KR101458908B1 - Organic light emitting diode display and method for manufacturing the same - Google Patents

Abstract

The first, second, and third pixels may include a first electrode, a first electrode, and a second electrode, respectively, wherein the first, second, and third pixels include a first pixel, a second pixel, A light emitting layer disposed between the first electrode and the second electrode, and an auxiliary layer disposed below the first electrode and including an insulating material, wherein the first pixel and the second Wherein the first electrode of the pixel comprises a first transparent conductive layer and a semitransparent conductive layer positioned between the auxiliary layer and the first transparent conductive layer and forming a fine resonance with the second electrode, One electrode is formed on the first transparent conductive layer, a semi-transparent conductive layer positioned between the auxiliary layer and the first transparent conductive layer and forming a fine resonance with the second electrode, And the first transparent conductive And an organic light-emitting display device includes an etching ratio of the different second transparent conductive layer and to a method of manufacturing the same.

Fine resonance, green pixel, pixel electrode, etching characteristic, insulating film

Description

TECHNICAL FIELD [0001] The present invention relates to an organic light emitting diode (OLED) display device,

The present invention relates to an organic light emitting display and a method of manufacturing the same.

2. Description of the Related Art In recent years, a cathode ray tube (CRT) has been replaced by a liquid crystal display (LCD) in accordance with such a demand.

However, a liquid crystal display device requires not only a backlight but also a response speed and a viewing angle.

Recently, organic light emitting diode (OLED) displays have been attracting attention as display devices capable of overcoming these limitations.

The organic light emitting display includes two electrodes and a light emitting layer disposed therebetween. Electrons injected from one electrode and holes injected from the other electrode are combined in the light emitting layer to form an exciton And the exciton emits light while emitting energy.

Since the organic light emitting display device is of a self-emission type and does not require a separate light source, it is advantageous not only in terms of power consumption but also in response speed, viewing angle, and contrast ratio.

On the other hand, the organic light emitting display includes a plurality of pixels such as a red pixel, a blue pixel, and a green pixel, and these pixels can be combined to represent a full color.

At this time, the red pixel, the blue pixel, and the green pixel can express a color by including a red luminescent layer, a blue luminescent layer, and a green luminescent layer, respectively. Such a light emitting layer can be deposited for each pixel by using a fine shadow mask. However, there is a limitation in depositing the light emitting layer for each pixel using the fine shadow mask while the display device is becoming large.

Accordingly, a red light emitting layer, a blue light emitting layer, and a green light emitting layer are sequentially stacked on the entire display device using an open mask to emit white light, and a color filter is placed at a position where the emitted light passes, , Green, and blue.

However, due to the color reproducibility limit of the color filter itself, the light passing through the color filter has to exhibit the same or lower color reproducibility. In this case, it is difficult to achieve high color reproducibility required by the National Television Systems Committee (NTSC).

Therefore, a problem to be solved by the present invention is to achieve high color reproducibility in a white light emitting organic light emitting display.

The OLED display according to an embodiment of the present invention includes a first pixel, a second pixel, and a third pixel that display different colors, wherein the first, second, and third pixels A first electrode, a second electrode facing the first electrode, a light emitting layer disposed between the first electrode and the second electrode, and an auxiliary layer located under the first electrode and including an insulating material Wherein the first electrode of the first pixel and the second pixel includes a first transparent conductive layer and a semitransparent conductive layer which is located between the auxiliary layer and the first transparent conductive layer and forms a fine resonance with the second electrode, A first electrode of the third pixel includes the first transparent conductive layer, a semi-transparent conductive layer which is located between the auxiliary layer and the first transparent conductive layer and forms a fine resonance with the second electrode, The phase of the first transparent conductive layer It is formed in which a second transparent conductive layer different ratio of the first transparent conductive layer and etching.

Wherein the organic light emitting display further comprises a fourth pixel that does not display color, the fourth pixel includes a first electrode including the second transparent conductive layer, a second electrode facing the first electrode, A light emitting layer disposed between the first electrode and the second electrode, and an auxiliary layer disposed below the first electrode and including an insulating material.

Wherein each of the first, second, third, and fourth pixels includes a thin film transistor electrically connected to the first electrode, and a protective film formed between the thin film transistor and the first electrode, And the auxiliary layer may comprise the same material.

The protective layer and the auxiliary layer may include at least one selected from silicon nitride (SiNx), silicon oxide (SiO ₂₎ and silicon oxynitride (SiON).

The sum of the thicknesses of the auxiliary layer and the first electrode of the fourth pixel may be 500 to 2000 ANGSTROM.

One of the first transparent conductive layer and the second transparent conductive layer may include crystalline ITO and the other may include ITO formed from IZO or an amorphous state.

The first pixel may be a red pixel, the second pixel may be a blue pixel, and the third pixel may be a green pixel.

The light emitting layer includes a plurality of sub-emission layers that emit light of different wavelengths, and light of different wavelengths may be combined to emit white light.

The first pixel, the second pixel, and the third pixel may each further include a color filter formed under the first electrode.

A method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention includes forming a thin film transistor on a substrate in an OLED display device including a red pixel, a blue pixel, a green pixel, and a white pixel, Forming an auxiliary layer on the passivation layer, patterning the passivation layer and the auxiliary layer to form a plurality of contact holes for exposing the thin film transistor on the passivation layer, and forming an auxiliary layer located in each pixel Forming a first electrode on an auxiliary layer located in each pixel, forming a light emitting layer on the first electrode, and forming a second electrode on the light emitting layer.

Wherein forming the first electrode comprises forming a semitransparent conductive layer on the auxiliary layer of the red, green and blue pixels, respectively, forming a first transparent conductive layer on the semitransparent conductive layer of the red, And forming a second transparent conductive layer on the auxiliary layer of the first transparent conductive layer and the white pixel of the green pixel, respectively.

The forming of the first electrode includes sequentially laminating a semi-transparent conductive layer and a first transparent conductive layer on the entire surface of the substrate, applying a first photosensitive film on the first transparent conductive layer and patterning the first photosensitive conductive film to form red, Forming a first photosensitive pattern by photolithographically etching the first transparent conductive layer and the semitransparent conductive layer using the first photosensitive pattern to form a first transparent conductive layer and a semitransparent conductive layer on the red, Laminating a second transparent conductive layer on the entire surface of the substrate including the semitransparent conductive layer; applying and patterning a second photosensitive film on the second transparent conductive layer to form a second photosensitive pattern on the green pixel and the white pixel, respectively; Forming a second transparent conductive layer on the green pixel and the white pixel by photo-etching the second transparent conductive layer using the second photosensitive pattern, May include steps.

The first transparent conductive layer and the second transparent conductive layer may have different etching characteristics.

One of the first transparent conductive layer and the second transparent conductive layer may include crystalline ITO and the other may include IZO or amorphous ITO.

The light emitting layer may include a first sub-emission layer that emits red light, a second sub-emission layer that emits blue light, and a second sub-emission layer that emits green light, all of which are disposed on the entire surface of the substrate including the first, second, And a third sub-emission layer on the first sub-emission layer.

And forming a color filter after forming the passivation layer.

By providing a fine resonance structure in the red, green, and blue pixels, light in a narrow wavelength range can be enhanced and light in other wavelength ranges can be suppressed to improve color purity and color reproducibility. Further, by setting the fine resonance length uniquely in the green pixel, the color purity and color reproducibility of the green region can be enhanced.

In addition, the thickness of the pixel electrode of the white pixel can be compensated by including the auxiliary layer, and the auxiliary layer can be formed together with the protective layer, so that the auxiliary layer can be formed without any additional process.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. Like parts are designated with like reference numerals throughout the specification. Whenever a portion of a layer, film, region, plate, or the like is referred to as being "on" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle.

An organic light emitting display according to an embodiment of the present invention will now be described in detail with reference to FIG.

1 is an equivalent circuit diagram of an OLED display according to an embodiment of the present invention.

1, the OLED display includes a plurality of signal lines 121, 171, and 172 and a plurality of pixels PX connected to the plurality of signal lines 121, 171, and 172 and arranged in the form of a matrix. do.

The signal line includes a plurality of gate lines 121 for transmitting gate signals (or scanning signals), a plurality of data lines 171 for transmitting data signals, and a plurality of driving voltage lines 172 for transmitting driving voltages. The gate lines 121 extend substantially in the row direction, are substantially parallel to each other, and the data lines 171 and the driving voltage lines 172 extend in a substantially column direction and are substantially parallel to each other.

Each pixel PX includes a switching thin film transistor Qs, a driving thin film transistor Qd, a storage capacitor Cst, and an organic light emitting diode (LD).

The switching thin film transistor Qs has a control terminal, an input terminal and an output terminal. The control terminal is connected to the gate line 121, the input terminal is connected to the data line 171, And is connected to the transistor Qd. The switching thin film transistor Qs transfers a data signal applied to the data line 171 to the driving thin film transistor Qd in response to a scanning signal applied to the gate line 121. [

The driving thin film transistor Qd also has a control terminal, an input terminal and an output terminal. The control terminal is connected to the switching thin film transistor Qs, the input terminal is connected to the driving voltage line 172, And is connected to the light emitting diode (LD). The driving thin film transistor Qd passes an output current I _LD whose magnitude varies according to the voltage applied between the control terminal and the output terminal.

The capacitor Cst is connected between the control terminal and the input terminal of the driving thin film transistor Qd. The capacitor Cst charges the data signal applied to the control terminal of the driving thin film transistor Qd and maintains the data signal even after the switching thin film transistor Qs is turned off.

The organic light emitting diode LD has an anode connected to the output terminal of the driving thin film transistor Qd and a cathode connected to the common voltage Vss. The organic light emitting diode LD emits light with different intensity according to the output current I _LD of the driving thin film transistor Qd to display an image.

The switching thin film transistor Qs and the driving thin film transistor Qd are n-channel field effect transistors (FETs). However, at least one of the switching thin film transistor Qs and the driving thin film transistor Qd may be a p-channel field effect transistor. Also, the connection relationship between the thin film transistors Qs and Qd, the capacitor Cst, and the organic light emitting diode LD can be changed.

The organic light emitting display shown in FIG. 1 will now be described with reference to FIG.

2 is a plan view schematically showing the arrangement of a plurality of pixels in an organic light emitting display according to an embodiment of the present invention.

2, a red pixel R for displaying red, a green pixel G for displaying green, a blue pixel B for displaying blue, and a blue pixel B for displaying blue are arranged in the OLED display according to an embodiment of the present invention. And white pixels W that do not display white are alternately arranged. The red pixel R, the green pixel G and the blue pixel B are basic pixels for expressing full color, and the brightness can be increased by further including the white pixel W.

Four pixels including a red pixel R, a green pixel G, a blue pixel B, and a white pixel W may be repeated in rows and / or columns in a group. However, the arrangement of the pixels can be variously modified.

The red pixel R, the blue pixel B, and the green pixel G include a microcavity structure, and the white pixel W does not include a fine resonance structure.

The detailed structure of the organic light emitting display shown in FIG. 2 will be described with reference to FIG.

3 is a cross-sectional view illustrating a structure of an OLED display according to an exemplary embodiment of the present invention.

A plurality of thin film transistor arrays are arranged on the insulating substrate 110. The thin film transistor array includes a switching thin film transistor Qs and a driving thin film transistor Qd arranged for each pixel, and they are electrically connected.

A passivation layer 112 is formed on the thin film transistor array. The protective film 112 is formed with a plurality of contact holes (not shown) for exposing a part of the switching thin film transistor Qs and the driving thin film transistor Qd. The protective film 112 may include at least one selected from silicon nitride (SiNx), silicon oxide (SiO ₂₎ and silicon oxynitride (SiON).

A red filter 230R for the red pixel R, a green filter 230G for the green pixel G and a blue filter 230B for the blue pixel B are formed on the protective film 112. The white pixels W , A color filter may not be formed or a transparent white filter (not shown) may be formed. The color filters 230R, 230G, and 230B may be arranged in a color filter on array (CoA) manner.

An overcoat film 180 is formed on the color filters 230R, 230G, and 230B and the protective film 112. [ A plurality of contact holes (not shown) are formed in the overcoat film 180.

Auxiliary layers 188R, 188G, 188B, and 188W are formed on the respective pixels R, G, B, and W on the overcoat film 180. [ Auxiliary layers (188R, 188G, 188B, 188W ) may include at least one selected from silicon nitride (SiNx), silicon oxide (SiO ₂₎ and silicon oxynitride (SiON), comprise the same material as that of the protective film 180, . The auxiliary layers 188R, 188G, 188B, and 188W may have a thickness of about 400 to 1000 ANGSTROM, which is related to the thickness of the pixel electrode 191W of the white pixel W described later.

The pixel electrodes 191R, 191G, 191B, and 191W are formed on the auxiliary layers 188R, 188G, 188B, and 188W. The pixel electrodes 191R, 191G, 191B and 191W are electrically connected to the driving thin film transistor Qd through contact holes (not shown) formed in the protective film 112 and the overcoat film 180, anode.

The lamination structure of the pixel electrodes 191R, 191G, 191B, and 191W of each pixel is different.

The pixel electrode 191R of the red pixel R is a double film including the semitransparent conductive layer 195R and the first transparent conductive layer 196R and the pixel electrode 191B of the blue pixel B is also a double- 195B) and the first transparent conductive layer 196B.

The pixel electrode 191G of the green pixel G is a triple layer film including a semitransparent conductive layer 195G, a first transparent conductive layer 196G, and a second transparent conductive layer 197G.

The pixel electrode 191W of the white pixel W is a single film made of the same material as the second transparent conductive layer 197G of the green pixel G. [

The semi-transparent conductive layers 195R, 195B, and 195G formed on the red pixel R, the blue pixel B, and the green pixel W are made of a material having a property of transmitting a part of light and reflecting a part of light For example, silver (Ag), aluminum (Al), gold (Au), nickel (Ni), magnesium (Mg), and alloys thereof may be formed to a thickness of about 100 to 400 Å. The semi-transparent conductive layers 195R, 195B, and 195G form a fine resonance structure with the common electrode 270, which will be described later.

The first transparent conductive layers 196R, 196B and 196G, the second transparent conductive layer 197G and the pixel electrode 191W of the white pixel W may be made of a transparent conductive oxide such as ITO, IZO and ZnO, The pixel electrode 191W of the second transparent conductive layer 197G and the white pixel W is made of a material having an etching property different from that of the first transparent conductive layer 196R, 196B, or 196G. For example, when the first transparent conductive layers 196R, 196B, and 196G are made of crystalline ITO, the pixel electrode 191W of the second transparent conductive layer 197G and the white pixel W may be made of IZO or ZnO, ITO. ≪ / RTI > This is to prevent the first transparent conductive layers 196R, 196B, and 196G from being etched together in the step of forming the pixel electrode 191W of the second transparent conductive layer 197G and the white pixel W as described later to be.

The thickness of the first transparent conductive layers 196R, 196B, and 196G may be about 100 to 1000 angstroms, and preferably about 100 to 500 angstroms. The thickness of the pixel electrode 191W of the second transparent conductive layer 197G and the white pixel W may also be about 100 to 1000 angstroms and is preferably about 100 to 500 angstroms.

A plurality of insulating members 361 for defining each pixel are formed on the pixel electrodes 191R, 191B, 191G and 191W. On the insulating members 361 and the pixel electrodes 191R, 191B, 191G and 191W An organic light emitting member is formed.

The organic light emitting member may include an organic light emitting layer 370 for emitting light and a sub layer (not shown) for improving the light emitting efficiency of the organic light emitting layer 370.

The organic light emitting layer 370 may include a plurality of sub-light emitting layers (not shown) by sequentially laminating a material that uniquely emits light such as red, green, and blue, and emit white light by combining these colors. At this time, the sub-emission layer may be formed not only vertically but also horizontally, and it may be formed of a combination of various colors instead of red, green and blue as long as it can emit white light.

The sub-layer may be at least one selected from an electron transporting layer, a hole transporting layer, an electron injecting layer, and a hole injecting layer.

A common electrode 270 is formed on the organic light emitting member. The common electrode 270 can be made of a metal having high reflectance and serves as a cathode. The common electrode 270 is formed on the entire surface of the substrate and paired with the pixel electrodes 191R, 191B, 191G, and 191W serving as an anode to flow current to the organic light emitting layer 370. [

As described above, in the embodiment of the present invention, the semi-transparent conductive layers 195R, 195B, and 195G are included in the red pixel (R), the blue pixel (B), and the green pixel (W) .

The micro-resonant structure is one that amplifies light of a specific wavelength by constructive interference by being repeatedly reflected between a reflective layer and a semi-transparent layer where the light is separated by an optical path length. Here, the common electrode 270 serves as a reflective layer, and the semitransparent conductive layers 195R, 195B, and 195G serve as a translucent layer.

The common electrode 270 greatly improves the luminescence characteristics emitted from the organic light emitting layer 370 and the light in the vicinity of the wavelength corresponding to the resonance wavelength of the fine resonance among the modified light is transmitted through the semitransparent conductive layers 195R, And light of other wavelengths is suppressed.

The wavelength range of the light to be enhanced in the fine resonance structure can be determined according to the optical path length, where the optical path length is the distance between the common electrode 270 and the semitransparent conductive layers 195R, 195B and 195G. Therefore, the optical path length of each pixel can be determined by the thickness of the light emitting layer 370 and the pixel electrodes 191R, 191G, and 191B. Since the light emitting layer 370 is formed on the entire surface of the substrate under the same deposition condition, the semitransparent conductive layers 192R, 192B and 192G are also formed on the red pixel R, the green pixel G and the blue pixel B ) Under the same deposition condition and the same photolithography condition, it can be assumed that the thickness is constant for each pixel. Therefore, the optical path length can be adjusted to the thickness of the first transparent conductive layers 196R, 196B, and 196G of the pixel electrodes 191R, 191G, and 191B and the second transparent conductive layer 197G.

  The red pixel R and the blue pixel B have first transparent conductive layers 196R and 196B of about 100 to 1000 ANGSTROM on the semitransparent conductive layers 195R and 195B, On the semitransparent conductive layer 195G, a second transparent conductive layer 197G of about 100 to 1000 ANGSTROM in addition to the first transparent conductive layer 196G of about 100 to 1000 ANGSTROM. The pixel electrode 191G of the green pixel G is thicker than the pixel electrodes 191R and 191B of the red pixel R and the blue pixel B so that the optical path length of the green pixel G can be made larger have.

  This will be described with reference to FIGS. 10 and 11. FIG.

FIG. 10 is a graph showing an emission spectrum of an organic light emitting display according to an embodiment of the present invention, and FIG. 11 is a color coordinate showing color reproducibility of an organic light emitting display according to an embodiment of the present invention.

10, the white light emitted from the light emitting layer 370 has peaks at about 460 nm (blue region), about 530 nm (green region), and about 610 nm (red region) The emission spectrum is shown. Among these, the spectrum of the green region spans a wide wavelength range and overlaps with the spectrum of the long wavelength side of the blue region, and its boundary is unclear. The emission spectrum of the green region is also remarkably low.

When the white light passes through the color filter CF, the green emission spectrum is transmitted through the emission spectrum of the long wavelength side of blue, and the color purity of green is greatly lowered (see 'Green (CF)'). In addition, it can be seen that the color purity of the blue light emission spectrum (Blue (CF)) passing through the blue filter and the red emission spectrum (Red (CF)) passing through the red filter are lower than that of the white light (White). When the color purity is 100% in each wavelength range of white light, the color filter has a lower color purity, and the light passing through the color filter has a color reproducibility equal to or lower than that of the color filter.

In this embodiment, a fine resonance structure is provided for the red pixel R, the blue pixel B and the green pixel G so as to have a high color reproducibility beyond the limit of the color filter itself, It is possible to amplify light in a green wavelength range, especially in a weak peak of the white light emission spectrum, by uniquely setting the fine resonance length of the white light emission spectrum uniquely different from that of the red pixel R and the blue pixel B.

Referring to FIG. 10, a red region (μCavity Red), a green region (μCavity Red), a green region (μCavity Red) and a green region Green) and blue (μCavity Blue), respectively, in a narrow wavelength range. Having a peak in such a narrow wavelength range means that the color purity and color reproducibility have been improved, and the higher light emission intensity means that the light efficiency is improved.

In particular, the green emission spectrum in the narrow wavelength range is set to a unique fine resonance length corresponding to the green wavelength region unlike the red region and the blue region, so that the light in the narrow wavelength region of about 520 to 550 nm is strengthened and the light in the other wavelength region is suppressed . Since the green emission spectrum does not overlap with the longer wavelength side of the blue emission spectrum, the color purity and color reproducibility of green can be improved.

11, when the NTSC region is assumed to be 100% color reproducibility, a structure (R, G, B μCavity + CF) in which fine resonance is formed in the red pixel R, green pixel G and blue pixel B ) Has a high color reproducibility of about 108.5%. It can be seen that the color reproducibility is remarkably improved as compared with the structure in which only the white light emission (Normal White) and the color filter (CF) only have a color reproducibility of about 72% without forming fine resonance have.

On the other hand, since the white pixel W has no fine resonance structure, the light emitted from the light emitting layer passes through the pixel electrode 191W and exits directly to the outside of the substrate. Since the pixel electrode 191W of the white pixel W does not include the transflective conductive layer, the pixel electrodes 191R and 191G of the red pixel R, green pixel G and blue pixel B including the fine resonance structure , 191B). In the embodiment of the present invention, the auxiliary layer 188W may be formed under the pixel electrode 191W of the white pixel W, The optical characteristics of the pixel electrode 191W of the pixel W can be compensated.

The pixel electrodes R, G and B of the red pixel R, the green pixel G and the blue pixel B except for the white pixel W are electrically connected to the transflective conductive layers 195R, 195G and 195B, The first transparent conductive layers 196R, 196G, and 196B, and the second transparent conductive layer 197G are laminated, thereby satisfying the thickness and controlling the optical path length for the fine resonance.

The auxiliary layer 188W may be disposed on the red pixel R, the green pixel G and the blue pixel B in addition to the white pixel W. The auxiliary layer 188W may include a contact hole in the passivation layer 112 Forming step, and therefore can be formed without a separate photolithography step.

A method of manufacturing the OLED display of FIG. 3 will now be described with reference to FIGS. 4 to 9. FIG.

FIGS. 4 to 9 are cross-sectional views sequentially illustrating a method of manufacturing the organic light emitting diode display of FIG. 3 according to an embodiment of the present invention.

Referring to FIG. 4, a plurality of switching thin film transistors Qs and a plurality of driving thin film transistors Qd are formed on an insulating substrate 110. Here, the step of forming the switching thin film transistor Qs and the driving thin film transistor Qd includes a step of laminating and patterning the conductive layer, the insulating layer and the semiconductor layer.

Then, a protective film 112 is formed on the entire surface of the substrate including the plurality of switching thin film transistors Qs and the plurality of driving thin film transistors Qd. The protective film 112 may be formed by chemical vapor deposition (CVD), such as silicon nitride.

Subsequently, color filters 230R, 230G, and 230B are formed on the red, green, and blue pixels R, G, and B, respectively, on the protective film 112, The overcoat film 180 is laminated on the entire surface.

Subsequently, a contact hole (not shown) is formed in the overcoat film 180 at a position overlapping with a part of the driving thin film transistor Qd to expose a part of the protective film 112.

Then, an inorganic insulating film (not shown) made of the same material as that of the protective film 112 is stacked on the overcoat film 180.

Subsequently, the inorganic insulating layer is patterned to form auxiliary layers 188R, 188G, 188B, and 188W located in each pixel. At this time, the protective film 112 exposed through the contact hole of the overcoat film 180 is also patterned to expose the driving thin film transistor Qd located under the protective film 112.

Although the auxiliary layers 188R, 188G, 188B, and 188W and the protective layer 180 are formed by a single photolithography process according to the embodiment of the present invention, A separate photolithographic etching process is not added.

5, a lower conductive layer 190w and an intermediate conductive layer 190x are sequentially stacked on the auxiliary layers 188R, 188G, 188B, and 188W and the overcoat film 180. [ The lower conductive layer 190w may be made of Ag, Al, Au, Ni, Mg, or an alloy thereof to a thickness of about 100 to 400 Å And the intermediate conductive layer 190x can be formed by depositing ITO at about 200 to 400 ° C.

Next, a first photoresist pattern (not shown) is applied on the intermediate conductive layer 190x and patterned to form a first photoresist pattern 85a on the red pixel R, the blue pixel B, and the green pixel G.

6, a red pixel R, a green pixel G and a blue pixel B are sequentially formed by sequentially etching the intermediate conductive layer 190x and the lower conductive layer 190w by using the first photosensitive pattern 85a. And the first transparent conductive layers 196R, 196B, and 196G are formed on the transparent conductive layers 195R, 195B, and 195G, respectively.

The translucent conductive layer 195R and the first transparent conductive layer 196R of the red pixel R constitute the pixel electrode 191R of the red pixel R and the semitransparent conductive layer 195B of the blue pixel B and the semi- One transparent conductive layer 196B constitutes the pixel electrode 191B of the blue pixel B.

7, an upper conductive layer 190y is formed on the entire surface of the substrate. The upper conductive layer 190y can be formed by depositing ITO in an amorphous state by depositing ITO at a relatively low temperature of about 20 to 150 ° C, preferably at room temperature, or by depositing IZO.

Next, a second photoresist pattern (not shown) is coated on the upper conductive layer 190y and patterned to form a second photoresist pattern 95a on the green pixel G and the white pixel W.

Referring to FIG. 8, a second transparent conductive layer 197G is formed on the green pixel G by etching the upper conductive layer 190y using the second photosensitive pattern 95a, and a second transparent conductive layer 197G is formed on the white pixel W, Thereby forming the electrode 191W.

The semitransparent conductive layer 195G of the green pixel G, the first transparent conductive layer 196G and the second transparent conductive layer 197G constitute the pixel electrode 191G of the green pixel G. [

 9, an insulating film (not shown) is coated on the pixel electrodes 191R, 191G, 191B, and 191W and the overcoat film 180 and patterned to form a pixel electrode 191R, 191G, 191B, A plurality of insulating members 361 are formed.

Next, a light emitting layer 370 is formed by sequentially laminating a red light emitting layer (not shown), a blue light emitting layer (not shown) and a green light emitting layer (not shown) on the entire surface of the substrate.

Next, a common electrode 270 is formed on the light emitting layer 370.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, And falls within the scope of the invention.

1 is an equivalent circuit diagram of an OLED display according to an embodiment of the present invention,

2 is a plan view schematically showing the arrangement of a plurality of pixels in an organic light emitting display according to an embodiment of the present invention,

3 is a cross-sectional view illustrating a structure of an OLED display device according to an exemplary embodiment of the present invention,

FIGS. 4 to 9 are cross-sectional views sequentially illustrating a method of manufacturing the organic light emitting diode display of FIG. 3 according to an embodiment of the present invention,

10 is a graph showing an emission spectrum of an organic light emitting display according to an embodiment of the present invention,

11 is a color coordinate showing the color reproducibility of the OLED display according to an embodiment of the present invention.

Claims (18)

A first pixel, a second pixel, and a third pixel that display different colors and a fourth pixel that does not display a color, The first, second, third, and fourth pixels are The first electrode, A second electrode facing the first electrode, A light emitting layer positioned between the first electrode and the second electrode, An auxiliary layer disposed below the first electrode and including an insulating material, A thin film transistor electrically connected to the first electrode, and A protective film formed between the thin film transistor and the first electrode, / RTI > The first electrode of the first pixel and the first electrode of the second pixel A first transparent conductive layer, and A semi-transparent conductive layer which is located between the auxiliary layer and the first transparent conductive layer and forms a fine resonance with the second electrode, / RTI > The first electrode of the third pixel The first transparent conductive layer, A semi-transparent conductive layer which is located between the auxiliary layer and the first transparent conductive layer and forms a fine resonance with the second electrode, and A second transparent conductive layer formed on the first transparent conductive layer and having an etch rate different from that of the first transparent conductive layer, / RTI > The first electrode of the fourth pixel is made of the same material as the second transparent conductive layer, Wherein the protective layer and the auxiliary layer comprise the same material. delete delete The method of claim 1, The OLED display device of the protection layer and the auxiliary layer contains at least one selected from silicon nitride (SiNx), silicon oxide (SiO ₂₎ and silicon oxynitride (SiON). The method of claim 1, Wherein the sum of thicknesses of the auxiliary layer and the first electrode of the fourth pixel is 500 to 2000 ANGSTROM. The method of claim 1, Wherein one of the first transparent conductive layer and the second transparent conductive layer includes crystalline ITO and the other includes ITO formed from IZO or an amorphous state. The method of claim 1, Wherein the first pixel is a red pixel, the second pixel is a blue pixel, and the third pixel is a green pixel. The method of claim 1, The light- And a plurality of sub-emission layers for emitting light of different wavelengths, The lights of different wavelengths are combined to emit white light Organic light emitting display. 9. The method of claim 8, Wherein the first pixel, the second pixel, and the third pixel each further include a color filter formed under the first electrode. In a method of manufacturing an organic light emitting display device including a red pixel, a blue pixel, a green pixel, and a white pixel, Forming a thin film transistor on the substrate, Forming a protective film on the thin film transistor, Forming an auxiliary layer on the protective film, Forming a plurality of contact holes for exposing the thin film transistor on the passivation layer by patterning the passivation layer and the auxiliary layer, and forming an auxiliary layer for each pixel; Forming a first electrode on an auxiliary layer located in each pixel, Forming a light emitting layer on the first electrode, and Forming a second electrode on the light emitting layer Lt; / RTI > The step of forming the first electrode Forming a semitransparent conductive layer over the auxiliary layer of the red, green and blue pixels, respectively, Forming a first transparent conductive layer on the semitransparent conductive layer of the red, green, and blue pixels, respectively, and Forming a second transparent conductive layer on each of the first transparent conductive layer of the green pixel and the auxiliary layer of the white pixel, Wherein the organic light emitting display device further comprises: delete delete 11. The method of claim 10, Wherein the first transparent conductive layer and the second transparent conductive layer have different etching properties. The method of claim 13, Wherein one of the first transparent conductive layer and the second transparent conductive layer includes crystalline ITO and the other includes IZO or amorphous ITO. 11. The method of claim 10, The step of forming the light emitting layer A first sub-emission layer that emits red light, a second sub-emission layer that emits blue light, and a third sub-emission layer that emits green light are sequentially disposed on the entire surface of the substrate including the first, second, third, and fourth pixels And laminating the organic light emitting display device. 16. The method of claim 15, And forming a color filter after forming the passivation layer. The method of claim 1, Wherein an optical path length of the third pixel is different from an optical path length of the first pixel and the second pixel. The method of claim 17, Wherein an optical path length of the third pixel is longer than an optical path length of the first pixel and the second pixel.

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