KR20100063292A - Top emission type organic electro-luminescence device and method for fabricating of the same - Google Patents

Abstract

PURPOSE: A top emission type organic electro-luminescence element and a method for manufacturing the same are provided to minimize the reflection of external light and improve contrast. CONSTITUTION: A semiconductor layer(201) is formed on a first substrate(101) which is composed of silicon. A gate insulation layer(203) is formed on the semiconductor layer. A gate electrode(205) and a gate wire are formed on the upper side of the gate insulation layer in response with the semiconductor layer. A first interlayer insulation layer(207a) is formed on the entire surface of the gate electrode and the gate wire.

Description

Top emission type organic electroluminescent device and method for fabricating of the same

The present invention relates to an organic light emitting device having a top emission type, and to an organic light emitting device capable of blocking external light.

Until recently, cathode ray tubes (CRT) have been mainly used as display devices. However, in recent years, flat panel such as plasma display panel (PDP), liquid crystal display device (LCD), organic electro-luminescence device (OLED), which can replace CRT Display devices are widely researched and used.

Among the flat panel display devices as described above, the organic light emitting display device (hereinafter referred to as OLED) is a self-light emitting device, and since the backlight used in the liquid crystal display device which is a non-light emitting device is not necessary, a light weight can be achieved.

In addition, the viewing angle and contrast ratio are superior to the liquid crystal display device, and it is advantageous in terms of power consumption, it is possible to drive the DC low voltage, the response speed is fast, and the internal components are solid, so it is strong against external shock, and the operating temperature range is also high. It has a wide range of advantages.

In particular, since the manufacturing process is simple, there is an advantage that can reduce the production cost more than the conventional liquid crystal display device.

OLEDs having these characteristics are largely divided into a passive matrix type and an active matrix type. The passive matrix type constitutes a device in a matrix form while crossing signal lines, whereas an active matrix type is a pixel. The thin film transistor, which is a switching element that turns on / off, and the driving thin film transistor which transmits current and the capacitor which maintains voltage for one frame are positioned per pixel.

In recent years, the passive matrix type has many limited elements such as resolution, power consumption, and lifespan. Accordingly, active matrix type OLEDs capable of realizing high resolution and large screens have been actively studied.

In addition, the OLED is divided into a top emission type and a bottom emission type according to the direction of light emitted. The bottom emission type has a high degree of stability and a high degree of freedom in processing, and a limitation of an aperture ratio. There is a problem that is difficult to apply to high resolution products.

Therefore, in recent years, research on the top emission method having high opening ratio and high resolution has been actively conducted.

1 is a diagram schematically showing a cross section of a general active matrix type OLED, and the OLED is a top emission type.

As shown, the OLED 10 is composed of a first substrate 1 and a second substrate 2 facing the first substrate 1, wherein the first and second substrates 1, 2 are bonded to each other. The adhesive layer is spaced apart from each other through a protective layer 5 having sex.

In detail, the driving thin film transistor DTr is formed in each pixel area on the first substrate 1, and the first electrode 11 and the first electrode connected to each driving thin film transistor DTr are formed. An organic light emitting layer 13 emitting light of a specific color on the upper part of (11), and a second electrode 15 is formed on the organic light emitting layer 13.

The organic light emitting layer 13 expresses colors of red, green, and blue. In general, separate organic materials 13a, 13b, and 13c emitting red, green, and blue colors are used for each pixel.

The first and second electrodes 11 and 15 and the organic light emitting layer 13 formed therebetween form an organic light emitting diode. In this case, the OLED 10 having such a structure configures the first electrode 11 as an anode and the second electrode 15 as a cathode.

On the other hand, the second substrate 2 can be removed to provide the OLED 10 having flexible properties.

However, the OLED 10 has a disadvantage in that the contrast is greatly reduced according to the intensity of the external light. Therefore, the external light blocking polarizing plate 50 is attached to the OLED 10 in order to prevent the lowering of the contrast caused by the external light.

That is, the OLED 10 improves contrast by forming a polarizing plate 50 that blocks external light incident from the outside in the transmission direction of light emitted through the organic light emitting layer 13.

The polarizing plate 50 is a circular polarizing plate for blocking external light, and is composed of a 1 / 4λ retardation plate 20 and a linear polarizing plate 30 attached to an outer surface of the second substrate 2. Here, the structure of the circular polarizer will be described in more detail with reference to FIG. 2.

2 is a view schematically showing the structure of a circular polarizing plate.

As shown, the circularly polarizing plate 50 includes a first adhesive layer 21a, a 1 / 4λ retardation plate 20 and a 1 / 4λ retardation plate for attaching the circularly polarizing plate 50 to the OLED (10 in FIG. 1). 20) and a second adhesive layer 21b for attaching the linear polarizing plate 30 to each other.

Here, the linear polarizing plate 30 is a polarizing layer 31 for changing the polarization characteristics of the light, and the first and second TAC films formed on both sides of the polarizing layer 31 to protect and support the polarizing layer 31 ( 33a, 33b).

The surface treatment layer 40 further includes a surface treatment layer 40 on one side of the second TAC film 33b. The surface treatment layer 40 includes an anti-glare layer including silica beads (not shown). Or a hard coating layer for preventing damage to the surface of the polarizer 50.

At this time, the lower portion of the first adhesive layer 21a may include a separate protective layer (not shown), which is detached in the process of attaching the circularly polarizing plate 50 to expose the first adhesive layer 21a, and is carried and transported. In the process of protecting the first adhesive layer (21a) from contamination.

Accordingly, external light incident from the outside into the OLED (10 in FIG. 1) is incident through the circularly polarizing plate 50 formed of the 1 / 4λ retardation plate 20 and the linear polarizing plate 30, and the incident external light is the first. Reflected by the electrode 11 in FIG. 1, the polarization direction thereof is changed. Therefore, the incident external light does not pass through the circular polarizing plate 50 and thus does not come out to the outside, causing extinction interference.

For this reason, contrast is improved by blocking external light.

However, as described above, the circularly polarizing plate 50 attached to the OLED (10 of FIG. 1) has too many components to increase manufacturing cost.

In addition, each layer of the circular polarizing plate 50 has a thickness of at least several tens of micrometers, so that the circular polarizing plate 50 has a thickness of at least 200 µm or more. Thus, it causes a problem of increasing the overall thickness of the OLED (10 in FIG. 1).

In addition, a loss of light occurs by the first and second adhesive layers 21a and 21b, thereby causing a problem in that luminance is reduced.

The present invention has been made to solve the above problems, and a first object of the present invention is to provide a thin OLED.

In addition, the second object is to reduce the process cost of the OLED.

In addition, the third object is to improve luminance.

In order to achieve the above object, the present invention includes a first substrate formed with a driving thin film transistor and an organic light emitting diode; A first protective layer covering the driving thin film transistor and the organic light emitting diode; A phase difference layer formed on the first protective layer; A second protective layer formed on the retardation layer and covering the retardation layer; A linear polarization layer formed on the second protective layer; It is formed on the linear polarization layer, and includes a third protective layer covering the linear polarization layer, the light emitted from the organic light emitting diode to provide an organic light emitting device is driven in a top light emitting method transmitted to the upper phase retardation layer do.

In this case, the retardation layer and the linear polarization layer are formed of a liquid crystal polymer (LCP) including a cholesteric liquid crystal, and the retardation layer has a 1/4 λ wavelength layer.

In addition, the first to the third protective layer is an inorganic insulating material or a polyacrylate, polyimide containing silicon nitride (SiNx), silicon oxide (Si0 ₂ ) or alumina (Al ₂ O ₃ ) , At least one selected from among organic insulating materials including polyamide or benzocyclobutene (BCB), which is composed of a single layer or a multilayer, and the first substrate is a flexible glass substrate or a plastic, stainless steel ( stainless steel).

The driving thin film transistor includes a semiconductor layer, a gate electrode, a source and a drain electrode, and the organic light emitting diode includes a first electrode, an organic light emitting layer, and a second electrode connected to the driving thin film transistor.

In addition, the present invention comprises the steps of forming a driving thin film transistor on one surface of the first substrate; Forming an organic light emitting diode electrically connected to the driving thin film transistor; Forming a first passivation layer covering the driving thin film transistor and the organic light emitting diode; Forming a phase difference layer on the first passivation layer; Forming a second protective layer on the retardation layer to cover the retardation layer; Forming a linear polarization layer on the second protective layer; It provides an organic electroluminescent device manufacturing method comprising the step of forming a third protective layer covering the linear polarization layer on the linear polarization layer.

The first to third protective layers may be formed by chemical vapor deposition (CVD), sputter or inkjet devices, nozzle coating, bar coating, slit coating, Forming through an spin coating apparatus or a printing apparatus, wherein the retardation layer and the linear polarization layer form an alignment film; Rubbing the alignment layer; The liquid crystal polymer layer is formed on the alignment layer.

In this case, the liquid crystal polymer layer is formed through an inkjet apparatus, a nozzle coating, a bar coating, a slit coating, a spin coating apparatus, or a print apparatus.

As described above, according to the present invention, a thin film is formed on the first passivation layer to form a phase delay layer for converting linearly polarized light into circularly polarized light and a linearly polarized layer for passing only light in a direction parallel to the light transmission axis. By forming them so as to be surrounded by the second and third protective layers, respectively, the reflection of external light is minimized, the contrast is further improved, and the overall thickness of the device can be reduced. This has the effect of reducing the manufacturing cost.

In addition, there is an effect that can prevent the problem that the brightness is reduced by the loss of light by the existing adhesive layer.

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

FIG. 3 is a cross-sectional view schematically illustrating a top emission OLED according to an exemplary embodiment of the present invention, and FIG. 4 is an enlarged cross-sectional view of a portion of FIG. 3.

As illustrated, the OLED 100 includes a driving thin film transistor DTr and an organic light emitting diode E formed on the first substrate 101.

Here, the semiconductor layer 201 is formed on the first substrate 101. The semiconductor layer 201 is made of silicon, and the central portion thereof has a high concentration of impurities on both sides of the active region 201a and the active region 201a. The doped source and drain regions 201b and 201c are formed.

The gate insulating film 203 is formed on the semiconductor layer 201.

A gate electrode 205 and a gate wiring extending in one direction are formed on the gate insulating film 203 so as to correspond to the semiconductor layer 201a.

In addition, a first interlayer insulating film 207a is formed on the entire surface of the gate electrode 205 and the gate wiring (not shown). At this time, the first interlayer insulating film 207a and the gate insulating film 203 below are formed in an active region ( 201a) first and second semiconductor layer contact holes 209a and 209b exposing the source and drain regions 201b and 201c located at both sides thereof, respectively.

Next, an upper portion of the first interlayer insulating layer 207a including the first and second semiconductor layer contact holes 209a and 209b is spaced apart from each other and exposed through the first and second semiconductor layer contact holes 209a and 209b. And source and drain electrodes 211 and 213 in contact with the drain regions 201b and 201c, respectively.

And a second interlayer having a drain contact hole 215 exposing the drain electrode 213 over the first interlayer insulating film 207a exposed between the source and drain electrodes 211 and 213 and the two electrodes 211 and 213. An insulating film 207a is formed.

At this time, the semiconductor layer 201 including the source and drain electrodes 211 and 213 and the source and drain regions 201b and 201c in contact with the electrodes 211 and 213 and the gate insulating layer formed on the semiconductor layer 201. The 203 and the gate electrode 205 form a driving thin film transistor DTr.

Although not shown in the drawing, data wirings (not shown) defining pixel areas are formed to cross the gate wirings (not shown).

In addition, the organic light emitting diode is formed of a material having a relatively high work function, for example, in a region that is connected to the drain electrode 213 of the driving thin film transistor DTr and substantially displays an image on the second interlayer insulating film 207b. As one component constituting (E), a first electrode 220 constituting an anode is formed.

The first electrode 220 is formed for each pixel region, and a bank 221 is positioned between the first electrodes 220 formed for each pixel region.

That is, the first electrode 220 is formed in a structure in which the banks 221 are used as boundary portions for each pixel region, and the pixel regions are separated.

The organic light emitting layer 225 is formed on the first electrode 220.

Here, the organic light emitting layer 225 may be composed of a single layer made of a light emitting material, and in order to increase the light emitting efficiency, a hole injection layer, a hole transporting layer, an emitting material layer, an electron It may be composed of multiple layers of an electron transporting layer and an electron injection layer.

In addition, a second electrode 227 forming a cathode is formed on the entire surface of the organic light emitting layer 225.

The first and second electrodes 220 and 227 and the organic light emitting layer 225 formed therebetween form an organic light emitting diode (E).

In this case, the second electrode 227 has a double layer structure, and a double layer structure in which a transparent conductive material is thickly deposited on a semitransparent metal film in which a thin metal material having a low work function is deposited.

Therefore, the light emitted from the organic light emitting layer 225 is driven by the top emission method emitted toward the second electrode 227.

When a predetermined voltage is applied to the first electrode 220 and the second electrode 227 according to the selected color signal, the OLED 100 may be formed from holes and second electrodes 227 injected from the first electrode 220. The provided electrons are transported to the organic light emitting layer 225 to form an exciton, and when such excitons transition from the excited state to the ground state, light is generated and emitted in the form of visible light.

At this time, since the emitted light passes through the transparent second electrode 227 to the outside, the OLED 100 implements an arbitrary image.

The first passivation layer 105a is formed on the driving thin film transistor DTr and the organic light emitting diode E to protect the driving thin film transistor DTr and the organic light emitting diode E.

In this case, the second substrate (2 of FIG. 1) may be further provided to allow the first and second substrates (1, 2 of FIG. 1) to be spaced apart from each other, and the present invention has recently been performed in a notebook or personal digital assistant (PDA). In order to provide an OLED 100 which is lighter, lighter than the glass, and has a flexible characteristic to be applicable to these small portable terminals such as), the second substrate (2 of FIG. 1) has been removed. As an example.

Accordingly, the first substrate 101 is preferably made of a flexible glass substrate or plastic, stainless steel, or the like having flexible characteristics.

In addition, a phase delay layer 120 for converting linearly polarized light into circularly polarized light and linearly polarized light into linearly polarized light and a linearly polarized light layer 130 for passing only light in a direction parallel to the light transmission axis are formed on the first passivation layer 105a. The phase delay layer 120 and the linear polarization layer 130 are surrounded by the second and third protective layers 105b and 105c, respectively.

Here, the phase delay layer 120 and the linear polarization layer 130 are liquid crystal polymers (LCPs) including cholesteric liquid crystals which can be formed and maintained in a crystal state even in an alignment film (not shown) and in a molten state (not shown). O).

In this case, the stacking order of the linear polarization layer 130 and the phase delay layer 120 is preferably a structure in which the linear polarization layer 130 is disposed close to the incident direction of external light and the phase delay layer 120 is disposed therein. Another light transmissive layer (not shown) may be interposed between the linear polarizing layer 130 and the phase delay layer 120.

Therefore, the OLED 100 is greatly reduced in contrast with the intensity of the external light, the contrast is reduced by the external light, the present invention is incident from the outside by the phase delay layer 120 and the linear polarization layer 130 By minimizing the reflection of external light, the degradation of contrast is prevented and improved.

Here, the phase delay layer 120 is to have a 1/4 λ wavelength layer.

In this case, the liquid crystal of the liquid crystal polymer (not shown) has a selective reflection characteristic of reflecting the incident light only a specific wavelength according to the rotation pitch, and at this time, the polarization state of the reflected light is also determined according to the rotation direction of the liquid crystal.

Therefore, the external light incident from the outside absorbs the component in the direction along the absorption axis of the linear polarization layer 130 and transmits the component in the direction along the transmission axis. The component in the direction along the transmission axis is converted into circularly polarized light that is rotated in one direction while passing through the phase delay layer 120 and then reflected by the first electrode 220 of the organic light emitting diode E.

When reflected, the circularly polarized light rotating in one direction becomes circularly polarized light rotating in the other direction, and is converted into linearly polarized light in a direction orthogonal to the initial transmission axis while passing through the phase delay layer 120. Therefore, this linearly polarized light is absorbed by the absorption axis of the linear polarization layer 130 and does not come out to the outside, causing extinction interference.

Therefore, external light reflection is minimized, and contrast is further improved.

Particularly, in the present invention, the phase delay layer 120 and the linear polarization layer 130 for blocking external light are formed in a thin film shape, whereby a circular polarizing plate (50 in FIG. 1) having a large number of components and having a thickness of at least 200 μm is formed. Compared to the existing one, the thickness of the device can be made thinner.

In addition, manufacturing cost can be reduced.

In addition, the phase delay layer 120 and the linear polarization layer 130 of the present invention are formed directly on the first substrate 101 in the form of a thin film, and thus do not require separate adhesive layers (21a and 21b in FIG. 1). Therefore, it is possible to prevent a problem that the loss of light occurs due to the adhesive layer (21a, 21b of FIG. 1) of the conventional circular polarizing plate (50 of FIG. 1), the brightness is reduced.

Here, the phase delay layer 120 and the linear polarization layer 130 may be configured using spin coating, slit coating, roll printing method, inkjet coating method, This will be described in more detail with reference to FIGS. 5A to 5G.

5A to 5G are cross-sectional views of manufacturing an organic light emitting diode substrate of an upper emission type OLED according to an exemplary embodiment of the present invention.

As illustrated, the driving thin film transistor DTr is formed on the substrate 101, and the driving thin film transistor Dtr is formed of the semiconductor layer 201 and the gate insulating layer 203 and the gate electrode formed on the semiconductor layer 201. 205 and the first interlayer insulating film 207a and the source and drain electrodes 211 and 213 formed on the gate electrode 205.

And a second interlayer having a drain contact hole 215 exposing the drain electrode 213 over the first interlayer insulating film 207a exposed between the source and drain electrodes 211 and 213 and the two electrodes 211 and 213. The insulating film 207b is formed.

Although not shown in the drawings, the method for forming the same is described in detail. After depositing amorphous silicon, coating of photoresist, exposure through a mask, development of exposed photoresist, and remaining amorphous photoresist exposed after development The semiconductor layer 201 is formed by performing a series of processes called patterning through a mask process such as etching the silicon layer and ashing or stripping the remaining photoresist.

In this case, the method may further include crystallizing polysilicon by heat treatment after dehydrogenation of the semiconductor layer 201.

Next, the second insulating material and the first metal layer are sequentially deposited on the substrate 101 on which the semiconductor layer 201 is formed, and then, as described above, the second insulating material is formed at the center of the semiconductor layer 201 through a mask process. Is formed of the gate insulating film 203.

The first metal layer is formed as the gate electrode 205 with the gate insulating film 203 as a lower layer.

Here, it is preferable that the second insulating material is any one of silicon nitride (SiNx) or silicon oxide (Si0 ₂ ), which is an inorganic insulating material.

The first metal layer is formed by depositing one or two or more materials selected from metal materials such as aluminum (Al) or aluminum alloy (AlNd), molybdenum (Mo), nickel (Ni), tungsten (W), and the like. It is preferable to set it as.

Next, in the substrate 101 on which the semiconductor layer 201 is formed, the gate electrode 205 and the gate insulating film 203 exposed to the outside of the gate wiring (not shown) are etched and removed, and then, the substrate 101 is applied to the substrate 101. N + or p + doping is performed by ion implantation having a dose amount.

At this time, the portion of the semiconductor layer 201 where the ion implantation is blocked by the gate electrode 205 forms the active layer 201a, and the other ion implanted active regions are the source and drain regions 201b and 201c. Will form.

As a result, the semiconductor layer 201 including the active region 201a and the source and drain regions 201b and 201c is completed.

Next, an inorganic insulating material is deposited on the exposed source and drain regions 201b and 201c including the gate electrode 205 and patterned by performing a mask process, thereby forming source and drain regions 201b on both sides of the gate electrode 205. And a first interlayer insulating film 207a having first and second semiconductor layer contact holes 209a and 209b exposing a portion thereof, respectively.

Next, the first and second semiconductor layers are deposited by depositing a metal material on the entire surface of the substrate 101 having the first and second semiconductor layer contact holes 209a and 209b and forming a mask process. Source and drain electrodes 211 and 213 in contact with the source and drain regions 201b and 201c are formed through the contact holes 209a and 209b, respectively.

In this case, the source and drain electrodes 211 and 213 are spaced apart from each other with the gate electrode 205 therebetween.

Next, an organic insulating material such as photo acryl or benzocyclobutene (BCB) is coated on the entire surface of the substrate 101 on which the source and drain electrodes 211 and 213 are formed, and then patterned through a mask process. A second interlayer insulating film 207b is formed over the entire surface.

In this case, the second interlayer insulating film 207b has a drain electrode contact hole 215 exposing the drain electrode 213.

Next, as shown in FIG. 5B, an organic light emitting diode E is formed on the second interlayer insulating film 207b, and the organic light emitting diode E is formed of the first and second electrodes 220 and 227. ) And an organic light emitting layer 225 formed therebetween.

Here, the organic light emitting diode E forms an anode as an constituent element of the organic light emitting diode E on the second interlayer insulating film 207b, and then forms an anode. The partition wall 221 is formed on the first electrode 220 by applying and patterning a photosensitive organic insulating material, for example, photo acryl or benzocyclobutene (BCB) on the first electrode 220. Form.

The partition wall 221 is formed in a matrix type having a lattice structure as a whole to distinguish between pixel areas.

Next, an organic light emitting material is coated or deposited on the partition 221 to form the organic light emitting layer 225.

Next, the organic light emitting diode E is formed by forming a second electrode 227 having a thick transparent conductive material deposited on the translucent metal film having a thin work function deposited on the organic light emitting layer 225. You are done.

Next, as shown in FIG. 5C, the first passivation layer 105a is formed on the organic light emitting diode E. Referring to FIG.

The first protective layer 105a may be an inorganic insulating material such as silicon nitride (SiNx) or silicon oxide (Si0 ₂ ) or alumina (Al ₂ O ₃ ), or polyacrylate, polyimide, polyamide ( Polyamide) or benzocyclobutene (BCB) is formed of a single layer or a multilayer with one selected from an organic insulating material, wherein when the first protective layer (105a) is formed of an inorganic insulating material, chemical vapor deposition (chemical vapor deposition): CVD) or sputtering equipment.

Alternatively, when the first protective layer 105a is to be formed of an organic insulating material, the first protective layer 105a may be an inkjet device, a nozzle coating, a bar coating, a slit coating, It is formed by coating the entire surface using a spin coating device or a print device.

The thickness of this first protective layer 105a is about several micrometers.

Next, as shown in FIG. 5D, the phase delay layer 120 is formed on the first passivation layer 105a, and the phase delay layer 120 is formed on the first passivation layer 105a. The alignment layer 123 is formed and the surface of the first alignment layer 123 is oriented in a predetermined direction by using a rubbing or photoalignment method.

Next, the first liquid crystal polymer film 127 including the cholesteric liquid crystal 125 is formed on the first alignment layer 123, thereby completing.

The first liquid crystal polymer film 127 may be formed on the front surface using an inkjet device, a nozzle coating, a bar coating, a slit coating, a spin coating apparatus, or a print apparatus. After coating, the liquid crystal polymer layer 127 is formed by curing for a predetermined time.

At this time, the retardation layer 120 is to have a 1/4 λ wavelength layer, the thickness of the retardation layer 120 is formed of about several ㎛, has a thickness of at least 10㎛.

The retardation layer 120 may be formed to be larger than the effective light emission area of the driving thin film transistor DTr and the organic light emitting diode E in all the pixel regions formed on the first substrate 101.

Next, as shown in FIG. 5E, the second passivation layer 105b is formed on the phase delay layer 120, and the second passivation layer 105b is the same as the first passivation layer 105a previously formed. Form through the way.

The second protective layer 105b is preferably formed to cover all three surfaces of the phase difference layer 120, and the thickness of the second protective layer 105b is about several micrometers.

Next, as shown in FIG. 5F, the linear polarization layer 130 is formed on the second protective layer 105b. The linear polarization layer 130 also includes an alignment layer 133 and a cholesteric liquid crystal 135. It consists of a liquid crystal polymer film (137).

Therefore, the formation method thereof is the same as the previous method of forming the retardation layer 120. The second alignment layer 133 is formed on the second passivation layer 105b, and the second alignment layer 133 is formed using a rubbing or photoalignment method. The surface of is orientated in a constant direction.

Next, the second liquid crystal polymer film 137 including the cholesteric liquid crystal 135 is formed on the second alignment layer 133, thereby completing.

The second liquid crystal polymer film 137 may also be formed on the front surface using an inkjet device, a nozzle coating, a bar coating, a slit coating, a spin coating apparatus, or a print apparatus. After coating, it is formed by curing for a certain time.

At this time, the thickness of the linear polarizing layer 130 is formed to about several ㎛, has a thickness of at least 10 ㎛.

The linear polarization layer 130 is preferably formed larger than the effective light emitting area of the driving thin film transistor DTr and the organic light emitting diode E formed on the first substrate 101.

Next, as shown in FIG. 5G, a third passivation layer 105c is formed on the linear polarization layer 130, and the third passivation layer 105c includes the first and second passivation layers 105a, It is formed through the same method as 105b).

The third protective layer 105c is preferably formed to cover all three surfaces of the linear polarization layer 130, and the thickness of the third protective layer 105c is about several micrometers.

As a result, the retardation layer 120 and the linear polarization layer 130 according to the embodiment of the present invention complete the OLED 100 formed of a thin film.

In this case, the first to third protective layers 105a, 105b, 105c, the retardation layer 120, and the linear polarization layer 130 except for the driving thin film transistor DTr and the organic light emitting diode E of the OLED 100 may be formed. The thickness of the optical means for blocking external light is formed to a thickness of about 40㎛ or less.

Table 1 below is the data comparing the respective thicknesses of the components of the conventional circular polarizing plate (50 in FIG. 1) with the respective thicknesses of the optical means for blocking external light of the present invention.

Circular polarizer
Retarder > 50 μm 1st and 2nd TAC Film (Angle)> 50㎛ Polarizing layer 40 to 120㎛
Optical means for blocking external light of the present invention Retardation layer  <10 μm First to third
Protective layer  (Angle) <10 μm Linear polarization layer  <10 μm

Table (1)

Referring to Table (1), it can be seen that the thickness of the existing circular polarizing plate (50 in Figure 1) is at least 200㎛, it can be confirmed that the optical means for blocking external light of the present invention has a thickness of only 40㎛ or less. Can be.

In particular, the existing circular polarizing plate (50 of FIG. 1) is provided with a separate adhesive layer (21a, 21b of FIG. 1) for attaching the circular polarizing plate (50 of FIG. 1) on the substrate 101, the circular polarizing plate (FIG. The thickness of 1) 50) becomes thicker.

Therefore, the present invention minimizes the reflection of external light, further improves the contrast, and at the same time, the thickness of the device as a whole can be made thinner than that of the conventional circular polarizing plate (50 in FIG. 1) having a thickness of 200 μm or more. .

In addition, the phase delay layer 120 and the linear polarization layer 130 of the present invention is formed directly on the first substrate 101 in a thin film form, thereby forming a conventional circular polarizing plate (50 in FIG. 1) on the substrate 101 Since the adhesive layers (21a and 21b of FIG. 1) are not required for adhesion, the problem of light loss due to the loss of light caused by the adhesive layers (21a and 21b of FIG. 1) can be prevented.

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.

1 is a schematic cross-sectional view of a typical active matrix type OLED.

2 is a view schematically showing the structure of a circular polarizing plate.

3 is a cross-sectional view schematically showing a top-emitting OLED according to an embodiment of the present invention.

4 is an enlarged cross-sectional view of a portion of FIG. 3;

5a to 5g are cross-sectional views of manufacturing an organic light emitting diode substrate of an upper emission type OLED according to an embodiment of the present invention.

Claims (11)

A first substrate on which a driving thin film transistor and an organic light emitting diode are formed; A first protective layer covering the driving thin film transistor and the organic light emitting diode; A phase difference layer formed on the first protective layer; A second protective layer formed on the retardation layer and covering the retardation layer; A linear polarization layer formed on the second protective layer; A third passivation layer formed on the linear polarization layer and covering the linear polarization layer Includes, the light emitted from the organic light emitting diode is an organic electroluminescent device is driven in a top light emitting method that passes through the phase difference layer. The method of claim 1, And the retardation layer and the linear polarization layer are formed of a liquid crystal polymer (LCP) including a cholesteric liquid crystal. The method of claim 1, The retardation layer is an organic light emitting display device having a 1/4 λ wavelength layer. The method of claim 1, The first to third protective layers may be an inorganic insulating material or polyacrylate, polyimide, polyimide including silicon nitride (SiNx), silicon oxide (Si0 ₂ ) or alumina (Al ₂ O ₃ ). An organic electroluminescent device comprising a single layer or multiple layers of at least one material selected from organic insulating materials including amide (polyamide) or benzocyclobutene (BCB). The method of claim 1, The first substrate is an organic light emitting display device comprising one selected from a flexible glass substrate, plastic, and stainless steel. The method of claim 1, The driving thin film transistor may include a semiconductor layer, a gate electrode, a source, and a drain electrode. The method of claim 1, The organic light emitting diode includes an organic light emitting diode including a first electrode, an organic light emitting layer, and a second electrode connected to the driving thin film transistor. Forming a driving thin film transistor on one surface of the first substrate; Forming an organic light emitting diode electrically connected to the driving thin film transistor; Forming a first passivation layer covering the driving thin film transistor and the organic light emitting diode; Forming a phase difference layer on the first passivation layer; Forming a second protective layer on the retardation layer to cover the retardation layer; Forming a linear polarization layer on the second protective layer; Forming a third protective layer covering the linear polarization layer on the linear polarization layer; Organic electroluminescent device manufacturing method comprising a. The method of claim 8, The first to third protective layers may be formed by chemical vapor deposition (CVD), sputter or inkjet devices, nozzle coating, bar coating, slit coating, An organic electroluminescent device manufacturing method formed through a spin coating device or a print device. The method of claim 8, The retardation layer and the linear polarization layer Forming an alignment film; Rubbing the alignment layer; Forming a liquid crystal polymer layer on the alignment layer Organic electroluminescent device manufacturing method formed by. The method of claim 10, The liquid crystal polymer layer may be formed using an inkjet device, a nozzle coating, a bar coating, a slit coating, a spin coating device, or a printing device. .

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