KR20060066829A - Organic electro-luminescent device and method for fabricating the same - Google Patents

Abstract

In the present invention, a mixture of materials forming the cathode electrode and the electron injection layer by chemical bonding between the cathode electrode and the electron injection layer formed thereon is mixed. The present invention provides an organic light emitting display device, which is formed such that a mixed layer of silicon is formed to lower the size of the electron injection barrier to improve electron injection ability and to lower driving voltage.

DOD, inverted structure, cathode, electron injection layer, organic light emitting device

Description

Organic electroluminescent device and method of manufacturing the same {Organic electro-luminescent device and method for fabricating the same}             

1 is a view showing a basic pixel structure of a general active matrix organic electroluminescent device.

2 is a schematic cross-sectional view of a conventional organic light emitting device.

3 is a cross-sectional view schematically illustrating an organic light emitting display device in which a conventional array device and an organic light emitting diode are configured on different substrates, respectively.

4 is a cross-sectional view schematically showing an organic light emitting device according to the present invention with respect to one subpixel region.

5A and 5B are schematic cross-sectional views of a second substrate for an organic light emitting device in which an inverted structure organic light emitting diode according to the present invention is formed.

<Explanation of symbols for main parts of drawing>

201: first substrate 205: buffer layer

210: semiconductor layer 210a: active layer

210b: p-type ohmic contact layer 213: gate insulating film                 

225; Interlayer insulating films 227 and 229: first and second semiconductor layer contact holes

233 data wiring 235 source electrode

237: drain electrode 240: protective layer

243: drain contact hole 250: connection electrode

261: second substrate 265: first electrode (cathode)

270: electron injection layer (mixed layer) 275: electron transport layer

278: (red, green, blue) organic light emitting layer 280: hole transport layer

283 hole injection layer 287 second electrode (anode)

290: electrical connection pattern

Tr: Driving Thin Film Transistor

The present invention relates to an organic electroluminescent device, and more particularly, to a cathode electrode structure for improving driving voltage and efficiency and a method of forming the same.

Recently, the demand for flat panel display devices with less space is increasing due to the increase in the size of display devices. Among the flat panel display devices, the organic light emitting devices are attracting attention.                         

The organic light emitting display device, which is one of the flat panel displays (FPDs), is self-luminous and has a superior viewing angle and contrast compared to the liquid crystal display. In addition, it is advantageous in terms of power consumption, and it can be used as a small-sized flat panel display device because it can be driven by current, has a fast response speed, and is solid, which is strong against external shocks, has a wide range of operating temperatures, and is particularly inexpensive in terms of manufacturing cost. have.

The organic light emitting diode is generally composed of an organic light emitting layer between a first electrode, a second electrode, and the first and second electrodes, wherein the first and second electrodes are anodes for supplying holes, respectively. ) And a cathode for supplying electrons, and when holes and electrons are supplied from the first and second electrodes to the organic light emitting layer, the holes and the electrons are combined to form a pair. Excitons fall from the excited state to the ground state, emitting energy in the form of light and emitting light.

Hereinafter, the basic structure and operation characteristics of the active matrix organic light emitting display device will be described in detail with reference to the accompanying drawings.

1 is a view showing a basic pixel structure of a general active matrix organic electroluminescent device.

As shown, the gate line GL is formed in the first direction, the data line DL and the power supply line are formed in the second direction crossing the first direction and spaced apart from each other. , PSL is formed to define one subpixel area SP.

A switching TFT (SwT), which is an addressing element, is formed at an intersection point of the gate line GL and the data line DL. The switching thin film transistor SwT and the power supply wiring PSL are formed. ) is associated with and the storage capacitor (C _ST) is formed, connected with the storage capacitor (C _ST) and the power supply lines (PSL), the current source element (current source element) of the driving TFT (DrT) is formed In addition, the organic light emitting diode E is connected to the driving thin film transistor DrT.

At this time, when the organic light emitting diode (E) supplies current to the organic light emitting material in a forward direction, P (P) between an anode electrode which is a hole providing layer and a cathode electrode which is an electron providing layer is provided. Electrons and holes move through the positive-N (negative) junction and recombine with each other, so they have less energy than when the electrons and holes are apart. In this case, it uses the principle of emitting light due to the difference in energy generated.

FIG. 2 is a schematic cross-sectional view of a conventional organic light emitting diode, and is illustrated based on one pixel area including red, green, and blue subpixels.

As shown in the drawing, the first and second substrates 10 and 30 are disposed to face each other, and the edge portions of the first and second substrates 10 and 30 are sealed by a seal pattern 40. In this case, a driving thin film transistor DrT is formed for each subpixel SP on the transparent substrate 11 of the first substrate 10, and is connected to the driving thin film transistor DrT to form an organic light emitting diode. The first electrode 12, which is one of the constituent elements, is formed, and each of the subpixels SP has independent red, green, and blue colors on the first electrode 12 connected to the driving thin film transistor DrT. An organic light emitting layer 14 including a light emitting material is formed, and a second electrode 16 is formed on the organic light emitting layer 14. In this case, the first and second electrodes 12 and 16 serve to apply an electric field to the organic light emitting layer 14.

The second electrode 16 and the second substrate 30 are spaced apart from each other by the seal pattern 40 described above, and although not shown in the drawing, the inner surface of the second substrate 30 may be formed from the outside. A moisture absorbent for blocking water that may be introduced and a semipermeable tape for adhesion between the moisture absorbent and the second substrate 30 are included.

The organic light emitting device as described above is characterized in that the array element and the organic light emitting diode is composed of a stacked structure on the same substrate.

However, in the fabrication of the organic light emitting device having the structure in which the above-described array device and the organic light emitting diode are stacked on the same substrate, bonding of a substrate on which the array device and the organic light emitting diode is formed and a separate encapsulation substrate is performed. In this case, since the product of the yield of the array device and the yield of the organic light emitting diode determines the yield of the organic light emitting device, the organic field corresponding to the latter process in the conventional organic light emitting device structure. The overall process yield is greatly limited by the light emitting diode process.                         

Therefore, to solve this problem, an organic light emitting diode has been proposed, in which an array element and an organic light emitting diode are formed on different substrates, and the two substrates are electrically bonded to each other.

3 is a schematic cross-sectional view of an organic light emitting display device, in which a conventional array device and an organic light emitting diode are formed on different substrates, respectively.

As illustrated, the first and second substrates 110 and 130 are disposed to face each other, and the edge portions of the first and second substrates 110 and 130 are sealed by the seal pattern 140. An array element 120 is formed for each subpixel SP on the first substrate 110, and each subpixel SP of the first substrate 110 is disposed below the second substrate 130. In response to this, an organic light emitting diode E is formed. In this case, the organic light emitting diode E may serve as a first electrode 132 used as a common electrode, an organic light emitting layer 134 under the first electrode 132, and a lower portion under the organic light emitting layer 134. The second electrode 136 is formed independently for each pixel SP. In this case, the array element 120 formed for each subpixel SP on the first substrate 110 includes a driving thin film transistor DrT and a connection electrode 112 connected to the driving thin film transistor DrT. have.

In addition, the second electrode 136 and the array element 120 are electrically connected in a section between the second electrode 136 formed on the second substrate 130 and the connection electrode 112 formed on the first substrate 110. An electrical connection pattern 114 is formed to conduct.

In this case, when the organic light emitting diode E including the organic light emitting layer 314 is described in detail, the first electrode 132 may be a cathode and the second electrode 136 may be an anode. In the case of an electrode structure, that is, an organic light emitting device having an inverted structure, the first electrode 132 is formed of a metal material having a low work function, for example, aluminum (Al). The second electrode 136 is formed of a conductive material having a work function higher than that of the first electrode 132, for example, indium-tin-oxide (ITO), and the organic electroluminescent layer 134 exhibits luminous efficiency. The electron injection layer 134a, the electron transporting layer 134b, the emission layer 134c, and the hole transporting layer are sequentially lowered to the lower portion of the first electrode. 134d, hole injection layer 134e in order Form a layered structure. In this case, the organic light emitting layer has a structure in which light emitting materials for red, green, and blue are sequentially disposed for each subpixel SP.

However, the aforementioned dual panel type inverted structure organic light emitting device has a problem of high driving voltage and low luminous efficiency.

This is because the multi-layered organic electroluminescent layer is formed by vacuum evaporation, but when it is not inverted type, indium-tin-oxide (ITO) having a high work function that forms an anode on a substrate. And finally forming an organic electroluminescent layer of an electron injection layer by a vacuum deposition method from a hole injection layer, and finally forming aluminum (Al) to form a cathode Is formed at a relatively high temperature, when forming the cathode electrode of aluminum, the chemical bonding with the electron injection layer in contact with the cathode electrode due to the high temperature is smoothly achieved. Does not occur, but in the inverted structure organic electroluminescent device as described above, anod forming a cathode on a substrate The aluminum (Al) layer is formed by forming an aluminum (Al) layer before the electron injection layer, and then forming an organic electroluminescent layer and an ITO layer including the electron injection layer. In contrast, chemical bonding between the electron injection layer and the cathode electrode, which are vacuum deposited at a low temperature, does not occur, resulting in a large electron injection barrier between the two material layers, thereby lowering the electron injection ability, thereby increasing the driving voltage. The problem that light emission efficiency falls is generated.

It is an object of the present invention to form a cathode of a multilayer thin film structure so that chemical bonding with an electron injection layer formed thereon can occur smoothly.

In addition, another object of the present invention is to provide an organic light emitting display device having a low driving voltage and improved luminous efficiency by lowering an electron injection barrier size between the two material layers.

According to an aspect of the present invention, there is provided an organic light emitting display device including: a first substrate having a gate line and a data line intersecting to define a subpixel, and having an array element for each subpixel; A second substrate corresponding to and configured to the first substrate; A first electrode formed of a metal material having a work function value of 4 eV or less on an inner surface of the second substrate; An electron injection layer made of a metal material and a compound material of an inorganic material under the first electrode; A multilayer organic electroluminescent layer including an organic emission layer under the electron injection layer; A second electrode formed under the organic electroluminescent layer with a conductive material having a work function greater than the metal material; And an electrical connection pattern contacting the second electrode and the array element at the same time.

The organic light emitting layer includes an electron transporting layer, the organic light emitting layer, a hole transporting layer, and a hole injection layer, wherein the organic light emitting layer is a subpixel. Very red, green, and blue are repeated sequentially.

In addition, the metal material is aluminum (Al), the conductive material is indium tin oxide (ITO), the inorganic material is preferably one selected from LiF, Li ₂ O, SiO ₂ .

In addition, the mixed layer is characterized in that aluminum (Al), and any one of LiF, Li ₂ O, SiO ₂ and mixed by vacuum deposition.

The array device may further include at least one p-type switching thin film transistor and a driving thin film transistor including a p-doped polysilicon layer, and further include a connection electrode in contact with a drain electrode of the driving thin film transistor. The electrical connection pattern is in contact with the connection electrode.

In addition, any one of the first and second substrates may further include a seal pattern bordering the substrate.

According to a first aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, the method including: forming an array element at a crossing point on a gate line and a data line crossing each other on the first substrate; Forming an electrical connection pattern on the first substrate in contact with the array element; Forming a first electrode on the second substrate using a metal material having a work function value of 4 eV or less; Forming an electron injection layer, which is a compound of the metal material and the inorganic material, to a first thickness by vacuum depositing the metal material and the inorganic material as the source on the first electrode; Forming a multilayer organic electroluminescent layer over the electron injection layer; Forming a second electrode on the organic electroluminescent layer using a conductive material having a work function greater than the metal material; And sealing the seal pattern on one of the first and second substrates, contacting one end of the electrical connection pattern with the second electrode, and bonding the two substrates together.

At this time, the first thickness is preferably 100 kPa to 150 kPa.

According to a second aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, the method including: forming an array element at a crossing point on a gate line and a data line crossing each other on a first substrate; Forming an electrical connection pattern on the first substrate in contact with the array element; Vacuum depositing a metal having a work function value of 4 eV or less on the second substrate to form a first electrode of a first thickness; Forming an inorganic material layer having a second thickness by vacuum depositing the inorganic material over the first electrode; Vacuum depositing the metal material on the inorganic material layer to a third thickness to form an electron injection layer in which the metal material is diffused into the inorganic material layer to chemically bond the inorganic material and the metal material; Forming a multilayer organic electroluminescent layer over the electron injection layer; Forming a second electrode on the organic electroluminescent layer using a conductive material having a work function greater than the metal material; And sealing the seal pattern on one of the first and second substrates, contacting one end of the electrical connection pattern with the second electrode, and bonding the two substrates together.

In this case, the first thickness is 1000 kPa to 2000 kPa, the second thickness is 5 kPa to 10 kPa, and the third thickness is preferably 80 kPa to 100 kPa.

In the first and second features, the metal material is aluminum (Al), the conductive material is indium tin oxide (ITO), and the inorganic material is one selected from LiF, Li ₂ O, and SiO ₂ . desirable.

In the first and second aspects, the forming of the multilayer organic light emitting layer may include forming an electron transporting layer; Forming a red, green, and blue organic light emitting layer that is sequentially repeated for each subpixel on the electron transporting layer; Forming a hole transporting layer on the organic light emitting layer; And forming a hole injection layer on the hole transporting layer.

In the first and second aspects, the forming of the array element at the intersection point between the gate line and the data line and the interconnection on the first substrate may include forming a polysilicon pattern on the substrate; Forming a gate insulating film on an entire surface of the polysilicon pattern; Forming a gate electrode on the gate insulating layer to correspond to the polysilicon, including a gate wiring; Performing p + doping on the entire surface of the substrate; Forming an interlayer insulating film over the gate electrode and the gate wiring; Forming a source line and a drain electrode on the interlayer insulating layer, the source and drain electrodes respectively contacting the polysilicon pattern, and a data line crossing the gate line, wherein the passivation layer is formed over the source and drain electrodes and the data line. And forming a connection electrode in contact with the drain electrode on the passivation layer. In this case, the forming of the polysilicon pattern may include forming an amorphous silicon pattern on the first substrate; Crystallizing the amorphous silicon pattern into a polysilicon pattern.

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

The dual panel type inverted structure organic light emitting display device requires a higher driving voltage than a general organic light emitting display device. Nevertheless, the reason for using the dual panel type inverted structure organic light emitting diode is because of the dual panel type, which can improve the manufacturing yield and at the same time it is used in connection with the p type polysilicon thin film transistor. to be.

A thin film transistor having another amorphous silicon (a-Si) or n-type polysilicon as a semiconductor layer is connected to an organic light emitting diode having a general structure to form an organic light emitting device.

However, in general, a thin film transistor using amorphous silicon (a-Si) as a semiconductor layer is inferior in mobility and characteristics compared to a thin film transistor using polysilicon as a semiconductor layer, and thus is difficult to use for driving. This is because the n-type polysilicon thin film transistor including a manufacturing process is more complicated than the thin film transistor using the p-type polysilicon, resulting in an increase in manufacturing cost.

Therefore, a dual panel type inverted structure organic electroluminescent device using a p-type polysilicon thin film transistor having excellent characteristics such as mobility required by the driving thin film transistor and having no complicated manufacturing as a driving thin film transistor is used. Although the driving voltage is high, it is possible to provide an excellent organic light emitting device in many aspects such as stable driving side and deterioration side.

4 is a schematic cross-sectional view of an organic light emitting diode according to an exemplary embodiment of the present invention.

 As illustrated, the organic light emitting diode according to the present invention includes a first substrate 201 having an array element including a driving thin film transistor Tr and first and second electrodes corresponding to the first substrate 201. A second substrate 261 comprising an organic electroluminescent light emitting diode (E) composed of (265, 287) and an organic electroluminescent layer (OE) interposed between the two electrodes (265, 287), and the first, 2 substrates 201 and 261 More specifically, the first substrate 201 is provided with one electrode 237 of the driving thin film transistor Tr provided for each subpixel SP and a lower portion of the second substrate 261. An electrical connection pattern 290 for electrically connecting the second electrode 287 and a seal pattern are included in the edge portions of the first and second substrates 201 and 261 although not shown in the drawing.

The cross-sectional structure will be described in more detail. Although not shown in the drawing on the first substrate 201, gate and data lines (not shown) 233 and the two lines (not shown) that cross each other to define a subpixel SP are included. An array element including a driving thin film transistor Tr and a switching thin film transistor (not shown) formed at the intersection of 233 is formed. In this case, the array element is a p-type thin film transistor including a p-type semiconductor layer of polysilicon doped with p-type impurities.

A passivation layer 240 is formed on the p-type driving thin film transistor Tr, and a connection electrode 250 connected to the drain electrode 237 of the p-type driving thin film transistor is disposed on the passivation layer 240. It is formed for each pixel SP.

In the second substrate 261, a first electrode 265 is formed below the substrate to form a cathode on a front surface of a metal material having a relatively low work function value, for example, aluminum (Al). An inorganic material such as lithium fluoride (LiF), lithium oxide (Li ₂ O), or silicon oxide (SiO ₂ ) is formed below the first electrode 265 and the first electrode 265 is formed. Aluminum (Al), which is a metal material, is chemically bonded by a specific manufacturing method, that is, an electron injection layer (electron), characterized in that the material formed with the first electrode 265 is mixed with the inorganic material. An injection layer 270 is formed, and an electron transporting layer 275 and an organic light emitting layer 278 of red, green, and blue below the electron injection layer 270. Hole transporting layer 280 and hole column Layer (hole injection layer) (283) are formed sequentially. An electron injection layer 270, an electron transporting layer 275, an organic light emitting layer 278, a hole transporting layer 280 forming the organic electroluminescent layer OE, The hole injection layers 283 are all formed by vacuum deposition.

Next, a conductive material having a high work function value, for example, indium-tin oxide (ITO), is deposited under the hole injection layer 283 to have a higher work function value than the first electrode. A second electrode 287, which is an anode electrode, is formed.

In addition, the first substrate 201 and the second substrate 261 are in contact with the second electrode 287 and the connection electrode 250 connected to the drain electrode 237 of the driving thin film transistor Tr at the same time. An electrical connection pattern 290 is formed for each subpixel SP.

In the organic light emitting device having the above-described structure, the most characteristic of the present invention is an electron injection layer for contacting the cathode and the cathode of the organic light emitting diode and improving the electron injection efficiency. (electron injection layer) structure and its formation method.

When the cathode is formed of aluminum (Al), there is a problem that the electron injection ability is inferior due to the material properties of the aluminum (Al) itself, so as to compensate for this, an electron transport layer between the organic emission layer 278 and the cathode electrode. (electron transporting layer) and electron injection layer (electron injection layer) are formed, the cathode (cathode electrode) made of aluminum (Al) having a work function lower than 4eV due to the structural characteristics, for example, LiF, Li ₂ Formed before an electron injection layer made of an inorganic material such as O and SiO ₂ , and then selected from the above-described inorganic materials on the cathode electrode of aluminum (Al). When the electron injection layer is formed, chemical bonding between the two layers, for example, aluminum (Al) and LiF, is not performed, thus forming only a cathode and an emission layer of aluminum (Al). Even if the electron injection ability is improved rather than the structure, the degree of improvement is very weak, and there is a problem of increasing the driving voltage applied to the cathode electrode and the anode electrode.

In order to solve this problem, in the present invention, a method of forming an organic electroluminescent layer including an anode (first electrode) and an electron injection layer on the cathode is illustrated in FIGS. 5A and 5B, hereinafter, the cathode and the electron injection layer It will be described in detail how to form.                     

As shown in FIG. 5A, aluminum (Al), which is a metal material having a work function value of 4 eV or less, is vacuum deposited on the substrate 261 to be formed to have a thickness of about 1000 GPa to 2000 GPa. A first electrode 265 is formed on the entire surface, and aluminum (Al) is used as a source in addition to an inorganic material selected from LiF, Li ₂ O, and SiO ₂ in a vacuum chamber over the first electrode 265 made of aluminum (Al). Further, the two materials are vacuum deposited at the same time to form the electron injection layer 270. At this time, the temperature in the vacuum deposition chamber proceeds according to the deposition temperature of aluminum (Al), such as a mixture of the inorganic material and aluminum (Al) at the interface with the first electrode 265, for example, LiF-Al layer, etc. It is characterized in that to form a thickness of 100Å to 150Å. In this case, compared to the electron injection barrier between the electron injection layer formed of only inorganic materials such as LiF, Li ₂ O, SiO _2, and the like, and the first electrode 265 made of aluminum (Al), The electron injection barrier is lowered by the generation of the mixture electron injection layer 270 having intermediate characteristics, thereby improving the electron injection ability. Therefore, the driving voltage can be lowered by improving the electron injection ability.

Subsequently, as illustrated in FIG. 5B, vacuum deposition is performed on the mixture-type electron injection layer 270 to form an electron transporting layer 275, an organic light emitting layer 278, and holes. A hole transporting layer 280 and a hole injection layer 283 are sequentially formed, and a work function value over the hole injection layer 283 is 4eV or more. By depositing ITO, which is a highly transparent conductive material, a second electrode 287 forming an anode is formed to complete a second substrate 261 having an organic light emitting diode having an inverted structure.

A method of forming a second substrate having an organic light emitting diode having a lower electron injection barrier between another cathode electrode and an electron injection layer is shown in FIGS. 6A to 6C. The first electrode 365 as a cathode is formed by vacuum depositing aluminum (Al) on the entire surface, and among inorganic materials such as LiF, Li ₂ O, SiO _2, and the like, on the first electrode 365. By vacuum depositing one, an inorganic material layer 367 having a thickness of preferably 5 kPa to 10 kPa is formed, and the same material that forms the cathode on the water layer 367, that is, aluminum (Al) is formed. Vacuum deposition to a thickness of 80 kPa to 100 kPa to form an aluminum layer 368. In this case, when the aluminum (Al) layer is naturally formed, chemical bonding occurs at an interface between the aluminum (Al) and the inorganic material layer below the aluminum (Al) layer, and finally, the upper aluminum (Al) into the thinly formed inorganic material layer. ) Is permeated to form an electron transporting layer 370 made of a mixture of inorganic material and aluminum (Al), thereby lowering the electron injection barrier. Thereafter, an electron transporting layer 375, an organic light emitting layer 378, a hole transporting layer 380, and a hole injection layer 383 are sequentially formed by vacuum deposition. Inverted by forming a second electrode 387 forming an anode by depositing ITO, a transparent conductive material having a work function value of 4 eV or more, above the hole injection layer 383. The second substrate 361 including the (inverted) structure organic light emitting diode can be completed.

In the fabrication of the second substrate having the organic light emitting diode having the aforementioned electron injection barrier lowered, the organic light emitting layer and the second electrode emitting red, green, and blue light, which are formed separately for each subpixel instead of front deposition, are vacuumed. By using the shadow mask during deposition, it can be formed so as to separate each subpixel as if patterned by photolithography.

Next, a method of manufacturing a first substrate for an organic light emitting device having an array device including a driving thin film transistor using p-type polysilicon will be described with reference to FIG. 4.

First, an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is deposited on a substrate to form a buffer layer 205, and a polysilicon semiconductor layer 210 is formed on the buffer layer 205. Form.

In this case, in the process of forming the semiconductor layer 210 using the polysilicon, after depositing amorphous silicon (a-Si) on the buffer layer 205, and patterning it, the poly by heat treatment or laser irradiation By crystallizing with silicon, the semiconductor layer 210 of polysilicon can be formed.

In this case, the crystallization process may be performed after forming the amorphous silicon on the entire surface, or may be performed after patterning the amorphous silicon layer as described above.

Next, on the substrate 201 on which the semiconductor layer 210 of polysilicon is formed, an inorganic insulating material is deposited on the entire surface to form a gate insulating film 213, and then a metal material is deposited on the gate insulating film 213. By patterning, the gate electrode 217 is formed at the center of the semiconductor layer 210 of polysilicon. In this case, a gate wiring (not shown) and a power supply wiring (not shown) are formed together with the same material as the gate electrode 217 on the front surface of the substrate 201.

In this case, the gate electrode 217 and the gate wiring (not shown) are made of aluminum (Al) or aluminum alloy (AlNd) as a lower layer, and chemical corrosion resistance such as molybdenum (Mo), nickel (Ni), and tungsten (W). It may be formed of a double metal layer having this strong metal as an upper layer or formed of a single layer.

Next, a region corresponding to the gate electrode 217 is ion-implanted with p-type impurities by using the gate electrode 217 as a mask on the substrate 201 where the gate electrode 217 and the gate wiring (not shown) are formed. The p-type ohmic contact layer 210b is formed by doping other semiconductor layers. At this time, the region not doped with the p-type impurity forms the active layer 210a.

Next, an inorganic insulating material is deposited on the entire surface of the gate electrode 217 and the gate wiring (not shown) to form an interlayer insulating film 225, and the p-type ohmic contact layer 210b is patterned by patterning the interlayer insulating film 225. The first and second semiconductor layer contact holes 227 and 229 are formed, and the first and second semiconductor layer contact holes 227 and 229 are formed by depositing and patterning a metal material on the interlayer insulating layer 225. Contact with the p-type ohmic contact layer 210b and the source and drain electrodes 235 and 237 spaced apart from each other, and the data line connected to the source electrode 235 and crossing the gate line (not shown). 233 is formed. In this case, the semiconductor layer 210, the gate insulating layer 213, the gate electrode 217, the interlayer insulating layer 225, and the source and drain electrodes 235 and 237 constitute an array element, more precisely, a switching thin film transistor (not shown). And the driving thin film transistor Tr.

Next, a drain that exposes the drain electrode 237 by depositing or applying an inorganic or organic insulating material on the entire surface of the substrate 261 on which the source and drain electrodes 235 and 237 and the data line 233 are formed, and patterning the same. A protective layer 240 having a contact hole 243 is formed.

Thereafter, a connection electrode 250 is formed on the passivation layer 240 to contact the drain electrode 237 through the drain contact hole 243, and a metal material is deposited and patterned on the connection electrode 250. Alternatively, the first substrate 201 for the organic light emitting diode according to the present invention may be formed by forming a spacer and forming an electrical connection pattern 290 in which a metal material is plated on the surface of the spacer so as to be conductive with the connection electrode 250. To complete).

Next, as described above, the two substrates 201 and 261 include a first substrate 201 including an array element and a second substrate 261 on which an inverted structure organic light emitting diode E is formed. A seal pattern (not shown) is formed on one of the substrates along an edge, and the driving thin film transistor Tr is formed for each sub-pixel SP on the first substrate 201 in an atmosphere of vacuum or inert gas. The organic connection field is formed by contacting the first and second substrates 201 and 261 by bringing the electrical connection pattern 290 formed in contact with the drain electrode 237 into contact with the second electrode 287 of the second substrate 261. Complete the light emitting device.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

The organic electroluminescent device according to the present invention as described above has a substrate in which a failure occurs even if a failure occurs in any of the steps of fabricating an array element and manufacturing an organic light emitting diode by configuring the organic light emitting diode and the array element on different substrates. Since the two substrates of the good product is removed and the product defect rate is lowered, there is an effect of improving the production yield.

In addition, by providing a manufacturing method for forming a mixture of the materials forming the cathode electrode and the electron injection layer between the cathode electrode and the electron injection layer to be mixed with each other. By lowering the electron injection barrier between the layers to improve the electron injection ability, there is an effect of lowering the driving voltage and improving luminous efficiency.

Claims (25)

A first substrate having a gate line and a data line intersecting to define a subpixel, and having an array element for each subpixel; A second substrate corresponding to and configured to the first substrate; A first electrode formed of a metal material having a work function value of 4 eV or less on an inner surface of the second substrate; An electron injection layer made of a metal material and a compound material of an inorganic material under the first electrode; A multilayer organic electroluminescent layer including an organic emission layer under the electron injection layer; A second electrode formed under the organic electroluminescent layer with a conductive material having a work function greater than the metal material; Electrical connection pattern in contact with the second electrode and the array element at the same time Organic electroluminescent device comprising a. The method of claim 1, The organic electroluminescent layer is An organic light emitting device comprising an electron transporting layer, the organic light emitting layer, a hole transporting layer, and a hole injection layer. The method of claim 1, The metal material is an aluminum electroluminescent device. The method of claim 1, The conductive material is an indium tin oxide (ITO) organic light emitting device. The method of claim 1, The inorganic material is an organic electroluminescent device which is one selected from LiF, Li ₂ O, SiO ₂ . The method of claim 1, The mixed layer is an organic electroluminescent device mixed with aluminum (Al), any one of LiF, Li ₂ O, SiO ₂ by vacuum deposition. The method of claim 1, The array device includes an organic light emitting device comprising at least one p-type switching thin film transistor and a driving thin film transistor each comprising a p-doped polysilicon layer. The method of claim 7, wherein And a connection electrode in contact with the drain electrode of the driving thin film transistor. The method of claim 8, The electrical connection pattern is an organic EL device in contact with the connection electrode. The method of claim 2, The organic light emitting device of the organic light emitting layer is a red, green, blue sequentially repeated for each sub-pixel. The method of claim 1, The organic light emitting device of claim 1, wherein one of the first and second substrates is further provided with a seal pattern bordering the substrate. Forming an array element at a crossing point on the gate line and the data line crossing each other on the first substrate; Forming an electrical connection pattern on the first substrate in contact with the array element; Forming a first electrode on the second substrate using a metal material having a work function value of 4 eV or less; Forming an electron injection layer, which is a compound of the metal material and the inorganic material, on the first electrode by vacuum deposition using a metal material and an inorganic material as a source to a first thickness; Forming a multilayer organic electroluminescent layer over the electron injection layer; Forming a second electrode on the organic electroluminescent layer using a conductive material having a work function greater than the metal material; A step of bordering a seal pattern on any one of the first and second substrates, contacting one end of the electrical connection pattern with the second electrode and bonding the two substrates Method for manufacturing an organic light emitting device comprising a. Forming an array element at a crossing point on the gate line and the data line crossing each other on the first substrate; Forming an electrical connection pattern on the first substrate in contact with the array element; Vacuum depositing a metal material having a work function value of 4 eV or less on the second substrate to form a first electrode having a first thickness; Forming an inorganic material layer having a second thickness by vacuum depositing the inorganic material over the first electrode; Vacuum depositing the metal material on the inorganic material layer to a third thickness to form an electron injection layer in which the metal material is diffused into the inorganic material layer to chemically bond the inorganic material and the metal material; Forming a multilayer organic electroluminescent layer over the electron injection layer; Forming a second electrode on the organic electroluminescent layer using a conductive material having a work function greater than the metal material; A step of bordering a seal pattern on any one of the first and second substrates, contacting one end of the electrical connection pattern with the second electrode and bonding the two substrates Method for manufacturing an organic light emitting device comprising a. The method according to claim 12 or 13, The metal material is aluminum (Al) manufacturing method of an organic light emitting device. The method according to claim 12 or 13, The conductive material is an indium tin oxide (ITO) method of manufacturing an organic light emitting device. The method according to claim 12 or 13, The inorganic material is an organic electroluminescent device manufacturing method of one selected from LiF, Li ₂ O, SiO ₂ . The method according to claim 12 or 13, Forming the multilayer organic electroluminescent layer is Forming an electron transporting layer; Forming a red, green, and blue organic light emitting layer that is sequentially repeated for each subpixel on the electron transporting layer; Forming a hole transporting layer on the organic light emitting layer; Forming a hole injection layer over the hole transporting layer Method for producing an organic electroluminescent device comprising a. The method according to claim 12 or 13, Forming an array element at the intersection of the gate wiring and the data wiring and the interconnection on the first substrate is Forming a polysilicon pattern on the substrate; Forming a gate insulating film on an entire surface of the polysilicon pattern; Forming a gate electrode on the gate insulating layer to correspond to the polysilicon, including a gate wiring; Performing p + doping on the entire surface of the substrate; Forming an interlayer insulating film over the gate electrode and the gate wiring; Forming a source and drain electrode on the interlayer insulating layer, the source and drain electrodes respectively contacting the polysilicon pattern, and a data line crossing the gate line; Method for producing an organic electroluminescent device comprising a. The method of claim 18, And forming a protective layer on the entire surface of the source and drain electrodes and the data line. The method of claim 19, And forming a connection electrode in contact with the drain electrode on the passivation layer. The method of claim 18, Forming the polysilicon pattern Forming an amorphous silicon pattern on the first substrate; Crystallizing the amorphous silicon pattern into a polysilicon pattern Method for producing an organic electroluminescent device comprising a. The method of claim 12, The first thickness is a method of manufacturing an organic light emitting device is 100 kPa to 150 kPa. The method of claim 13, The first thickness is a method of manufacturing an organic light emitting device is 1000kPa to 2000kPa. The method of claim 13, The second thickness is a method of manufacturing an organic light emitting device is 5 ~ 10Å. The method of claim 13, The third thickness is a method of manufacturing an organic light emitting device of 80 kHz to 100 kHz.

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