilize a number of well-known manufacturing techniques of the preferred organic electronic device according to the present invention, as well as conventional electronic devices. For example, the structure of organic electronic devices, materials and techniques for their manufacture are disclosed in detail in the literature cited in the introduction. The process is usually carried out by using a solution of organic and / or polymeric material, for example by the method disclosed below. Molecules of the resulting film can be arranged to achieve anisotropic charge carrier mobility and / or optical dichroism. The organic film is preferably cured by irradiation, for example using a mask in defined portions. The exposed portion undergoes a change in physical and / or chemical properties, for example its conductance or solubility. Unexposed portions may be removed due to their higher solubility. This process allows formation of multiple layers (which may be patterned) with different electronic functionality on top of each other. Advantageously orthogonal solvents are applied, as described in the introduction, in order not to damage the previously formed layer or pattern. In addition to the above, other patterning methods may be used, such as microlithography, stamping or microforming.

A formulation comprising at least one amine derivative as defined above in step b) of the method is formed on the substrate or on a defined portion of the substrate. The formulation is preferably applied as a solution, wherein advantageous solvents and mixtures thereof are disclosed above. Preferred thin layer formation techniques make it possible to process large areas and / or multiple substrates at low cost. Examples include rotational coating, molding, such as microforming in capillaries, and printing techniques such as screen printing, ink jet printing and microcontact printing. Particular preference is given to reel to reel manufacturing processes. These and other processing techniques are described, for example, in Z. Bao, Adv. Mater. 2000, 12, 227-230, Z. Bao et al., J. Mater. Chem. 1999, 9, 1895-1904 and the documents cited above. As mentioned above, the rheological properties of the mixtures of amine derivatives used have a wide range of properties that meet the requirements of the film forming technique by the selection of the components of the mixture, in particular the substituents of the amine derivatives and optionally the multifunctional components and their contents. Can be adjusted within the range.

In step c) polymerization of the thin layer preparation is initiated. Depending on the components of the amine derivative mixture and optionally on the nature of the initiator used, the polymerization is initiated by, for example, increasing the temperature, changing the pH, irradiating with electromagnetic or particle, or reactive compounds. The polymerization reaction is usually a polycondensation of amine derivatives and optionally polyfunctional components, whereby for example water or alcohol is released. The resulting polymeric materials may be polymers, copolymers or graft polymers, which are referred to only above and below as polymers.

Most of the component D or at least the solvent is removed during and / or after performing step c). However, during and / or after the polymerizable mixture is formed on the substrate, it is also possible to remove the solvent before carrying out step c).

The resulting thin layer of amine polymer preferably has a thickness of 0.01 to 50 μm, most preferably 0.1 to 10 μm. The amine polymer material preferably exhibits a resistance of at least 10 ⁺⁸ Ωcm, more preferably at least 10 ⁺¹⁰ Ωcm, most preferably at least 10 ⁺¹¹ Ωcm. The dielectric constant of the material produced is preferably at least 4, most preferably in the range of 4-6.

The thin layer can optionally be patterned after the polymerization step. Suitable techniques are known to those skilled in the art, in particular in the fields of microelectronics and microengineering. Examples of such techniques are etching, lithography, for example photo-, UV- and electron-lithography, laser drawing, stamping and embossing. In addition, the layer can also be patterned by polymerizing only a limited portion of the polymerizable amine mixture. Polymerization in the defined portion can be carried out by initiating the polymerization, for example using a patterned mask and electromagnetic or particle irradiation. The unpolymerized portion of the amine derivative mixture can be removed due to higher solubility compared to the cured portion.

The formation of the dielectric amine polymer layer can be the final step in the fabrication of electronic devices or usually an intermediate step. Thus, one or more further steps, including steps a) and / or b) and c), may follow the process described above. For example, one or more additional layers or patterns of materials having insulating, semiconducting, conducting, electronic and / or photon properties can be applied to the resulting dielectric layer.

Electronic devices obtainable by the process according to the invention and electronic devices comprising the amine polymer material of the invention as dielectrics are also an object of the invention. Preferred devices are microelectronics and / or organic electronic devices and components. Examples include thin film transistors, OFETs, OLEDs, displays, especially large area drive circuits for LCDs, photovoltaic applications and inexpensive storage devices such as smart cards, electronic luggage tags, ID cards, credit cards and tickets.

The polymeric amine material according to the invention can be used as a dielectric by including an insulator material in the device. For example, the polymeric amine material is used as the dielectric layer between the semiconductor material and the gate material in contact with the source and drain electrodes in an OFET. In addition, the amine polymer material of the present invention may also be used as an insulator material for insulating conductive parts of electronic devices. Thus, it can be used as a substrate on which conductive and / or semiconducting materials are deposited on top and / or as an insulating material which covers the layer or pattern having electronic functionality and protects it from short circuits or oxidation.

The entire contents of all applications, patents, and publications mentioned above and later are incorporated herein by reference.

From the above description, those skilled in the art can easily identify the essential features of the present invention and can make various changes and modifications of the present invention to suit various uses and conditions without departing from the spirit and scope of the present invention.

The following examples are presented to further illustrate the invention and should not be construed as limiting the scope or spirit of the invention.

Example

General procedure for a dielectric formulation comprising 2 parts of resin and 1 part of curing agent

Resin (e.g., Cymel® commercially available from Cytec Incorporated) may be prepared from suitable formulations (such as the nature of the device to be manufactured, e.g. structure, geometry, required thickness, durability, stability, process flow, etc.). Determined by). Polymer thermal acid is then added immediately before the spin coating. This step is performed because the viscosity of the formulation increases if the polymer acid is added and not used relatively quickly (within a few hours). Increasing the viscosity is undesirable because it can affect the coating thickness and change the properties of the device.

The resin is spin coated at the desired rotational speed and acceleration to provide the desired film thickness. The film is then baked at high temperature, for example at 100 ° C., depending on the required crosslinking rate.

Example  One

The following polymerizable amine mixtures according to the invention are prepared. The weight percent content relates to the total weight of all components.

1. Resin formulation

Curing Agent Formulation

The individual components are stable over time.

The components are stable upon mixing and homogeneous for several hours. The above shows low to medium viscosity. This flowability property is very good for the application of coating techniques, for example the coating of glass or polyhexylthiophene (which is an organic semiconductor) surface.

2. Preparation of Amine Polymer Material

An amine polymer material is prepared based on the polymerizable amine mixture. The resin and curing agent are thoroughly mixed together in a ratio of 2 to 1, respectively, and the mixture is placed on a flat substrate (in this case a PEN foil), evaporated and contacted the gold source and drain and the organic semiconductor as shown in FIG. 1 above. The layer is spin coated and then diffused onto the substrate by spin coating (increase from 0 to 3000 rpm over a period of 1 second and then held at 3000 rpm for 1 minute). The polymerization and crosslinking are carried out by heating the substrate at 100 ° C. for a period of 1 hour in an air atmosphere. The resulting amine polymer layer has a thickness of about 1 micron.

Using the polymerizable mixture as defined above, an amine polymer layer is prepared according to the procedure described above. The surface of all polymer layers is very flat and hard, but not soft and exhibit excellent bonding. There is no sign of pin-hole formation.

Example  2-Usage Example

2 shows a transistor device for testing a dielectric formulation according to the invention (not to scale). Typically multiple transistors are fabricated on each substrate.

Method of manufacture of transistors:

A special PEN foil with a planarization layer (available from Dupont Teijin films) is used as the device substrate. The substrate is cleaned with IPA before use. Gold source and drain contacts are evaporated on the PEN foil by vacuum evaporation through a shadow mask. The gold typically has a thickness of 50 nm. The distance between the source and drain is typically 130 microns. The organic semiconductor is deposited in a glove box via a spin coating to typically yield a 100 nm film. The dielectric formulation is deposited through a rotary coating such that a thickness of about 1 micron is obtained. The entire device is baked at about 100 ° C. to crosslink the dielectric. The final step is to evaporate the 50 nm layer of gold that will act as the gate of the device.

Transistor device T1 is prepared as described above using a dielectric layer (using polymer acid) as described in Example 1.

For comparison purposes, transistor device T2 is prepared in the same manner as described above, using the same resin and solvent formulations for the dielectric layer but using a nonpolymeric acid initiator (which is paratoluene sulfonic acid).

The critical characteristics of the two transistors are shown in FIG. 3 (curve a = T1, curve b = T2). The plot for T1 shows the same threshold voltage (about + 4V) in both reverse and forward scans. Plots for T2 show different threshold voltages in the forward scan compared to the reverse scan (hysteresis of approximately 6V).

The present invention provides an improved method of making dielectric materials and dielectric layers that does not have the disadvantages of conventional dielectric materials and manufacturing methods.

Claims (19)

At least one crosslinkable organic amine derivative capable of forming a crosslinked polymer on its own and / or with each other and / or with at least one further multifunctional compound in a polymerization or crosslinking reaction, and One or more polymeric or polymeric bound initiators capable of initiating the polymerization or crosslinking reaction Formulation comprising a. The method of claim 1, Formulations characterized in that the amine derivative comprises at least two identical or different groups of the formula Formula 1

Where R ^a is H,-[(CR'R ") _v -CO] _r -R"',-[(CR'R") _v -O-] _r -R"'or-(CR'R") _v -NHZ, R ′, R ″, R ″ ′ are independently of each other H, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, and these groups may be substituted by halogen, Z is H or a protecting group, v is 0 or 1 or more, r is 1 or more, but if v is 0, r is 1. The method of claim 2, At least two groups of formula 1 as defined in claim 2, wherein at least one of the R ^a groups comprises an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms and these groups may be substituted by halogen; Formulations comprising one or more amine derivatives. The method of claim 2 or 3, At least one of R ^a groups is-[(CR'R ") _v -O-] _r -H and R ', R", v and r are as defined in claim 2 Formulations characterized by one or more amine derivatives comprising two or more groups. The method according to any one of claims 1 to 4, Formulations characterized by one or more amine derivatives selected from the group of formulas 1a to 1c: Formula 1a

Formula 1b

Formula 1c

In the above formulas, R ¹ , R ² , R ³ are independently of each other a group of formula (2): Formula 2

R ^a , R ^b , R ^c , and R ^d are each independently of H,-[(CR'R ") _v -CO] _r -R"',-[(CR'R") _v -O-] _r- R "'or-(CR'R") _v -NHZ, R ′, R ″, R ″ ′ are independently of each other H, an alkyl group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms, and these groups may be substituted by halogen, Z is H or a protecting group, v is 0 or 1 or more, r is 1 or more, if v is 0, r is 1, W is O or S, R ³ in addition to the above meanings may be alkyl, cycloalkyl, aryl or alkylaryl groups, which groups are optionally substituted by halogen. The method of claim 5, At least one of the groups R ¹ , R ² , R ³ and / or groups R ^a , R ^b , R ^c , R ^d comprises an alkyl group having 1 to 12 carbon atoms or an alkenyl group having 2 to 12 carbon atoms and these groups A formulation characterized by at least one amine derivative selected from the group of formulas 1a to 1c as defined in claim 5, which may be substituted by halogen. The method according to claim 5 or 6, A formulation characterized by one or more amine derivatives selected from the group of formulas 1a and 1b as defined in claim 5, wherein one, two or three of the groups R ¹ , R ² , R ³ are independently of one another a group of formula 2b: Formula 2b

Where v1 is 0, 1, 2, 3 or 4, v2 is 1, 2, 3 or 4, R ″ 'is an alkyl group having 1 to 12 carbon atoms, wherein one, more or all H atoms may be substituted by halogen. From 50 to 99.5% by weight of component A comprising at least one organic amine derivative as defined in any of claims 2 to 7, 0-50% by weight of component B comprising one or more multifunctional compounds capable of reacting with one or more compounds of A to form a crosslinked polymer, and 0-10% by weight of component C comprising component A or at least one polymeric or polymer-bonded initiator for the polymerization of components A and B Formulations comprising a. The method according to any one of claims 1 to 8, The multifunctional compound of component B is selected from organic compounds having at least two functional groups in the group consisting of —OH, —NH ₂ , —COOH and reactive derivatives thereof, and reacts with at least one component of component A to crosslink To form a polymer. The method according to any one of claims 1 to 9, Wherein the polymeric or polymeric bound initiator is selected from soluble heat activated acids having a molecular weight of at least 500. The method according to any one of claims 1 to 10, Formulations characterized in that the polymeric or polymer bound initiator is poly-4-styrene sulfonic acid. The method according to any one of claims 1 to 11, Further comprises component D, which is a solvent capable of dissolving the components A, B and / or C or a mixture of two or more solvents, in an amount of 0.5 to 50000% by weight relative to the total weight of components A, B and C Formulation. The method according to any one of claims 1 to 12, Further comprising ultrafine ceramic particles as component F. The method of claim 13, Wherein said ultrafine ceramic particles F are contained in the polymerizable amine mixture in an amount of 0 to 80% by weight relative to the total weight of components A, B and C. Crosslinked polymeric material obtainable by polymerization of the formulation according to claim 1. Organic field effect transistors (OFETs), thin film transistors (TFTs), components of integrated circuits (ICs), radio frequency identification (RFID) tags, organic light emitting diodes (OLEDs), electroluminescent displays, flat panel displays, backlights, photodetectors, sensors In a logic circuit, a memory element, a capacitor, a photovoltaic (PV) cell, a charge injection layer, a Schottky diode, a planarization layer, an antistatic film, a conductive substrate or pattern, a photoconductor, or an electrophotographic element. Use of the agent or crosslinked polymer according to claim 15. a) manufacturing a substrate optionally comprising one or more layers or patterns of a material having insulation, inversion, conduction, electrons and / or photon functionality, b) forming a thin layer of the formulation of any one of claims 1 to 14 on the substrate or on a confined region of the substrate, and c) initiating the polymerization of said thin layer formulation. A method of manufacturing a dielectric layer of an electronic device, comprising. An electronic device comprising the polymeric material according to claim 15 as a dielectric. An electronic device obtainable by the method according to claim 17.

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