KR101949574B1 - Organic light emitting transistor and manufacturing method thereof - Google Patents

Abstract

The organic light emitting transistor according to the present invention includes a substrate 10, an insulating layer 20 formed on a top surface of the substrate 10, and a pentancene compound A hole transport layer 30 formed on the insulating layer 20; 4- (dicyanomethylene) -2-methyllin-6- (p-dimethylaminostyryl) -4-dicyanomethylene- (8-hydroxyquinoline) aluminum (Alq ₃ ), doped with tris (4H-pyran, -4H-pyran, DCM) and includes a light emitting layer 40 formed on the hole transport layer .

Description

TECHNICAL FIELD [0001] The present invention relates to an organic light emitting transistor and a method of manufacturing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to an organic light emitting transistor and a method of manufacturing the same, and more particularly, to an organic light emitting transistor driven at a low voltage and having excellent electric field mobility in air and a method of manufacturing the same.

Organic semiconductor electronic devices are one of the most advanced IT technologies that can provide application concepts completely different from existing inorganic semiconductor based devices. Of organic semiconductors, organic light-emitting diodes (OLEDs) have gained popularity as high-quality displays such as those used in small-screen and TV screens of mobile phone main windows and various mobile devices.

In general, a flat panel display panel is a device having a flat front panel using a characteristic of emitting visible light. When a strong voltage is applied between two electrodes, a gas discharge occurs between the electrodes, and ultraviolet rays generated at this time strike the phosphor A plasma display panel (PDP) using a light emitting phenomenon, a cathode (cathode) formed by a flat cathode, and a FED (electroluminescence display) or a filament , A grid Grid), electrons are accelerated to reach an anode, and a current is flowed through a VFD (vacuum fluorescent display) that displays information by emitting light by impinging on a patterned phosphor, a fluorescent or phosphorescent organic thin film OLED (Organic Light Emitting Display Panel), which is a light emitting type in which electrons and holes combine in an organic layer to generate light, A liquid crystal display (LCD) that displays information using a principle that a liquid crystal acts as a shutter and transmits or blocks light according to switching of a voltage as a display applied to a display device, ).

On the other hand, as a driving method for driving the organic EL element, an active matrix type field effect transistor (FET) using a thin film transistor (TFT: Thin Film Transistor) is effective in terms of operation speed and power consumption . On the other hand, semiconductor materials constituting thin film transistors have been studied for inorganic semiconductor materials such as silicon semiconductors and compound semiconductors, and recently organic thin film transistors (organic TFTs) using organic semiconductor materials have also been actively studied . The organic semiconductor material is expected as a next-generation semiconductor material, but has a problem of lower charge mobility and higher resistance than an inorganic semiconductor material.

On the other hand, as for the field-effect transistor, it is possible to shorten the channel width of the transistor in a vertical FET structure (vertical induction transistor (SIT) with vertical FET structure) It is possible to realize a high-speed response and a large power, and it is difficult to be affected by an interface. Therefore, recently, an organic light emitting transistor having such an SIT structure and an organic EL element structure combined with each other has been developed, utilizing the advantages of the electrostatic induction type transistor (SIT) as disclosed in the following prior art documents.

In particular, organic light-emitting transistors (OLEDs) and OLEDs (OLEDs) and OLEDs (OTFTs) are commonly used in OLEDs. In general, OLEDs employ a lateral conduction channel structure, , It is useful both in the basic research of organic electronic materials and devices and in the development of technical applications. OLEFETs can provide an excellent evaluation system for studying physical processes such as charge carrier injection, transfer and electroluminescence in organic semiconductors intuitively because the luminescence phenomenon is expressed in the transverse channel structure. Since OLEFET is a highly integrated device capable of controlling the luminescence phenomenon, it can be also applied to the development of an active matrix full-color electroluminescent display or the development of a variable type organic laser device. However, the OLETET has a problem that the electric field mobility in the air and the stability of the device are poor.

Accordingly, there is an urgent need for a solution to the problem of OLETET.

KR 10-2008-0082656 A

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the conventional art described above. One aspect of the present invention is to provide a method for forming a hole transport layer and a light emitting layer by using a specific compound on an insulating layer, And has an excellent balance of electron mobility.

An organic light emitting transistor according to the present invention includes a substrate; An insulating layer formed on an upper surface of the substrate; A hole transport layer formed on the insulating layer, the hole transport layer including a pentancene compound; 4- (dicyanomethylene) -2-methyllin-6- (p-dimethylaminostyryl) -4-dicyanomethylene- (8-hydroxyquinoline) aluminum (Alq ₃ ) doped with tris (4-pyrrolidin-4-yl) -4H-pyran, DCM) and a light emitting layer formed on the hole transport layer.

Further, in the organic light emitting transistor according to the present invention, the doping concentration of the DCM is 0.5 to 1.0 mol%.

Further, in the organic light emitting transistor according to the present invention, the thickness of the hole transporting layer is 490 to 510 ANGSTROM.

Further, in the organic light emitting transistor according to the present invention, the thickness of the light emitting layer is 490 to 510 ANGSTROM.

Further, in the organic light emitting transistor according to the present invention, a hole injection electrode made of gold (Au) and disposed on the light emitting layer; And an electron injection electrode disposed on the light emitting layer so as to face each other with a predetermined gap from the hole injection electrode.

Further, in the organic light emitting transistor according to the present invention, the electron injection electrode is an alloy of lithium (Li) and aluminum (Al).

In addition, in the organic light emitting transistor according to the present invention, the electron injection electrode is formed by sequentially stacking lithium fluoride (LiF) and aluminum (Al).

Further, in the organic light emitting transistor according to the present invention, the width of the channel formed between the hole injection electrode and the electron injection electrode is 10 mm, and the length of the channel is 200 탆.

Meanwhile, a method of manufacturing an organic light emitting transistor according to the present invention comprises the steps of: A) preparing a substrate; B) forming an insulating layer on an upper surface of the substrate; C) inserting the substrate into a cluster beam deposition chamber; D) depositing a pentane compound in the first crucible, vaporizing it by heating, and supplying it into the cluster beam deposition chamber to deposit a hole transport layer on the insulating layer; E) A compound of tris (8-hydroxyquinoline) aluminum, Alq ₃ ) was placed in the second crucible, and 4- (dicyanomethylene) -2-methyllin 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran, DCM) Depositing a light emitting layer on the hole transporting layer by supplying each vapor into the cluster beam deposition chamber by vaporizing by heating; And F) forming a hole injecting electrode and an electron injecting electrode on the light emitting layer, respectively.

Also, in the organic light emitting transistor according to the present invention, the hole injection electrode is formed by depositing gold (Au), and the electron injection electrode is formed by depositing an alloy of lithium (Li) and aluminum (Al).

In addition, in the organic light emitting transistor according to the present invention, the temperature of the first crucible is 220 to 250 ° C, and the temperature of the second crucible is 330 to 350 ° C.

In addition, in the organic light emitting transistor according to the present invention, the deposition rate of the hole transport layer is 0.5 to 1.0 Å / s, and the deposition rate of the light emitting layer is 0.1 to 0.3 Å / s.

Further, in the organic light emitting transistor according to the present invention, each of the first crucible, the second crucible, and the third crucible has a nozzle for supplying the vaporized compound into the cluster beam deposition chamber, and the diameter Is 0.5 to 1.5 mm.

In the organic light emitting transistor according to the present invention, the first crucible, the second crucible, and the third crucible are heated by a voltage application method, and a voltage of 6 to 8 V is applied to the first crucible, And a voltage of 10 to 12 V is applied to the second crucible and the third crucible, respectively.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to that, terms and words used in the present specification and claims should not be construed in a conventional and dictionary sense, and the inventor may properly define the concept of the term in order to best explain its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to the present invention, the electric field mobility in the air is improved by using a dopant material having a high luminous efficiency and an asymmetric electrode, and depositing a predetermined compound on the light emitting layer and the hole transporting layer.

Further, the stability of the device is improved, and the present invention can provide a motive for developing a driving circuit more easily in the future.

1 is a cross-sectional view of an organic light emitting transistor according to an embodiment of the present invention.
2 is a plan view of an organic light emitting transistor according to an embodiment of the present invention.
3 is a perspective view illustrating the operation principle of the organic light emitting transistor according to the embodiment of the present invention.
4 is a cross-sectional view of a vaporizing apparatus for manufacturing an organic light emitting transistor according to an embodiment of the present invention.
5 is an image of a light emission of the organic light emitting transistor according to the embodiment of the present invention taken by a CCD camera.
6 is a graph showing the photoluminescence characteristics of the organic light emitting transistor according to the embodiment of the present invention.
7 is a graph showing the output characteristics of the organic light emitting transistor according to the embodiment of the present invention.
8 is a graph showing the transfer characteristics of the organic light emitting transistor according to the embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The objectives, specific advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. Also, the terms " first ", " second ", and the like are used to distinguish one element from another element, and the element is not limited thereto. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description of the present invention, detailed description of related arts which may unnecessarily obscure the gist of the present invention will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of an organic light emitting transistor according to an embodiment of the present invention. FIG. 2 is a plan view of an organic light emitting transistor according to an embodiment of the present invention. Fig.

1 and 2, an organic light emitting transistor according to an embodiment of the present invention includes a substrate 10, an insulating layer 20 formed on a top surface of the substrate 10, and a pentancene compound A hole transport layer 30 formed on the insulating layer 20; 4- (dicyanomethylene) -2-methyllin-6- (p-dimethylaminostyryl) -4-dicyanomethylene- (8-hydroxyquinoline) aluminum (Alq ₃ ), doped with tris (4H-pyran, -4H-pyran, DCM) and includes a light emitting layer 40 formed on the hole transport layer .

The organic light emitting transistor according to the present invention is an organic electronic device capable of controlling a luminescent phenomenon and playing an important role in the next generation active type organic light emitting display industry. The organic electronic device includes a substrate 10, an insulating layer 20, a hole transport layer 30 ), And a light emitting layer (40).

Here, the substrate 10 may be an n-type silicon substrate. At this time, the substrate 10 is used as an input electrode to apply a gate voltage. However, the substrate 10 is not necessarily limited to the n-type silicon substrate, but may be a plastic substrate. Such a plastic substrate may be formed of a material selected from the group consisting of polyethersulphone (PES), polyacrylate, polyetherimide (PEI), polyethylene naphthalate (PEN), polyethyeleneterephthalate (PET) (PPS), polyarylate (PAR), polyimide (PI), polycarbonate (PC), cellulose triacetate (TAC) and cellulose acetate propinonate , CAP). Meanwhile, the organic light emitting transistor according to the present invention may further include a gate electrode (not shown) disposed on the lower surface of the substrate 10 to apply a gate voltage when the substrate 10 is a plastic substrate.

The insulating layer 20 is a layer formed on the upper surface of the substrate 10. Here, the insulating layer 20 may be made of SiO ₂ , but is not limited thereto. On the insulating layer 20, a hole transport layer 30 is disposed.

The hole transport layer 30 is a layer formed on the insulating layer 20, and is formed by depositing a pentancene compound. At this time, the thickness of the hole transport layer 30 may be 490 to 510 Å. However, the thickness is not necessarily limited thereto.

A light emitting layer 40 is formed on the hole transport layer 30 where the light emitting layer 40 is formed of 4- (dicyanomethylene) -2-methyllin-6- (p -dimethyllaminostyryl) A mixture of tris (8-hydroxyquinoline) aluminum, Alq ₃ ) and pyridine (4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H- . That is, the light emitting layer 40 is formed of Alq ₃ doped with DCM, and the doping concentration of the DCM may be 0.5 to 1.0 mol%. The thickness of the light emitting layer 40 may be in the range of 490 to 510 Å. However, the thickness of the light emitting layer 40 may vary depending on the doping concentration, process conditions, and the like.

The organic light emitting transistor according to the present invention has a structure in which the substrate 10, the insulating layer 20, the hole transporting layer 30, and the light emitting layer 40 are sequentially stacked, And an electron injection electrode (60).

The hole injecting electrode 50 and the electron injecting electrode 60 are arranged on the light emitting layer 40 so as to face each other with a predetermined gap therebetween. Here, the material used as the hole injection electrode 50 is preferably Au. Since gold work function is large, hole injection into the organic material layer is considerably easy. However, the hole injecting material is not necessarily limited to gold, and vanadium, chromium, copper, and zinc may be used.

As the material used for the electron injection electrode 60, a material having a small work function is preferably used so that electron injection into the organic material layer can be smoothly performed. Here, the material of the electron injecting electrode 60 that can be used for the insulating layer 20, the hole transporting layer 30, and the light emitting layer 40 of the above-described material includes an alloy of lithium (Li) and aluminum (Al) ) Or lithium fluoride (LiF), and aluminum (Al), which are sequentially stacked. In the case of the LiF / Al electron injection electrode 60, the thickness of LiF is formed to be 1 nm or less.

That is, the hole injecting electrode 50 and the electron injecting electrode 60 according to the present invention are formed of asymmetric electrodes made of different materials.

Meanwhile, the hole injection electrode 50 and the electron injection electrode 60 are spaced apart from each other by a predetermined distance, and a channel C is formed therebetween. At this time, the optimum channel width W is 10 mm, The optimum channel length L may be 20 [mu] m. However, the width and length of the channel are not necessarily limited thereto.

The emission principle of the organic light emitting transistor according to the present invention is as follows.

Referring to FIG. 3, when 0 to -90 V is applied to the gate electrode, and -90 V is applied to the electron injection electrode, charges are generated in the gate and holes are accumulated in the hole transport layer. The electrons in the Alq ₃ are induced by the laminated holes, and holes and electrons recombine in the DCM layer to generate light.

As a result, the organic light emitting transistor according to the present invention improves the electric field mobility in the air by using the asymmetric electrode and the dopant material excellent in luminous efficiency and depositing the predetermined compound on the light emitting layer and the hole transporting layer, The stability is improved.

Hereinafter, a method of manufacturing an organic light emitting transistor according to the present invention will be described. At this time, the above-described parts of the organic transistor according to the present invention are not described or simply described.

A method of manufacturing an organic light emitting transistor according to an embodiment of the present invention includes the steps of: A) preparing a substrate; B) forming an insulating layer on an upper surface of the substrate, C) inserting a substrate into the cluster beam deposition chamber, D) depositing a pentancene compound in the first crucible and heating it to vaporize it and supplying it to the interior of the cluster beam deposition chamber to deposit a hole transport layer on the insulating layer; E) depositing a tris (8 (Tris (8-hydroxyquinoline) aluminum, Alq ₃ ) compound was placed in a third crucible, and 4- (dicyanomethylene) -2-methyllinine-6- (p -dimethyllaminos (Dicyanomethylene-2-methyl-6- (p-dimethylaminostyryl) -4H-pyran, DCM) were added and then vaporized by heating each to form cluster- The light emitting layer is deposited on the hole transporting layer And F) forming a hole injecting electrode and an electron injecting electrode on the light emitting layer, respectively.

An organic light emitting transistor according to the present invention is manufactured by the following method.

FIG. 4 is a cross-sectional view of a vaporizing apparatus for manufacturing an organic light emitting transistor according to an embodiment of the present invention. Referring to FIG. 4, a vacuum deposition apparatus used in accordance with the present invention will be described. At least one crucible 102 or 103 having a heating wire as a heating means is disposed on the lower side of the support base 101 and a crucible 102 And 103 are formed with a lid having nozzles so that the crucibles 102 and 103 have an airtight shape except for the nozzle at the top and the materials to be deposited are respectively placed in the crucibles. In addition, the thickness monitor 100 installed for measuring the thickness of the deposited thin film, which indicates the deposition rate and thickness of the deposited thin film in units of Å / s and k Å, respectively, do. The shutter 110 is disposed between the substrate and the crucibles 102 and 103 so that the shutter 110 can be opened and closed from the outside. The shutter 110 is initially closed to prevent deposition of undefined impurities, When it reaches it, it is provided so that it can be rotated and opened from the outside.

The method of manufacturing the organic light emitting transistor of the present invention using the vacuum vapor deposition equipment will be described in more detail. In step A), a substrate is prepared. Here, a gate electrode (or an input electrode) can be formed on the lower surface of the substrate, and the method is not particularly limited as long as it is a commonly used method in the art. Here, the substrate has been described above, and a detailed description thereof will be omitted.

Next, in step B), an insulating layer is formed on the upper surface of the substrate, and the material forming the insulating layer may be SiO ₂ . However, the insulating layer is not necessarily limited to SiO ₂ .

Once the insulating layer is formed, as step C), the substrate is inserted into the cluster beam deposition chamber. Inside the cluster beam deposition chamber, as described above, at least one crucible is disposed, each crucible having a nozzle. Here, the material of the crucible is not particularly limited as long as it is a material which does not adsorb or react with the compounds when heating compounds such as pentacene, Alq ₃ and DCM described later. However, Low graphite is preferred. In addition, although the shape of the crucible is not particularly limited as long as the crucible can be provided with a lid having a nozzle on the top thereof, it is preferable to form a thin film by spin coating. Meanwhile. The nozzle is a passage through which the compounds sublimate and is discharged toward the substrate, and the diameter thereof may preferably be 0.5 to 1.5 mm. If the diameter of the nozzle provided in the crucible is less than 0.5 mm, clustered vapor particles described later are difficult to pass through the nozzle, and when the diameter exceeds 1.5 mm, the cluster molecules become too large, It is not preferable because it is difficult to form. Therefore, the kinetic energy generated when passing through a nozzle having a diameter of 0.5 to 1.5 mm can supply energy necessary for migration in order to form a uniform thin film. Therefore, it is advantageous in that it can be deposited at room temperature without being heated in the deposition step by the moving energy.

When the substrate is inserted into the chamber, the hole transport layer is deposited according to the step D). To this end, a pentacene compound is placed in a first crucible having a first nozzle, and the compound is vaporized by heating by a voltage application method. Then, the vaporized compound is supplied into the cluster beam deposition chamber through the first nozzle, whereby a hole transport layer is formed on the substrate. At this time, a voltage of 6.0 to 8.0 V can be applied to the crucible. If a voltage of less than 6.0 V is applied, the organic material may not sublimate and the deposition may not be performed smoothly. If the voltage is higher than 9.0 V, the deposition rate may not be controlled. In addition, the temperature of the first crucible may preferably be 220 to 250 ° C. If the internal temperature of the first crucible is lower than 220 캜, the compound is difficult to vaporize, and it is difficult to form an organic thin film because it can not supply sufficient energy required for thermal polymerization in a flat substrate. The chemical composition of the material forming the thin film may be a modified form and the roughness of the surface becomes poor.

The deposition process will be described in more detail. The cluster that has sublimed and passed through the nozzle of the crucible advances to the inner side of the vacuum chamber and collides with the lower portion of the substrate. The collided clusters break the weak intermolecular bonding force and become originally sublimed organic particles, moving to the surrounding vacancies and bonding with the substrate. On the other hand, the surfactant can be laminated on the surface of the substrate before the clusters are deposited. When the pentacene compound is used, the thickness of the pentacene compound may range from 490 to 510 Å. The deposition rate of the clusters is preferably 0.5 to 1.0 Å / S. When the deposition rate is less than 0.5 Å / S, It is difficult to form the organic thin film properly because it is too slow, and when it exceeds 1.0 ANGSTROM, the roughness of the produced organic thin film may be poor.

On the other hand, it is preferable not to heat the substrate at the time of cluster beam deposition, more preferably, the vaporized cluster can be deposited at room temperature of 20 to 30 DEG C to form an organic film. If the substrate is heated, the production cost required for heating is increased, and it is difficult to establish the temperature uniformity of the entire substrate as a process condition in accordance with the increase in size.

When the pentacene compound is heated in a vacuum state, it is sublimated into a gas by a phase change, and sublimated compound particles flow inside the first crucible. The flowing particles pass through the nozzle formed in the upper part of the crucible. Since the particles pass through the small hole of the nozzle, only the particles moving in the upward direction, that is, the particles having the kinetic energy in one direction pass through the nozzle . Therefore, the particles vaporized inside the crucible flow inside the crucible and hit each other, forming a cluster with a weak intermolecular attraction, and only the clusters having an upwardly directed direction have a uniform and constant kinetic energy, passes through the nozzle in the form of a beam and proceeds toward the inner upper side of the vacuum chamber. The clusters having upward directionality and uniform and constant kinetic energy at the same time collide with the lower part of the substrate disposed on the inner upper side of the vacuum chamber and the weak intermolecular attractive force of the cluster is broken by the collision, The thickness of the thin film which is eventually formed becomes uniform, and the crystallinity is excellent.

On the other hand, according to the conventional physical vapor deposition (PVD) method or the OMBD method, the organic molecules to be deposited have specific orientation and do not move in a vacuum chamber, but a plate-shaped or bowl- A phenomenon of direct evaporation to a surrounding environment in a vacuum state occurs. This is different from clusters in the cluster beam deposition according to the present invention, in which organic molecules are clustered due to weak attraction. That is, organic molecules having kinetic energy of a wide distribution size with various directions of orientation in a vacuum state are sublimated. Therefore, particles with a wide range of kinetic energy are deposited in many directions from many directions, so that the surface of the substrate has a rough island shape. Therefore, the surface of the organic molecules to be deposited becomes coarse, and the crystalline is lowered, thereby reducing the electric field mobility.

Next, in Step E), the Alq ₃ compound is placed inside the second crucible, the DCM compound is placed in the third crucible, and then the second and third crucibles are placed inside the cluster beam deposition chamber. At this time, each compound is heated and vaporized by a voltage application method, so that each vaporized compound is supplied into the cluster beam deposition chamber through the second and third nozzles to form a light emitting layer on the substrate. Here, the doping concentration of the mixture for preparing the optimal light emitting layer using photoluminescence spectra equipment is derived, and the optimal doping concentration is preferably 0.5 to 1.0 mol%. The range of PL corresponding to 0.5 to 1.0 mol% is 575 to 590 nm. For this purpose, a voltage of 10.0 to 12.0 V can be applied to the second crucible. If the voltage is lower than 10.0 V, the organic material may not sublimate and the deposition may not be performed smoothly. If the voltage is higher than 12.0 V, the deposition rate may not be controlled and the doping concentration of DCM may exceed 1.0 mol% May cause problems.

On the other hand, the temperature of the second crucible may preferably be 330 to 350 ° C. If the internal temperature of the second crucible is less than 330 ° C., the compound is not easily vaporized and the organic thin film is difficult to form because it can not supply sufficient energy required for thermal polymerization in a flat substrate, DCM is not doped smoothly due to insufficient temperature. If the temperature exceeds 350 ° C., the chemical composition of the thin film-forming material may be modified and the roughness of the surface may become poor. Due to the high internal temperature of the third crucible, the concentration of DCM may exceed 1.0 mol% It is not preferable.

In addition, the surfactant can be deposited on the surface of the substrate before depositing the clusters. When the compound is used, the thickness may be 490 to 510 Å. When the deposition rate is less than 0.1 A / S, the deposition rate of the thin film is too slow, so that the organic thin film is difficult to be formed properly, and the deposition rate of more than 0.3 A / S The roughness of the produced organic thin film may be poor.

When the light emitting layer is formed as described above, a hole injecting electrode and an electron injecting electrode are formed as step F). Here, gold (Au) is used as the hole injection electrode material, Li: Al or LiF / Al is used as the electron injection electrode material, and a shadow mask having a channel thickness of about 10 mm and a channel length of about 200 탆 is used And then the respective electrodes are deposited by vacuum evaporation. At this time, LiF is formed to be 1 nm or less.

5 is an image of a light emission of the organic light emitting transistor according to the embodiment of the present invention taken by a CCD camera. As shown in FIG. 5, the organic light emitting transistor manufactured by the above-described method exhibited luminescence characteristics as intended when a predetermined voltage was applied.

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

≪ Example 1 >

1- (1) Gate electrode formation

A gate electrode having a thickness of 2000 angstroms was formed on the bottom of the cleaned n-type silicon substrate using aluminum (Al).

1- (2) Hole transport layer deposition

The vacuum degree in the vacuum chamber was maintained at an average of 1 × 10 ^-5 Torr by using a 10-inch diffusion pump with a baffle, and graphite having a cover having a nozzle with a diameter of 1 mm formed thereon ) Material was placed on the inner lower side of the vacuum chamber and the n-type silicon substrate was placed on the inner upper side of the vacuum chamber with the SiO ₂ laminated side down. At this time, the distance between the n-type silicon substrate and the first crucible was 190 mm. Next, pentacene was injected into the first crucible, and an electron transport layer having a thickness of 490-510 Å was deposited at a heating temperature of 220-250 ° C. and a deposition rate of 0.5-1.0 Å / sec. At this time, the temperature of the substrate temperature was maintained at 20 占 폚.

1- (3) Deposition of a light emitting layer

Alq ₃ and DCM were respectively injected into the second crucible and the third crucible, and a voltage of 490 to 510 Å was applied to the light emitting layer at a heating temperature of 330 to 350 ° C. and a deposition rate of 0.1 to 0.3 Å / sec. Respectively.

1- (4) Formation of hole injection electrode and electron injection electrode

Next, a hole injection electrode made of gold (Au) and an electron injection electrode made of Li: Al were formed by a vacuum evaporation method using a shadow mask having a channel width of 10 mm and a channel length of 200 탆 with a film thickness of 500 Å, An electrode and an electron injection electrode were deposited to produce an organic light emitting transistor.

≪ Example 2 >

In the step 1- (4) of Example 1, an electron injection electrode was deposited using LiF / Al to fabricate an organic light emitting transistor.

≪ Comparative Example 1 &

In the above embodiment, a light emitting layer is formed of Alq ₃ , and a hole injection electrode and an electron injection electrode are deposited by gold (Au) material to manufacture an organic light emitting transistor.

≪ Comparative Example 2 &

In this embodiment, the hole injecting electrode and the electron injecting electrode are both made of gold (Au) material to manufacture an organic light emitting transistor.

≪ Comparative Example 3 &

In the above embodiment, the light emitting layer was formed of Alq ₃ , the hole injection electrode was formed of gold (Au), and the electron injection electrode was formed of Li: Al to form an organic light emitting transistor.

<Experimental Example>

The properties of the organic luminescence transistors of Examples 1 to 2 and Comparative Examples 1 to 3 were evaluated as follows.

6 is a graph showing the photoluminescence characteristics of the organic light emitting transistor according to the embodiment of the present invention. 6, when DCM is not doped and Alq ₃ It can be seen that the luminescent characteristics do not appear when the luminescent layer alone is formed and the luminescent characteristics are exhibited only in the case of the luminescent layer doped with DCM.

In addition, the organic luminescence transistor manufactured in Examples 1 and 2 is shown in Figs. 7 and 8 by measuring electrical characteristics in air.

FIG. 7 is a graph showing the output characteristics of the organic light emitting transistor according to the embodiment of the present invention. In FIG. 7A, b), respectively. 8 is a graph showing the transfer characteristics of the organic light emitting transistor according to the embodiment of the present invention. In the case of Embodiment 1, FIG. 8 (a) 8 (b), respectively. On the other hand, the gate sweep curve, that is, the electric field mobility (μ _FET , cm ² / Vs), the current flickering ratio (I _{on / off} ), and the threshold voltage (V _T , V) 1 &gt;.

&Quot; (1) &quot;

However, the <Equation 1 from <L is the width (㎛) and an I _DS between the drain and the source channel is the current flowing between the source and drain electrode W is the length between the source and drain electrodes channel C _i is the dielectric layer And the unit is nF / cm &lt; ² &gt; to be. V _GS is the voltage (in volts) between the source and gate electrodes and V _T is the threshold voltage.

The following Table 1 shows the properties of the organic light emitting transistors prepared according to Examples 1 to 2 and Comparative Examples 1 to 3

μ _eff ^{h, avg} ± σ
(Cm2 / Vs) I _{on / off} Light emission Comparative Example 1 0.16 ± 0.06 1E + 06 X Comparative Example 2 0.16 + 0.03 5E + 05 X Comparative Example 3 0.12 + 0.09 4E + 05 X Example 1 0.17 ± 0.06 6E + 05 ○ Example 2 0.20 ± 0.11 2E + 06 ○

As a result, in the organic light emitting transistor according to the first and second embodiments of the present invention, light emission occurred, whereas in the organic light emitting transistor manufactured according to the comparative example, there was no light emission. As a result, the pentacene compound was used as the hole transporting layer, and DCM-doped Alq ₃ It can be seen that when the compound is used as a light emitting layer, the luminescent characteristics are exerted only when the hole injecting electrode and the electron injecting electrode are formed of asymmetric electrodes.

In general, according to the organic light emitting transistor of the present invention, by using an asymmetric electrode and a dopant material excellent in luminous efficiency and depositing a predetermined compound on the light emitting layer and the hole transporting layer, the electric field mobility in the air and the stability of the device And furthermore, the present invention can provide a motive for developing a driving circuit more easily in the future.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention. It is obvious that the modification or improvement is possible.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: substrate 20: insulating layer
30: hole transport layer 40: light emitting layer
50: Hole injection electrode 60: Electron injection electrode

Claims (14)

Board;
An insulating layer formed on an upper surface of the substrate;
A hole transport layer formed on the insulating layer, the hole transport layer including a pentancene compound; And
4- (dicyanomethylene) -2-methyllin-6- (p-dimethylaminostyryl) -4-dicyanomethylene- And a light-emitting layer formed on the hole transport layer, wherein the light-emitting layer comprises tris (8-hydroxyquinoline) aluminum (Alq ₃ ) doped with 4H-pyran, DCM,
A hole injecting electrode disposed on the light emitting layer and made of gold (Au); And
And an electron injection electrode disposed on the light emitting layer so as to face each other with a predetermined gap from the hole injection electrode,
The electron injection electrode is an alloy of lithium (Li) and aluminum (Al)
And the doping concentration of the DCM is 0.5 to 1.0 mol%.
delete The method according to claim 1,
And the thickness of the hole transport layer is 490 to 510 ANGSTROM.
The method according to claim 1,
Wherein the thickness of the light emitting layer is 490 to 510 ANGSTROM.
delete delete delete The method according to claim 1,
A width of the channel formed between the hole injection electrode and the electron injection electrode is 10 mm, and a length of the channel is 200 m.
A) preparing a substrate;
B) forming an insulating layer on an upper surface of the substrate;
C) inserting the substrate into a cluster beam deposition chamber;
D) depositing a pentane compound in the first crucible, vaporizing it by heating, and supplying it into the cluster beam deposition chamber to deposit a hole transport layer on the insulating layer;
E) A compound of tris (8-hydroxyquinoline) aluminum, Alq ₃ ) was placed in the second crucible, and 4- (dicyanomethylene) -2-methyllin 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran, DCM) Depositing a light emitting layer on the hole transporting layer by supplying each vapor into the cluster beam deposition chamber by vaporizing by heating; And
F) forming a hole injection electrode and an electron injection electrode on the light emitting layer,
The hole injection electrode is formed by depositing gold (Au)
The electron injection electrode is formed by vapor-depositing an alloy of lithium (Li) and aluminum (Al)
Wherein the doping concentration of the DCM is 0.5 to 1.0 mol%.
delete The method of claim 9,
Wherein the temperature of the first crucible is 220 to 250 占 폚 and the temperature of the second crucible is 330 to 350 占 폚.
The method of claim 9,
Wherein the deposition rate of the hole transport layer is 0.5 to 1.0 Å / s, and the deposition rate of the light emitting layer is 0.1 to 0.3 Å / s.
The method of claim 9,
Wherein each of the first crucible, the second crucible, and the third crucible has a nozzle for supplying a vaporized compound into the cluster beam deposition chamber, wherein the nozzle has a diameter of 0.5 to 1.5 mm .
The method of claim 9,
Each of the first crucible, the second crucible, and the third crucible is heated by a voltage application method,
Wherein a voltage of 6 to 8 V is applied to the first crucible and a voltage of 10 to 12 V is applied to the second crucible and the third crucible, respectively.

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