KR20060058454A - A thin film transistor, a method for preparing the same and a flat panel display therewith - Google Patents

Abstract

The present invention is a gate electrode; Source and drain electrodes insulated from the gate electrode; An organic semiconductor layer insulated from the gate electrode and electrically connected to the source and drain electrodes; And an insulating layer that insulates the gate electrode from the source and drain electrodes or the organic semiconductor layer, and has a self-assembly molecular layer between the source and drain electrodes and the organic semiconductor layer. The magnetic molecular assembly layer is composed of a silane-based compound having at least a primary amino group at its end and an aromatic compound having an electron withdrawing group and a condensation reactive group. A thin film transistor comprising a condensation reaction product, a method of manufacturing the thin film transistor, and a flat panel display device having the thin film transistor. The thin film transistor of the present invention may have an improved contact resistance between the source and drain electrodes and the organic semiconductor layer and a high coupling force between the source and drain electrodes and the magnetic molecule assembly layer, thereby obtaining a flat panel display having improved reliability. have.

Description

A thin film transistor, a method for preparing the same and a flat panel display therewith}

1 is a cross-sectional view showing the structure of a thin film transistor according to an embodiment of the present invention,

2 is a cross-sectional view illustrating a structure of a thin film transistor according to another embodiment of the present invention;

3 is a cross-sectional view when an embodiment of the thin film transistor of the present invention is applied to an organic light emitting display device.

<Brief description of the main parts of the drawing>

11, 21: substrate 12, 22: gate electrode

13, 23: insulation layers 14, 24: source and drain electrodes

15, 25: organic semiconductor layer 16, 26: magnetic molecular assembly layer

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film transistor, a method for manufacturing the same, and a flat panel display device having the same, and more particularly, a contact resistance between an organic semiconductor layer and a source and drain electrode is reduced, and between a source and drain electrode and a magnetic molecule assembly layer. A thin film transistor having an increased coupling force and a flat panel display device having the same.

Thin film transistors used in flat panel display devices such as liquid crystal display devices, organic electroluminescent display devices, or inorganic electroluminescent display devices (hereinafter referred to as TFTs) are used to drive switching elements and pixels that control the operation of each pixel. Used as a drive element.

Such a TFT has a semiconductor layer having a source / drain region doped with a high concentration of impurities and a channel region formed between the source / drain regions, the gate being insulated from the semiconductor layer and located in a region corresponding to the channel region. And a source / drain electrode in contact with the source / drain region, respectively.

However, the source / drain electrodes are usually made of a metal having a low work function to smoothly flow electric charges. Due to the high contact resistance of the region where the metal and the semiconductor layer are in contact, the characteristics of the device are deteriorated. There is a problem that power consumption is increased.

The organic thin film transistor, which is being actively researched recently, has an advantage that a plastic substrate can be used by having an organic semiconductor layer that can be formed in a low-pore process, but the contact resistance is increased at the point where the source and drain electrodes are in contact with the semiconductor layer. High still has the problem. Among various methods for improving the contact resistance, there is a method using a self-assembled monolayer (hereinafter also referred to as a "SAM layer"). The magnetic molecular assembly layer is described, for example, in Korean Patent Publication No. 2001-0026674.

However, conventional thin film transistors have not achieved satisfactory contact resistance reduction, and there is still a need for improvement.

The present invention has been devised to solve the above problems, and provides a thin film transistor having improved contact resistance between the organic semiconductor layer and the source and drain electrodes, a method of manufacturing the thin film transistor, and a flat panel display device having the same. The purpose is.

In order to achieve the above object of the present invention, the first aspect of the present invention,

A gate electrode;

Source and drain electrodes insulated from the gate electrode;

An organic semiconductor layer insulated from the gate electrode and electrically connected to the source and drain electrodes; And

An insulating layer insulating said gate electrode from a source and drain electrode or an organic semiconductor layer,

A self-assembly molecular layer is provided between the source and drain electrodes and the organic semiconductor layer, the magnetic molecular assembly layer having a primary amino group at least at the end. And a condensation reaction product of an aromatic compound having an electron withdrawing group and a condensation reactive group.

According to another object of the present invention, the second aspect of the present invention,

Forming an insulating layer to cover the gate electrode provided on the insulating substrate;

Forming source and drain electrodes at predetermined positions corresponding to both ends of the gate electrode on the insulating layer;

Forming a magnetic molecular assembly layer on the source and drain electrodes; And

Forming an organic semiconductor layer to cover the magnetic molecular assembly layer;

The method of claim 1, wherein the step of forming the magnetic molecular assembly layer is performed by sequentially applying a silane compound having a primary amino group and an aromatic compound having an electron attracting group and a condensation reaction group at least at an end thereof to condensation reaction. to provide.

According to still another object of the present invention, the third aspect of the present invention,

Forming a source and a drain electrode on the insulating substrate;

Forming a magnetic molecular assembly layer on the source and drain electrodes;

Forming an organic semiconductor layer on the magnetic molecular assembly layer;

Forming an insulating layer to cover the organic semiconductor layer; And

Forming a gate electrode at a predetermined position on the insulating layer to correspond to the source and drain electrodes;

The method of claim 1, wherein the step of forming the magnetic molecular assembly layer is performed by sequentially applying a silane compound having a primary amino group and an aromatic compound having an electron attracting group and a condensation reaction group at least at an end thereof to condensation reaction. to provide.

In order to achieve another object of the present invention, a fourth aspect of the present invention includes a thin film transistor as described above or a thin film transistor manufactured according to the thin film transistor manufacturing method as described above in each pixel, Provided is a flat panel display in which a pixel electrode is connected to a source electrode or a drain electrode.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail.

1 is a cross-sectional view illustrating a thin film transistor 10 according to an exemplary embodiment of the present invention.

In FIG. 1, the substrate 11 may be a glass substrate or a plastic substrate. The gate electrode 12 of a predetermined pattern is formed on the substrate. The gate electrode 12 may be made of, for example, a metal or an alloy of a metal such as Au, Ag, Cu, Ni, Pt, Pd, Al, Mo, or Al: Nd, Mo: W alloy, but is not limited thereto. It doesn't happen. An insulating layer 13 is provided on the gate electrode 12 to cover the gate electrode 12. The insulating layer 13 may be made of an inorganic material such as a metal oxide or metal nitride, or may be made of an organic material such as an insulating organic polymer, but is not limited thereto.

Source and drain electrodes 14a and 14b are formed on the insulating layer 13, respectively. As shown in FIG. 1, the source and drain electrodes 14a and 14b may be overlapped with a portion of the gate electrode 12, but are not necessarily limited thereto.

The source and drain electrodes 14a and 14b may typically use noble metals of 5.0 eV or more in consideration of a work function with a material forming an organic semiconductor layer. Meanwhile, the source and drain electrodes 14a and 14b of the present invention may be made of an oxidizable metal, in particular, an oxidizable metal or an oxide of a metal, in consideration of the bonding force with the magnetic molecular assembly layer to be provided thereon. In particular, when the source and drain electrodes 14a and 14b are made of an oxidizable metal, at least a part or more of the surfaces of the source and drain electrodes may be formed of an oxide of a metal constituting the source and drain electrodes. That is, the source and drain electrodes may be made of an oxidizable metal, and oxides of the metals may be provided on surfaces of the source and drain electrodes in contact with the magnetic molecular assembly layer according to the present invention. As a non-limiting example of the material forming the source and drain electrodes, in addition to Au, Pd, Pt, Ni, Rh, Ru, Ir, Os, two or more metals such as Al, Mo, Al: Nd alloy, MoW alloy, etc. It is possible to use an alloy made of, and as the oxide of the metal may be used ITO, IZO, NiO, Ag ₂ O, In ₂ O ₃ -Ag ₂ O, CuAlO ₂ , SrCu ₂ O ₂ and ZnO doped with Zr, It is not limited. It goes without saying that two or more of the metals or metal oxides described above can be used in combination.

On the other hand, the organic semiconductor layer 15 is entirely formed on the source and drain electrodes 14a and 14b. Examples of the organic semiconductor material forming the organic semiconductor layer 15 include pentacene, tetracene, anthracene, naphthalene, alpha-6-thiophene and alpha-4-ti. Offene, perylene and its derivatives, rubrene and its derivatives, coronene and its derivatives, perylene tetracarboxylic diimide and its derivatives, perylenetetracarb Perylene tetracarboxylic dianhydride and its derivatives, polythiophene and its derivatives, polyparaphenylenevinylene and its derivatives, polyparaphenylene and its derivatives, polyfluorene and its derivatives, polythiophenevinyl Enes and derivatives thereof, polythiophene-heterocyclic aromatic copolymers and derivatives thereof, oligoacenes and derivatives thereof of naphthalene, oligothiophenes and derivatives thereof of alpha-5-thiophene, with or without metals Rossi not and the like and derivatives thereof, Pyro mellitic dianhydride and its derivatives, pyromellitic Pyro tick diimide and derivatives thereof may be used.

A magnetic molecular assembly layer 16 is provided between the source and drain electrodes 14a and 14b and the organic semiconductor layer 15. The magnetic molecular assembly layer 16 is a silane-based compound having a primary amino group at least at its terminal, an aromatic compound having an electron withdrawing group, and a condensation reactive group. condensation reaction product of a cyclice compound).

The silane compound may have the following formula (1);

<Formula 1>

In Formula 1, R ₁ has an amino group (-NH ₂ group) capable of causing a condensation reaction with an aromatic compound having an electron withdrawing group and a condensation reaction group.

,

,

또는

일 수 있다.R ₁ is an —NH ₂ group; Or a C _1-5 alkyl group, C _6-10 aryl group or C _7-11 arylalkyl group substituted with an N (A ₁ ) (A ₂ ) group or a —CH ₂ N (A ₁ ) (A ₂ ) group have. In this case, A ₁ and A ₂ may be independently hydrogen, —CH ₂ CH ₂ NH ₂ or —CH ₂ CH ₂ NH (CH ₂ CH ₂ NH ₂ ). In particular, R ₁ is —NH ₂ , —CH ₂ CH ₂ CH ₂ NH ₂ ,

,

,

or

Can be.

In Formula 1, R ₂ and R ₃ may be independently a linear or branched C _1-10 alkyl group or C _1-10 alkoxy group. In particular, R ₂ and R ₃ may independently be linear or branched C _1-6 alkyl groups or C _1-6 alkoxy groups. Among these, it is preferable that it is an ethoxy group.

R ₄ may be a linear or branched C _1-10 alkoxy group. In particular, R ₄ may be a linear or branched C _1-6 alkoxy group. Among these, it is preferable that it is an ethoxy group.

Specific examples of the silane compound having the general formula (1) include, for example, triethoxyaminosilane, triethoxy- (3-aminopropyl) silane, triethoxy- (4-aminophenyl) silane, and triethoxy -{(N-2-aminoethyl) -3-aminopropyl} silane, triethoxy {3- (2- (2-aminoethyl) aminoethylamino) propyl} silane, triethoxy {2- (4- ((2-aminoethyl) aminomethyl) phenyl) ethyl} silane and the like, but are not limited thereto.

The aromatic compound having the electron withdrawing group and the condensation reaction group may have the following Chemical Formula 2 or 3:

<Formula 2>

Z ₁ -QZ ₂

<Formula 3>

Z ₁ -QX

In Formulas 2 and 3, Z ₁ and Z ₂ are independently a C _6-10 aryl group; C _7-11 arylalkyl group; Or a C _4-6 heteroaryl group comprising at least one hetero atom selected from the group consisting of N, O, P and S; Or Z ₁ and Z ₂ may be linked or fused to each other to form a C _6-13 carbocyclic system having 1 to 3 rings.

At least one hydrogen atom of at least one of Z ₁ and Z ₂ is substituted with at least one substituent A. The substituent A is an electron withdrawing group, and the contact resistance between the source and drain electrodes and the organic semiconductor layer may be significantly reduced by the magnetic molecular assembly layer containing the same. A is, for example, -NO ₂ , -F, -Cl, -Br; And it may be selected from the group consisting of C _1-5 alkyl group and C _6-10 aryl group substituted with one or more selected from the group consisting of -NO ₂ , -F, -Cl and -Br. In particular, A can be an —NO ₂ , —F, —CF ₃ or an aminophenyl group.

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또는

일 수 있다. 이 때, 상기 m은 1 내지 5의 정수이고; 상기 n은 1 내지 4의 정수이고; 상기 p는 1 내지 6의 정수이고; 상기 q는 1 내지 3의 정수일 수 있다. 한편, 상기 별표는 화학식 2 또는 3 중 Q와 결합되는 위치를 나타내는 것이다.More specifically, the carbocyclic system formed by Z ₁ , Z ₂ and Z ₁ and Z ₂ connected or fused to each other independently,

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or

Can be. Wherein m is an integer from 1 to 5; N is an integer from 1 to 4; P is an integer from 1 to 6; Q may be an integer of 1 to 3. On the other hand, the asterisk is to indicate the position bonded to Q in the formula (2) or 3.

In Formula 2 or 3, Q may be -CO-, -SO2- or-(OC) O (CO)-.

On the other hand, in Formula 2 or 3, X may be -H, -F, -Cl, -Br or -OH.

In Formula 2 or 3, Q or Q-X may correspond to a moiety capable of condensation reaction with an amino group of a silane compound as described above.

More specifically, the aromatic compound may have a formula selected from the group consisting of Formula 4-24:

<Formula 4> <Formula 5>

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<Formula 6> <Formula 7>

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<Formula 8> <Formula 9>

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<Formula 10> <Formula 11>

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<Formula 12> <Formula 13>

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<Formula 14> <Formula 15>

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<Formula 16> <Formula 17>

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<Formula 18> <Formula 19>

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<Formula 20> <Formula 21>

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<Formula 22> <Formula 23>

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및

,

And

<Formula 24>

.

.

In the above formulas, m, n, p and q are the same as described above.

More preferably, the aromatic compound having the formula (2) or (3) is 2-nitrobenzaldehyde, 3-nitrobenzaldehyde, 4-nitrobenzaldehyde, 2,6-dinitrobenzaldehyde, 1-nitro-2-naphthaldehyde, 2,3, 4-trifluorobenzaldehyde, 2,3,5-trifluorobenzaldehyde, 2,3,6-trifluorobenzaldehyde, 2,4,5-trifluorobenzaldehyde, 3,4,5-trifluorobenzaldehyde , 2-trifluoromethylbenzaldehyde, 3-trifluoromethylbenzaldehyde, 4-trifluoromethylbenzaldehyde, 5-nitro-2-furfural, 5- (2-nitrophenyl) furfural, 5- (3- Nitrophenyl) furfural, 5- (4-nitrophenyl) furfural, 5-nitro-2-thiophene carboxaldehyde, 3-nitrobenzophenone, 4-nitrobenzoic acid, 3-nitrobenzoic acid, 4-nitrobenzoic acid, 2,4-dinitrobenzoic acid, 3,5-dinitrobenzoic acid, 2-nitrobenzoyl chloride, 3-nitrobenzoyl chlora De, 4-nitrobenzoyl chloride, 2,3,4-trifluorobenzoyl chloride, 2,3,6-trifluorobenzoyl chloride, 4-trifluoromethylbenzoyl chloride, 2-nitrobenzenesulfonyl chloride, 3 -Nitrobenzenesulfonyl chloride, 4-nitrobenzenesulfonyl chloride, 2,4-dinitrobenzenesulfonyl chloride, 2-nitro-alpha-toluenesulfonyl chloride, 2-nitro-4- (trifluoromethyl) benzene Sulfonyl chloride, 2,3,4-trifluorobenzenesulfonyl chloride, 3,4,5-trifluorobenzenesulfonyl chloride, 4-trifluoromethylbenzenesulfonyl chloride, 3-nitro-1,8 It may include, but is not limited to, naphthalic anhydride, 4-nitro-1,8-naphthalic anhydride, 3-nitrophthalic anhydride, 4-nitrophthalic anhydride, and the like.

Specific examples of the C _1-5 alkyl group in the chemical formula of the present invention include methyl, ethyl, propyl, isobutyl, sec-butyl and the like.

Aryl groups in the formulas of the present invention may be used alone or in combination to mean a carbocycle aromatic system comprising one or more rings, which rings may be attached or fused together in a pendant manner. The term aryl includes aromatic radicals such as phenyl, naphthyl, tetrahydronaphthyl.

Heteroaryl group in the formula of the present invention means a monocyclic or bicyclic aromatic divalent organic compound containing at least one heteroatom selected from N, O, P or S, the remaining ring atom is C.

In the formula of the present invention, an arylalkyl group refers to a substituent including an aryl group or a heteroaryl group as described above at the end of the alkyl group as described above.

The magnetic molecular assembly layer 16 of the present invention consists of a condensation reaction product of a silane compound having a primary amino group at least at the end as described above, and an aromatic compound having electron attraction and condensation reaction groups. The condensation reaction product can form an Si—O bond by combining with an —OH group, in particular of a source and drain electrode of an oxidizable metal, in particular an oxidizable metal or metal oxide. The Si-O bond has a significantly higher bonding strength than the noble metal-S bond between a source and drain electrode made of a noble metal such as Au, and a magnetic molecule assembly layer containing a -SH group (thiol group).

In the case of the noble metal-S bond, a dissociation reaction occurs reversibly at a temperature of about 90 ° C., and at a temperature of about 100 ° C. or more, the magnetic molecular assembly layer may desorption-decompose from the source and drain electrode surfaces of the noble metal. The bond between the source and drain electrodes and the magnetic molecular assembly layer by the noble metal-S bond is known to be very weak (B. Michel, et al., Langmuir, 1994, 10, 4103; JB Schlenoff, et al., J. Am Chem. Soc., 1995, 117, 12528; TR Lee, et al., J. Phys. Chem. B, 2000, 104, 8192).

However, the Si-O bonds formed between the magnetic molecule assembly layer of the present invention and the source and drain electrodes are known to be very strong bonds, such as being not destroyed even at a temperature of 450 ° C. or higher in an oxygen-free atmosphere (J. Sagiv, et al., J. Phys. Chem., 1986, 90, 3054: F. Roudelez, et al., Appl. Phys. Lett., 1993, 62, 2256).

Therefore, the thin film transistor according to the present invention has a very good bonding force between the source and drain electrodes and the magnetic molecule assembly layer, and as a result, durability, lifespan, and the like can be improved.

The thin film transistor of the present invention may be formed to not only have a stacked structure as described above but also have various stacked structures. For example, the thin film transistor of the present invention, as shown in Figure 2, the source and drain electrodes 14a, 14b, the magnetic molecular assembly layer 16, the organic semiconductor layer 15, the insulating layer 13 and the gate The electrodes 12 may have a stacked structure.

The thin film transistor of the present invention can be formed in various ways. According to one embodiment of the method of manufacturing a thin film transistor according to the present invention, forming an insulating layer to cover the gate electrode provided on the insulating substrate; Forming source and drain electrodes at predetermined positions corresponding to both ends of the gate electrode on the insulating layer; Forming a magnetic molecular assembly layer on the source and drain electrodes; And forming an organic semiconductor layer to cover the magnetic molecular assembly layer, wherein the forming of the magnetic molecular assembly layer has a silane-based compound having a primary amino group at least at the terminal, an electron attracting group and a condensation reaction group; It can carry out by applying an aromatic compound sequentially and condensation reaction.

Apart from this, according to another embodiment of the manufacturing method of the thin film transistor of the present invention, forming a source and drain electrode on an insulating substrate; Forming a magnetic molecular assembly layer on the source and drain electrodes; Forming an organic semiconductor layer on the magnetic molecular assembly layer; Forming an insulating layer to cover the organic semiconductor layer; And forming a gate electrode at a predetermined position in the upper portion of the insulating layer corresponding to the source and drain electrodes. The silane-based compound and the electron having a primary amino group at least at the end of the magnetic molecular assembly layer forming step may be formed. The aromatic compound having the drag and condensation reaction groups may be applied sequentially to carry out the condensation reaction.

The forming of the source and drain electrodes may further include oxidizing the source and drain electrode surfaces when the source and drain electrodes are formed of an oxidizable metal. This takes into account the bonding force with the magnetic molecular assembly layer to be formed later. Surface oxidation of the source and drain electrodes can be performed in a variety of ways. For example, a method of annealing the surfaces of the source and drain electrodes under an atmospheric atmosphere, preferably an oxygen atmosphere, a method of treating the surfaces of the source and drain electrodes with a gas, preferably an oxygen plasma, or hydrogen peroxide on the surfaces of the source and drain electrodes Chemical treatment with an oxidizing agent such as water may be used, but is not limited thereto.

On the other hand, the material constituting the magnetic molecular assembly layer is a condensation reaction product of an aromatic compound having a silane-based compound having a primary amino group at least at the terminal and an electron attracting group and a condensation reaction group as described above. The silane compound having a primary amino group at least at the terminal may be a compound represented by Chemical Formula 1, and the aromatic compound may be a compound represented by Chemical Formula 2 or 3. Detailed description thereof will be omitted since it is the same as described above.

The magnetic molecular assembly layer forming step may be, for example, first applying a silane compound having a primary amino group at least at an end on a source and a drain electrode, and then applying the aromatic compound thereon, and condensing the compounds. It may be carried out in a variety of ways, such as.

In the magnetic molecular assembly layer forming step, the silane-based compound and the aromatic compound may be applied to the insulating layer or the upper substrate according to the structure of the thin film transistor, in addition to the upper portion of the source and drain electrodes. Since the magnetic molecule assembly layer according to the present invention is preferably provided only on the source and drain electrodes, the magnetic molecule assembly layer formed outside the top of the source and drain electrodes may be further removed.

First, when a material constituting an insulating layer or a substrate other than the top of the source and drain electrodes does not bond with the silane compound, the silane compound applied to the insulating layer or the substrate other than the top of the source and drain electrodes may be a solvent, for example. For example, it can be easily removed only by washing with acetone or the like.

On the other hand, when a material forming an insulating layer or a substrate other than the upper portion of the source and drain electrodes is combined with the silane-based compound, additional means for removing the material is required. In consideration of this, the step of forming the magnetic molecular assembly layer further includes applying a silane compound having a primary amino group at least at the end thereof, and then removing the silane compound applied to an area except the upper part of the source and drain electrodes. can do. Alternatively, the magnetic molecular assembly layer forming step may be performed by applying a silane-based compound having a primary amino group and an aromatic compound having an electron withdrawing and condensation reaction group at least at the end thereof, and then applying the region to the region except the upper part of the source and drain electrodes. The method may further include removing a condensation reaction product of the silane compound and the aromatic compound.

At this time, in order to remove the silane-based compound or the condensation reaction product of the silane-based compound and the aromatic compound, various methods may be used. For example, an insulating layer other than the source and drain electrodes or the silan-based compound or the silane-based compound on the substrate may be used. These can be removed by irradiating a condensation reaction product of the aromatic compound with light such as UV. To this end, various methods may be used, such as irradiation may be performed using a predetermined photomask, or irradiation may be performed on the back side of the substrate on which the source and drain electrodes are to be provided.

The thin film transistor having the structure described above may be provided in a flat panel display such as an LCD or an organic light emitting display.

3 illustrates the application of the TFT to an organic light emitting display device which is an embodiment of a flat panel display.

FIG. 3 shows one subpixel of an organic electroluminescent display, each of which is provided with an organic electroluminescent element (hereinafter referred to as an "EL element") as a self-luminous element, and at least a thin film transistor. One or more are provided.

Such an organic light emitting display device has various pixel patterns according to the color of light emitted by the EL element OLED, and preferably includes red, green, and blue pixels.

As illustrated in FIG. 3, a gate electrode 22 having a predetermined pattern is formed on the substrate 21, and an insulating layer 23 is formed to cover the gate electrode 22. Source and drain electrodes 24a and 24b are formed on the gate insulating film 23, respectively. The magnetic molecular assembly layer 26 is provided on the source and drain electrodes 24a and 24b. Detailed description of the compound constituting the magnetic molecular assembly layer 26 is as described above, and will be omitted.

An organic semiconductor layer 25 is covered over the magnetic molecular assembly layer 26, and the organic semiconductor layer 25 includes a source / drain region and a channel region connecting the source / drain region. .

After the organic semiconductor layer 25 is formed, the passivation layer 27 is formed to cover the thin film transistor 20. The passivation layer 27 may be formed of a single layer or a plurality of layers, and may be formed of an organic material, an inorganic material, or an organic / inorganic composite.

The organic light emitting film 32 of the EL element 30 is formed on the passivation layer 27 in accordance with the pixel definition film 28.

The EL element 30 emits red, green, and blue light in accordance with the flow of current to display predetermined image information. One of the source and drain electrodes 24a and 24b of the thin film transistor 20 is provided. A pixel electrode 31 connected to the pixel electrode, an opposing electrode 33 provided to cover the entire pixel, and an organic light emitting film 32 disposed between the pixel electrode 31 and the opposing electrode 33 to emit light. do. The present invention is not necessarily limited to the above structure, and the structures of various organic light emitting display devices may be applied as it is.

The organic light emitting film 32 may be a low molecular or polymer organic film. When the low molecular organic film is used, a hole injection layer (HIL), a hole transport layer (HTL), and an emission layer (EML) may be used. ), An electron transport layer (ETL), an electron injection layer (EIL), or the like, may be formed by stacking a single or a complex structure, and the usable organic material may be copper phthalocyanine (CuPc). , N, N-di (naphthalen-1-yl) -N, N'-diphenyl-benzidine (N, N'-Di (naphthalene-1-yl) -N, N'-diphenyl-benzidine: NPB), Various applications are possible, including tris-8-hydroxyquinoline aluminum (Alq3). These low molecular weight organic films are formed by the vacuum deposition method.

In the case of the polymer organic film, the structure may include a hole transporting layer (HTL) and a light emitting layer (EML). In this case, PEDOT is used as the hole transporting layer, and polyvinylvinylene (PPV) and polyfluorene are used as the light emitting layer. Polymer organic materials such as (Polyfluorene) are used and can be formed by screen printing or inkjet printing.

The organic layer as described above is not necessarily limited thereto, and various embodiments may be applied.

The pixel electrode 31 functions as an anode electrode, and the counter electrode 33 functions as a cathode electrode. Of course, the polarities of the pixel electrode 31 and the counter electrode 33 may be reversed. .

In the case of the liquid crystal display, unlike this, a lower alignment layer (not shown) covering the pixel electrode 31 is formed, thereby completing the manufacture of the lower substrate of the liquid crystal display.

As described above, the thin film transistor according to the present invention may be mounted in each subpixel as shown in FIG. 3, or may be mounted in a driver circuit (not shown) in which an image is not implemented.

The organic electroluminescent display is suitable for using a flexible plastic substrate as the substrate 21.

Hereinafter, the present invention will be described in more detail using examples.

Example

A substrate having a gate electrode made of MoW (thickness of 100 nm), an insulating layer made of SiO ₂ (thickness of 200 nm), and a source and drain electrode made of MoW (thickness of 100 nm) whose surface was oxidized was prepared. The substrate was immersed in triethoxy- (3-aminopropyl) silane compound solution (50 mM anhydrous toluene) for 3 hours, washed sequentially with toluene, acetone and isopropanol, and dried and cured at 120 (C for 1 hour). A triethoxy- (3-aminopropyl) silane compound was coated on the surface of the source and drain electrodes, and then the substrate on which the silane compound coating layer was formed was slowly stirred with 4-nitrobenzaldehyde (0.5 w / v% anhydrous). After immersion in methanol), acetic acid as a dehydration condensation catalyst and molecular sieve as a dehydrating agent (0.4 nm) were added, stirred at 50 (C for 3 hours, washed sequentially with toluene and methanol, and dried at 120 (C for 1 hour). The silane compound and 4-nitrobenzaldehyde were subjected to a dehydration condensation reaction The source and drain in the layer formed as a result of the silane compound and 4-nitrobenzaldehyde dehydration condensation reaction. UV irradiation (1000 mJ / cm ² ) was carried out under an atmospheric atmosphere using a photomask having a predetermined pattern in an area where no electrode was provided, as a result, on the tree only above the source and drain electrodes not irradiated with UV. The layer formed as a result of the condensation reaction of the oxy- (3-aminopropyl) silane compound with 4-nitrobenzaldehyde was then left, followed by the triethoxy- (3-aminopropyl) silane compound formed on the MoW source and drain electrodes. An organic semiconductor layer was formed by depositing pentacene (70 nm) so as to cover the condensation reaction product of nitrobenzaldehyde, thereby manufacturing an organic thin film transistor according to the present invention.

According to the present invention as described above, it is possible to obtain a thin film transistor in which the contact resistance between the organic semiconductor layer and the source and drain electrodes is reduced, and the bonding force between the source and drain electrodes and the magnetic molecule assembly layer is increased. By using the thin film transistor, a flat panel display device having high reliability can be manufactured.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (16)

A gate electrode; Source and drain electrodes insulated from the gate electrode; An organic semiconductor layer insulated from the gate electrode and electrically connected to the source and drain electrodes; And An insulating layer insulating said gate electrode from a source and drain electrode or an organic semiconductor layer, A self-assembly molecular layer is provided between the source and drain electrodes and the organic semiconductor layer, the magnetic molecular assembly layer having a primary amino group at least at the end. And a condensation reaction product of an aromatic compound having an electron withdrawing group and a condensation reactive group. The thin film transistor of claim 1, wherein the silane-based compound has Formula 1; <Formula 1>

In Formula 1, R ₁ is an —NH ₂ group; Or a C _1-5 alkyl group, C _6-10 aryl group or C _7-11 aralkyl group substituted with a N (A ₁ ) (A ₂ ) group or a —CH ₂ N (A ₁ ) (A ₂ ) group; A ₁ and A ₂ are independently hydrogen, —CH ₂ CH ₂ NH ₂ or —CH ₂ CH ₂ NH (CH ₂ CH ₂ NH ₂ ); R ₂ and R ₃ are independently a linear or branched C _1-10 alkyl group or C _1-10 alkoxy group; R ₄ is a linear or branched C _1-10 alkoxy group. The compound of claim 2, wherein R ₁ is —NH ₂ , —CH ₂ CH ₂ CH ₂ NH ₂ ,

,

,

or

It is a thin film transistor characterized by the above-mentioned. The thin film transistor of claim 1, wherein the aromatic compound has the following Chemical Formula 2 or 3: <Formula 2> Z ₁ -QZ ₂ <Formula 3> Z ₁ -QX In Formulas 2 and 3, Z ₁ and Z ₂ are independently a C _6-10 aryl group; C _7-11 aralkyl group; Or a C _4-6 heteroaryl group comprising at least one hetero atom selected from the group consisting of N, O, and S; Or Z ₁ and Z ₂ are connected or fused to each other to form a C _6-13 carbocyclic system having 1 to 3 rings; At least one hydrogen atom of at least one of Z ₁ and Z ₂ is substituted with at least one substituent A; A is -NO ₂ , -F, -Cl, -Br; And a C _1-5 alkyl group and C _6-10 aryl group substituted with at least one selected from the group consisting of -NO ₂ , -F, -Cl and -Br; Q is -CO-, -SO2- or-(OC) O (CO)-; X is -H, -F, -Cl, -Br or -OH. The thin film transistor according to claim 4, wherein A is -NO ₂ , -F, -CF _3, or an aminophenyl group. The carbocyclic system of claim 4, wherein Z ₁ , Z _2, and Z ₁ and Z ₂ are formed by being connected or fused to each other independently,

,

,

,

,

,

,

,

,

,

,

or

ego; M is an integer from 1 to 5; N is an integer from 1 to 4; P is an integer from 1 to 6; Q is an integer of 1 to 3; Wherein the asterisk is a thin film transistor, characterized in that for indicating the position combined with Q in the formula (2) or (3). The compound of claim 4, wherein the aromatic compound has a formula selected from the group consisting of Formula 4-24; In the formula, m is an integer of 1 to 5; n is an integer from 1 to 4; p is an integer from 1 to 6; q is an integer of 1 to 3, wherein the thin film transistor: <Formula 4> <Formula 5>

,

, <Formula 6> <Formula 7>

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, <Formula 8> <Formula 9>

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, <Formula 10> <Formula 11>

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, <Formula 12> <Formula 13>

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, <Formula 14> <Formula 15>

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, <Formula 16> <Formula 17>

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, <Formula 18> <Formula 19>

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, <Formula 20> <Formula 21>

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, <Formula 22> <Formula 23>

,

And <Formula 24>

The thin film transistor of claim 1, wherein a surface of the source and drain electrodes in contact with the magnetic molecule assembly layer is formed of an oxide of a material forming the source and drain electrodes. The method of claim 1, wherein the source and drain electrodes are Au, Pd, Pt, Ni, Rh, Ru, Ir, Os, Al, Mo, Al: Nd alloy, MoW alloy, ITO, IZO, NiO, Ag ₂ O, A thin film transistor comprising at least one selected from the group consisting of ZnO doped with In ₂ O ₃ -Ag ₂ O, CuAlO ₂ , SrCu ₂ O _2, and Zr. The organic semiconductor layer of claim 1, wherein the organic semiconductor layer is pentacene, tetracene, anthracene, naphthalene, alpha-6-thiophene, alpha-4-thiophene, perylene perylene and its derivatives, rubrene and its derivatives, coronene and its derivatives, perylene tetracarboxylic diimide and its derivatives, perylene tetracarboxylic dihydride Perylene tetracarboxylic dianhydride and its derivatives, polythiophene and its derivatives, polyparaphenylenevinylene and its derivatives, polyparaphenylene and its derivatives, polyfluorene and its derivatives, polythiophenevinylene and its derivatives , Polythiophene-heterocyclic aromatic copolymers and derivatives thereof, oligoacenes and derivatives thereof of naphthalene, oligothiophenes and derivatives thereof of alpha-5-thiophene, phthalocyanines with or without metals and these Derivatives, Pyro pyromellitic dianhydride and a derivative thereof, and pi pyromellitic diimide ticks and their thin film transistor characterized in that it includes at least one of a derivative. Forming an insulating layer to cover the gate electrode provided on the insulating substrate; Forming source and drain electrodes on predetermined positions corresponding to both ends of the gate electrode on the insulating layer; Forming a magnetic molecular assembly layer on the source and drain electrodes; And Forming an organic semiconductor layer to cover the magnetic molecular assembly layer; The thin film, characterized in that the magnetic molecular assembly layer forming step is carried out by applying a silane-based compound having a primary amino group and an aromatic compound having an electron attracting group and a condensation reaction group at least at the end by condensation reaction Transistor manufacturing method. Forming a source and a drain electrode on the insulating substrate; Forming a magnetic molecular assembly layer on the source and drain electrodes; Forming an organic semiconductor layer on the magnetic molecular assembly layer; Forming an insulating layer to cover the organic semiconductor layer; And Forming a gate electrode at a predetermined position on the insulating layer to correspond to the source and drain electrodes; The thin film, characterized in that the magnetic molecular assembly layer forming step is carried out by applying a silane-based compound having a primary amino group and an aromatic compound having an electron attracting group and a condensation reaction group at least at the end by condensation reaction Transistor manufacturing method. 13. The method of claim 11 or 12, wherein forming the source and drain electrodes further comprises oxidizing source and drain electrode surfaces. The method of claim 11 or 12, wherein the magnetic molecular assembly layer forming step is to apply a silane-based compound having a primary amino group at least at the end, and then apply the silane-based compound applied to a region other than the top of the source and drain electrodes. And removing the thin film transistor. The method of claim 11 or 12, wherein the magnetic molecular assembly layer forming step comprises applying a silane-based compound having a primary amino group and an aromatic compound having an electron attraction and a condensation reaction group at least at a terminal thereof, and then source and drain electrodes. And removing a condensation reaction product of the silane compound and the aromatic compound applied to an area except the upper portion. A flat panel display device comprising the thin film transistor according to any one of claims 1 to 10, and a pixel electrode connected to a source electrode or a drain electrode of the thin film transistor.

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