KR100735978B1 - Method of manufacturing organic light emitting device - Google Patents

Abstract

A method for manufacturing an organic light emitting device is provided to reduce an ion damage generated in a surface of a pixel electrode according to a high deposition temperature of an inorganic insulating material by forming a sensitive film on the pixel electrode and an inorganic insulating layer on the sensitive film, and forming a pixel separation film. A method for manufacturing an organic light emitting device includes the steps of: forming a thin film transistor(120) having gate, source and drain electrodes on a substrate(100); forming a planarization film(130) on an upper plane of the thin film transistor(120), and forming a pixel electrode(140) which is connected to the thin film transistor(120) on the planarization film(130); forming a sensitive pattern on at least a part of the pixel electrode(140); forming a pixel separation film(150') by depositing and selectively patterning an inorganic insulating layer of a predetermined thickness on an upper part of the result material; and forming an organic light emitting layer(160) and an electrode(170) on the upper part of the result material.

Description

Manufacturing method of organic electroluminescent device {METHOD OF MANUFACTURING ORGANIC LIGHT EMITTING DEVICE}

1 is a cross-sectional view for explaining an organic electroluminescent device according to an embodiment of the present invention.

2A to 2I are cross-sectional views illustrating a method of manufacturing an organic electroluminescent device according to an embodiment of the present invention.

*** Explanation of symbols on main parts of drawing ***

100: substrate, 110: blocking film,

120: thin film transistor, 121: active pattern,

122: gate insulating film, 123: gate electrode,

124: interlayer insulating film, 124a and 124b: contact hole,

125: source electrode, 126: drain electrode,

130: planarization film, 135: contact hole,

140: pixel electrode, 150: inorganic insulating layer,

150 ': pixel separator, 155: opening,

160: organic electroluminescent layer, 170: electrode,

P1 and P2: first and second photoresist pattern

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an organic electroluminescent device, and more particularly, when a inorganic insulating material is deposited as a pixel separation layer for separation between pixel electrodes, a photoresist pattern is formed on a pixel electrode, By forming an inorganic insulating layer and then selectively patterning it to form a pixel separation layer, ion damage and haze occurring on the surface of the pixel electrode can be minimized, and a high brightness and high efficiency organic electric field can be minimized. The present invention relates to a method of manufacturing an organic electroluminescent device to enable a light emitting device.

In general, an organic light emitting device (OLED) injects electrons and holes into the light emitting layer from a cathode electrode and an anode electrode, respectively, to be injected. It is a device that emits light when an exciton in which electrons and holes are combined falls from an excited state to a ground state.

Due to this principle, unlike the conventional thin film liquid crystal display device, since a separate light source is not required, there is an advantage in that the volume and weight of the device can be reduced.

In addition, the organic electroluminescent device (OLED) exhibits high quality panel characteristics (low power, high brightness, high reaction rate, low weight). Due to these characteristics, organic light emitting diodes (OLEDs) are used in most consumer devices such as mobile communication terminals, car navigation systems (CNS), personal digital assistants (PDAs), camcorders, and palm PCs. It is considered a powerful next-generation display that can be used in electronic applications.

In addition, since the manufacturing process is simple, there is an advantage that can reduce the production cost much more than a conventional liquid crystal display (LCD).

The organic light emitting diode OLED is a passive matrix (PM) method and an active matrix (AM) method according to a method of driving N × M pixels arranged in a matrix form. Divided into.

The Passive Matrix Organic Light Emitting Device (PMOLED) has a simple structure and a simple manufacturing method. However, it is difficult to increase the power consumption and the large area of the display device. There is a disadvantage of deterioration.

On the other hand, the active matrix organic light emitting device (AMOLED) is less power consumption than the passive matrix method is suitable for large area implementation, there is an advantage that can provide high luminous efficiency and high image quality. .

A conventional method of manufacturing an active matrix organic electroluminescent device (AMOLED) is disclosed in Korean Patent Laid-Open Publication No. 2003-69434 (active matrix organic light emitting display device and its manufacturing method). A thin film transistor (TFT) including a gate insulating film, a gate electrode, an interlayer insulating film, a source, and a drain electrode is formed, and a planarization film for planarization of pixel regions on the front surface of the substrate including the thin film transistor (TFT) and the thin film transistor thereon. The pixel electrode is formed to be connected to.

Subsequently, a pixel separation layer for separation between the pixel electrodes is formed on the front surface of the resultant so that a part of the pixel electrode is exposed, and an organic electroluminescent layer and a metal electrode are sequentially stacked on the exposed pixel electrode, thereby active matrix organic electroluminescence. Complete the device.

However, when the pixel isolation layer is formed of an organic insulating material (for example, an organic resin, etc.), a high exposure time (or exposure amount) is required due to the high viscosity and bonding energy of the organic insulating material, which causes exposure equipment. It has a problem of reducing the lamp life of the product, and also due to the compatibility problem with the mass production photoresist (PR) when using the mass production equipment, it cannot proceed simultaneously with the mass production model, which increases the process tact time. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object of the present invention is to form a photoresist pattern on a pixel electrode when a inorganic insulating material is deposited as a pixel separation film for separation between pixel electrodes, and to have a predetermined thickness thereon. By forming an inorganic insulating film and then patterning it selectively to form a pixel separation layer, ion damage and haze occurring on the surface of the pixel electrode can be minimized, and high brightness and high efficiency organic electroluminescence The present invention provides a method of manufacturing an organic electroluminescent device that can not only implement the device but also effectively reduce the process tact time and cost.

In order to achieve the above object, an aspect of the present invention, (a) forming a thin film transistor including a gate electrode, a source and a drain electrode on the substrate; (b) forming a planarization film on the entire upper surface of the thin film transistor, and then forming a pixel electrode connected to the thin film transistor on the planarization film; (c) forming a photoresist pattern on at least a portion of the pixel electrode; (d) depositing and selectively patterning an inorganic insulating layer having a predetermined thickness on top of the resultant to form a pixel isolation layer; And (e) to provide an organic electroluminescent device manufacturing method comprising the step of forming an organic electroluminescent layer and an electrode on top of the result.

Here, the step (d) may include: (d-1) depositing an inorganic insulating layer having a predetermined thickness on the resultant; (d-2) forming a photoresist pattern on at least a portion of the inorganic insulating layer and etching the inorganic insulating layer on the pixel electrode using the photoresist pattern as a mask; And (d-3) removing the remaining photoresist pattern to form a pixel separation layer having an opening that exposes a portion of the pixel electrode.

Preferably, in the step (d), the inorganic insulating layer is deposited to a thickness of about 1400 kPa to 1600 kPa.

Preferably, in the step (d), the pixel separation layer is formed of a silicon nitride layer (SiNx) or a silicon oxide layer (SiO ₂ ).

Preferably, the organic electroluminescent layer is formed by sequentially stacking a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer and an electron injection layer.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, embodiments of the present invention illustrated below may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

1 is a cross-sectional view illustrating an organic light emitting device (OLED) according to an exemplary embodiment of the present invention, but an active matrix organic light emitting diode (AMOLED) is implemented as an example, but is not limited thereto. Passive matrix organic light emitting diode (PMOLED) may be implemented.

Referring to FIG. 1, a blocking layer 110 made of silicon oxide is formed on a substrate 100 such as, for example, glass, quartz, or sapphire.

Although the blocking film 110 may be omitted, it is preferable to use it to prevent various impurities in the substrate 100 from penetrating into the silicon film during the subsequent crystallization of the amorphous silicon film.

A plurality of thin film transistors including an active pattern 121, a gate insulating layer 122, a gate electrode 123, an interlayer insulating layer 124, and source and drain electrodes 125 and 126 on the blocking layer 110. TFTs 120 are formed to be arranged at regular intervals.

The planarization layer 130 for planarization of the pixel region is formed on the entire surface of the substrate 100 including the thin film transistor 120. The pixel electrode 140 connected to one of the source and drain electrodes 125 and 126, for example, the drain electrode 126, is formed on the planarization layer 130 through the contact hole 135.

Here, the planarization layer 130 is preferably configured to include an organic insulating material such as, for example, an acrylic organic compound, polyimide, BCB (Benzo Cyclo Butene) or PFCB, but is not limited thereto. For example, it may include an inorganic insulating material such as silicon nitride.

The pixel electrode 140 is formed of a transparent conductive film that transmits light, such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO). It is provided as an anode electrode of an organic electroluminescent element.

A pixel isolation layer 150 ′ having an opening 155 exposing a portion of the pixel electrode 140 is formed on the planarization layer 130 including the pixel electrode 140, and holes are formed on the opening 155. Hole Injection Layer (HIL), Hole Transfer Layer (HTL), Emitting Layer (EML), Electron Transfer Layer (ETL), and Electron Injection Layer (EIL) The organic electroluminescent layer 160 stacked thereon is formed.

Here, the pixel isolation layer 150 ′ is preferably made of an inorganic insulating material such as silicon nitride layer (SiNx) or silicon oxide layer (SiO ₂ ).

Finally, the electrode 170 for the back emission is formed on the organic electroluminescent layer 160 as a cathode of the organic electroluminescent device, thereby completing the organic electroluminescent device according to an embodiment of the present invention.

Hereinafter, a method of manufacturing an organic electroluminescent device according to an embodiment of the present invention having the above-described structure will be described.

2A to 2I are cross-sectional views illustrating a method of manufacturing an organic electroluminescent device according to an embodiment of the present invention.

Referring to FIG. 2A, a barrier film 110 having a predetermined thickness is formed on a substrate 100 such as, for example, glass, quartz, or sapphire, and a low pressure chemical vapor deposition method is performed on the barrier film 110, for example, an amorphous silicon film. Chemical layer deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD) or the like to deposit a thickness of about 300 kPa to 700 kPa (preferably about 500 kPa) to form an active layer (not shown). ), And then, for example, laser annealing is performed to crystallize the active layer into polycrystalline silicon.

Subsequently, the polysilicon active layer is patterned by, for example, a photolithography process to form the active pattern 121 in the thin film transistor region in the unit pixel.

At this time, the formation of the blocking film 110 may be omitted, but it is preferable to use it to prevent various impurities in the substrate 100 from penetrating into the silicon film during the subsequent crystallization of the amorphous silicon film.

Referring to FIG. 2B, the gate insulating layer 122 is formed by depositing silicon oxide on the blocking layer 110 and the active pattern 121 in a thickness of about 1000 GPa to 2000 GPa by plasma chemical vapor deposition (PECVD).

Thereafter, for example, aluminum-neodymium (AlNd) is deposited on the gate insulating film 122 to a thickness of about 2000 kPa to 4000 kPa (preferably, about 3000 kPa) by sputtering, and then a photolithography process is performed. The gate layer is patterned to form a gate electrode 123.

In this case, source and drain regions (not shown) of the thin film transistor 120 to be described later are formed on both surfaces of the active pattern 121 by performing impurity ion implantation using a photomask used in the patterning process of the gate film described above. do.

Referring to FIG. 2C, after performing laser annealing or furnace annealing to activate doped ions in the source and drain regions and to cure damage to the silicon layer, silicon nitride is applied to the entire upper surface of the resultant. The interlayer insulating film 124 is formed by depositing at a thickness of about 7000 kPa to 9000 kPa (preferably about 8000 kPa).

Subsequently, the interlayer insulating layer 124 is etched by, for example, a photolithography process to form contact holes 124a and 124b exposing portions of the source and drain regions, respectively.

Next, a conductive layer such as molybdenum tungsten (MoW) or aluminum-neodymium (AlNd) is deposited on the interlayer insulating layer 124 and the contact holes 124a and 124b to a thickness of about 3000 kPa to 6000 kPa. The conductive layer is patterned by a photolithography process to form source and drain electrodes 125 and 126 in contact with the source and drain regions, respectively.

Through the above-described processes, the thin film transistor 120 including the active pattern 121, the gate insulating layer 122, the gate electrode 123, the source and drain electrodes 125 and 126 is formed.

Referring to FIG. 2D, planarization is performed on the interlayer insulating layer 124 including the thin film transistor 120, for example, by depositing an organic or inorganic insulating material to a thickness of about 2000 μs to 3000 μs to planarize the pixel electrode 140 to be described later. The film 130 is formed.

Subsequently, the planarization layer 130 is etched by, for example, a photolithography process to form a contact hole 135 exposing one of the source and drain electrodes 125 and 126, for example, the drain electrode 126.

In addition, a transparent conductive film such as indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) is deposited on the planarization layer 130 and the contact hole 135, and then patterned by a photolithography process. The pixel electrode 140 connected to the drain electrode 126 of the thin film transistor 120 is formed through the 135. The pixel electrode 140 is provided as an anode electrode of the organic electroluminescent device.

Referring to FIG. 2E, in order to suppress ion damage and haze on the surface of the pixel electrode 140 when the pixel isolation layer 150 ′ (see FIG. 2H) is formed to separate the pixel electrodes 140. After coating the photoresist (PR) (not shown) having a predetermined thickness on the entire upper surface of the planarization layer 130 and the pixel electrode 140, the pixel electrode ( The first photoresist pattern P1 is formed on the 140.

Referring to FIG. 2F, an inorganic insulating layer 150 made of, for example, silicon nitride film (SiNx), silicon oxide film (SiO ₂ ), or the like is formed on the entire upper surface of the resultant, about 1400 kPa to 1600 kPa (preferably, about 1500 kPa). Deposit to a certain thickness of degree.

Referring to FIG. 2G, after the photoresist film PR (not shown) having a predetermined thickness is coated on the entire upper surface of the resultant product, the second photoresist pattern P2 for forming the pixel isolation layer 150 ′ (see FIG. 2H) is formed. To form.

Referring to FIG. 2H, after the inorganic insulating layer 150 is etched using the formed second photoresist pattern P2 as an etching mask, the remaining first and second photoresist patterns P1 and P2 are removed. A pixel isolation layer 150 ′ having an opening 155 exposing a portion of the pixel electrode 140 is formed.

Referring to FIG. 2I, a hole injection layer HIL, a hole transport layer HTL, an emission layer EML, an electron transport layer ETL, and an electron injection layer EIL are sequentially stacked on a region including the opening 155. After the formed organic electroluminescent layer 160 is formed, an electrode 170 provided as a cathode electrode of the organic electroluminescent device having a predetermined thickness is formed on the entire upper surface of the resultant, thereby providing an embodiment of the present invention. The manufacturing method of the organic electroluminescent device according to this is completed.

Although preferred embodiments of the method of manufacturing the organic electroluminescent device according to the present invention have been described above, the present invention is not limited thereto, and various modifications are made within the scope of the claims and the detailed description of the invention and the accompanying drawings. It is possible to carry out by this and this also belongs to the present invention.

According to the manufacturing method of the organic electroluminescent device of the present invention as described above, when the inorganic insulating material is deposited by the pixel separation film for separation between the pixel electrodes, a photoresist pattern is formed on the pixel electrode, By forming an inorganic insulating layer and then selectively patterning it to form a pixel separation layer, ion damage occurring on the surface of the pixel electrode due to the high deposition temperature (about 300 ° C. or more) of the inorganic insulating material can be effectively reduced. When the pixel electrode is an ITO electrode, for example, when the pixel electrode is an ITO electrode, a phenomenon in which the surface of the pixel electrode is blurred by hydrogen gas can be minimized, and organic electroluminescence of high brightness and high efficiency can be minimized. Not only can the device be implemented, but it can also effectively reduce the process tact time and cost.

Claims (5)

(a) forming a thin film transistor including a gate electrode, a source and a drain electrode on the substrate; (b) forming a planarization film on the entire upper surface of the thin film transistor, and then forming a pixel electrode connected to the thin film transistor on the planarization film; (c) forming a photoresist pattern on at least a portion of the pixel electrode; (d) depositing and selectively patterning an inorganic insulating layer having a predetermined thickness on top of the resultant to form a pixel isolation layer; And (e) forming an organic electroluminescent layer and an electrode on top of the resultant. The method of claim 1, wherein step (d) (d-1) depositing an inorganic insulating layer having a predetermined thickness on the resultant; (d-2) forming a photoresist pattern on at least a portion of the inorganic insulating layer and etching the inorganic insulating layer on the pixel electrode using the photoresist pattern as a mask; And (d-3) forming a pixel separator having an opening exposing a part of the pixel electrode by removing the remaining photoresist pattern. The method of claim 1, wherein in the step (d), the inorganic insulating layer is deposited to a thickness of about 1400 kPa to 1600 kPa. The method of claim 1, wherein in the step (d), the pixel separation layer is formed of a silicon nitride layer (SiNx) or a silicon oxide layer (SiO ₂ ). The method of claim 1, wherein the organic electroluminescent layer is formed by sequentially laminating a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer.

Images