KR102389345B1 - Organic emitting light display device - Google Patents

Abstract

The present invention relates to an organic light emitting display device capable of improving light extraction efficiency and color reproducibility.
The organic light emitting display device according to the present invention relieves and/or removes the step difference of the color filter layer by providing a step difference to the insulating layer located below the color filter layer, and at the same time improves the luminance of light extracted through the red, green and blue color filters. it is possible to do

Description

Organic light emitting display device {ORGANIC EMITTING LIGHT DISPLAY DEVICE}

The present invention relates to an organic light emitting display device capable of improving light extraction efficiency and color reproducibility.

Recently, a flat panel display device having excellent characteristics such as reduction in thickness, weight reduction, and low power consumption has been widely developed and applied to various fields.

Among flat panel display devices, an organic light emitting display device, also called an organic electroluminescent display device or an organic electroluminescent display device, injects electric charges into a light emitting layer provided between a cathode, which is an electron injection electrode, and an anode, which is a hole injection electrode, so that electrons and holes are paired. A light emitting device that emits light while extinguishing is used.

Such an organic light emitting display device can be implemented on a flexible substrate such as plastic, and has advantages such as a high contrast ratio because it is a self-luminous type.

In an organic light emitting display device proposed at an early stage, one pixel includes red, green, and blue sub-pixels, and each of the red, green, and blue sub-pixels includes an organic light emitting layer emitting red, green, and blue light, respectively. By including, the image is displayed by combining the light emitted from each sub-pixel.

However, since the organic emission layers emitting light of different colors are formed of different materials, there is a problem that not only have different luminous efficiencies, but also the lifetime of each sub-pixel is different.

Accordingly, in recent years, an organic light emitting display device in which light emitted from an organic light emitting layer passes through a color filter to display light of different colors has been proposed.

1 schematically shows a cross-section of a conventional organic light emitting display device to which a color filter is applied. For reference, the organic light emitting display device illustrated in FIG. 1 is a bottom emission type display device.

Referring to FIG. 1 , a conventional organic light emitting display device 10 includes a substrate 110 on which a thin film transistor and various circuits are mounted, and an organic light emitting device 150 disposed on the substrate 110 .

The organic light emitting device 150 includes a first electrode 151 conducting with the thin film transistor of the substrate 110 , an organic light emitting layer 152 emitting white light, and a second electrode 153 .

The insulating layer 120 and the planarization layer 140 are provided between the substrate 110 and the organic light emitting device 150 , and the color filter layer 130 is positioned between the insulating layer 120 and the planarization layer 140 .

The color filter layer 130 includes a red color filter, a green color filter, and a blue color filter respectively corresponding to the red, green, and blue sub-pixels. Accordingly, the white light emitted from the organic emission layer 152 passes through the red color filter, the green color filter, or the blue color filter to display red, green, or blue light.

At this time, for example, as white light emitted from the organic light emitting layer 152 passes through the color filter layer 130 and light of a specific wavelength band is absorbed, the color filter layer 130 compared to the actual white light emitted from the organic light emitting layer 152 The extraction efficiency of the light emitted through it is inevitably reduced.

For example, since the red color filter 17a emitting relatively long-wavelength light absorbs short-wavelength light from white light emitted from the organic light-emitting layer 152 and selectively emits only long-wavelength light, the actual organic light-emitting layer 152 The extraction efficiency of the red light emitted through the red color filter compared to the white light emitted from the is reduced.

Recently, an attempt has been made to increase the content of a colorant contained in the color filter layer 130 in order to further improve the color reproducibility of light emitted through the color filter layer.

When only the content of the colorant contained in the color filter layer 130 is increased and the thickness of the color filter layer 130 is maintained the same as before, the extraction efficiency of light passing through the color filter layer 130 is significantly reduced, so the content of the colorant is increased. At the same time, the thickness of the color filter layer 130 should be thick.

At this time, since the content of the colorant contained in the red color filter, the green color filter, and the blue color filter required for realization of high color reproducibility is different, each color forming the color filter layer 130 as shown in FIG. 2 . The thickness of the filter is bound to be different.

In this case, the upper surface of the planarization layer 140 positioned on the color filter layer 130 due to the step difference generated by the height difference between the red color filter 131 , the green color filter 132 , and the blue color filter 133 . Also, a step may be formed. In addition, the step formed on the planarization layer 140 also forms a step difference between the first electrode 151 and the second electrode 153 , so that the first electrode 151 and/or the second electrode 153 is shorted. may cause the phenomenon to be

The present invention is to solve the above problems, and the present invention alleviates the step formed by the red, green and blue color filters having different thicknesses without the need to interpose a separate layer for compensating for the step difference of the color filter layer. It is an object of the present invention to provide an organic light emitting display device capable of reducing the possibility that the organic light emitting device is short-circuited by removing and/or removing the organic light emitting diode.

In addition, the present invention provides an organic layer capable of alleviating and/or removing the step difference of the color filter layer and improving the luminance of light extracted through the red, green, and blue color filters by giving a step to the insulating layer located below the color filter layer. An object of the present invention is to provide a light emitting display device.

According to one aspect of the present invention for solving the above technical problem, the thickness difference between the red color filter, the green color filter, and the blue color filter is compensated for by the step difference of the insulating layer, thereby preventing the short circuit of the organic light emitting device located on the color filter layer. An organic light emitting display device is provided.

In addition, according to another aspect of the present invention, the thickness difference between the red color filter, the green color filter, and the blue color filter is compensated by a plurality of insulating films stacked to form a step upward toward the organic light emitting device positioned on the color filter layer. An organic light emitting display device for preventing short circuit is provided

In addition, according to the present invention, the thickness of the insulating layer or the plurality of insulating layers positioned under the color filter layer is determined in consideration of transmittance for each spectrum according to the thickness of the insulating layer or the plurality of insulating layers, so that the insulating layer or the plurality of insulating layers is colored. An organic light emitting display device in which the brightness of light extracted through the color filter layer is improved while compensating for the step difference of the filter layer may be provided.

According to the present invention, it is possible to alleviate and/or remove the step difference formed by the red, green, and blue color filters having different thicknesses without the need to interpose a separate layer for compensating for the step difference of the color filter layer. Accordingly, the possibility that the organic light emitting diode positioned on the color filter layer may be short-circuited may be reduced.

In addition, according to the present invention, the transmittance of each spectrum according to the thickness of the insulating layer or the plurality of insulating layers compensating for the step difference of the color filter layer is matched with the spectrum of the light extracted through the color filter layer to further increase the luminance of the light extracted through the color filter layer. can be improved

1 schematically shows a cross-section of a conventional organic light emitting display device to which a color filter is applied.
FIG. 2 is an enlarged view of region X of FIG. 1 .
3 schematically illustrates a cross-section of an organic light emitting display device according to an embodiment of the present invention.
FIG. 4 is an enlarged view of region X of FIG. 3 .
5 is a graph showing transmittance for each spectrum according to the thickness of the insulating layer.
6 is a schematic cross-sectional view of an organic light emitting display device according to another exemplary embodiment of the present invention.
FIG. 7 is an enlarged view of region X of FIG. 6 .

Hereinafter, an organic light emitting display device according to various aspects of the present invention will be described in detail.

In general, an organic light emitting display device may be divided into a top emission type and a bottom emission type according to an emission direction of light.

3 is a schematic cross-sectional view of a bottom emission type organic light emitting display device according to an embodiment of the present invention. In particular, FIG. 3 shows a region corresponding to one pixel, and one pixel includes regions corresponding to red, green, and blue sub-pixels.

Referring to FIG. 3 , in the organic light emitting display device according to an embodiment of the present invention, the thickness difference between the red color filter, the green color filter, and the blue color filter is compensated for by the step difference of the insulating layer, so that the organic light emitting diode is positioned on the color filter layer. to prevent short circuit.

More specifically, the organic light emitting display apparatus 200 includes a substrate 210 on which a thin film transistor and various circuits are mounted, and an organic light emitting device 270 disposed on the substrate 210 .

The substrate 210 may be a substrate made of a material such as glass or plastic. In particular, in the bottom emission type organic light emitting display device, the substrate 210 is a substrate through which light passing through the color filter layer 250 is emitted to the outside, and is preferably made of a transparent material.

In addition, the substrate 210 is a thin film transistor substrate, and the thin film transistor 220 is provided on the inner surface of the substrate 210 facing the organic light emitting device 270 .

Specifically, the gate electrode 221 is positioned on the substrate 210 , and the gate insulating layer 231 is disposed on the substrate 210 and the gate electrode 221 to insulate the gate electrode 221 and the active layer 222 . this is located

In addition, an active layer 222 and an etch stopper 232 are positioned on the gate insulating layer 231 , and a source electrode 223 and a drain electrode are disposed on the active layer 222 and the etch stopper 232 . (224) is located.

The source electrode 223 and the drain electrode 224 are electrically connected to the active layer 222 in a manner in contact with the active layer 222 , and occupy a partial area on the etch stopper 232 .

In this specification, only the driving thin film transistor among various thin film transistors that may be included in the organic light emitting diode display 200 is illustrated for convenience of description. In addition, although the thin film transistor 220 is described as having an inverted staggered structure in this specification, a thin film transistor having a coplanar structure may also be used.

Next, the insulating layer 240 is positioned on the thin film transistor 220 , and the color filter layer 250 is positioned on the insulating layer 240 . The color filter layer 250 is a layer for converting the color of white light emitted from the organic emission layer 272 , and may include a red color filter, a green color filter, and a blue color filter. Here, the red color filter, the green color filter, and the blue color filter are located in regions corresponding to the red, green, and blue sub-pixels, respectively.

In addition, the color filter layer 250 is positioned on the insulating layer 240 in a region corresponding to the emission region. Here, the emission region may mean a region in which the organic emission layer 272 emits light.

A planarization layer 260 is positioned on the insulating layer 240 and the color filter layer 250 . The planarization layer 260 relieves and/or removes the step difference between the insulating layer 240 and the color filter layer 250 to form a flat upper surface of the organic light emitting device 270 provided on the planarization layer 260 . It serves to prevent short circuit of the first electrode 271 and/or the second electrode 273 .

The planarization layer 260 is, for example, an acrylic resin, a phenol resin, a polyimide-based resin, a polyamide-based resin, an unsaturated polyester-based resin, a polyphenylene-based resin, a polyphenylene sulfide-based resin, benzocyclobutene, or a photoresist. It may be formed of the same material.

An organic light emitting diode 270 emitting white light and a bank layer 233 partitioning a light emitting area are positioned on the planarization layer 260 .

Here, the organic light emitting device 270 is positioned on the planarization layer 260 , is positioned on the first electrode 271 electrically connected to the thin film transistor 220 , and the first electrode 120 , and emits white light. and an organic light emitting layer 272 and a second electrode 273 as a reflective cathode positioned on the organic light emitting layer 272 .

The first electrode 271 is preferably formed of a transparent conductive oxide so that light emitted from the organic emission layer 272 can be emitted downward. As a material of the first electrode 271 , the transparent conductive oxide includes indium tin oxide (ITO), indium zinc oxide (IZO), aluminum zinc oxide (AZO), gallium doped zinc oxide (GZO), zinc tin oxide (ZTO), and GTO. (Gallium Tin Oxide) or FTO (Fluorine doped Tin Oxide).

Meanwhile, the second electrode 273 may include Mo, MoW, Cr, Ag, APC (Ag-Pd-Cu alloy), Al or Al alloy to reflect the light emitted from the organic light emitting layer 272 downward. It may be formed of a reflective metal or an alloy thereof. Alternatively, a reflective film formed of a reflective metal or an alloy thereof may be provided on a transparent conductive oxide.

The organic emission layer 272 may include a hole transport layer, a hole injection layer, a light emitting material layer, an electron injection layer, and an electron transport layer from an upper portion of the first electrode 271 .

Referring to FIG. 4 which is an enlarged view of region X of FIG. 3 , the color filter layer 250 of the organic light emitting display device 200 according to an embodiment of the present invention includes a red color filter 251 and a green color filter having different thicknesses. It includes a color filter 252 and a blue color filter 253 .

In this case, the thickness d1 of the red color filter 251 may be greater than the thickness d2 of the green color filter 252 and the thickness d3 of the blue color filter 253 . Also, the thickness of the green color filter 252 may be greater than the thickness of the blue color filter 253 .

This difference in thickness of the color filters may be due to a difference in the content of a colorant contained in the color filters to realize the characteristics of each color filter.

That is, the content of the colorant contained in the red color filter 251 having a thickness greater than that of the green color filter 252 and the blue color filter 253 is contained in the green color filter 252 and the blue color filter 253 . It may be more than the content of the colorant used.

At this time, the thickness of the red color filter 251 is substantially the same as or similar to that of the green color filter 252 and the blue color filter 253 , but when only the content of the colorant is increased, the thickness of the red color filter 251 is As the density of the colorant increases, there is a fear that the light extraction efficiency through the red color filter 251 is significantly reduced.

Accordingly, the color reproducibility of the light passing through the color filter can be improved in consideration of the color characteristics of the colorant by forming the color filters to have different thicknesses while the density of the colorant in the color filter is similar.

In the case of most of the red colorants known so far, it is preferable to provide a color filter having a high content of the red colorant compared to the green colorant and the blue colorant in order to realize a high color reproducibility because the color reproducibility is low compared to the green colorant and the blue colorant.

Accordingly, the color filter layer 250 of the organic light emitting display device 200 according to an embodiment of the present invention includes a red color filter 251 , a green color filter 252 , and a blue color filter 253 having different thicknesses. However, the thickness of the red color filter 251 is greater than that of the other color filters.

Also, for a similar reason, the green color filter 252 may be formed to be thicker than the blue color filter 253 , and the content of the colorant contained in the green color filter 252 is determined by the content of the colorant contained in the blue color filter 253 . can be more

In general, the planarization layer 260 or the step difference compensation layer provided separately from the planarization layer 260 alleviates and/or removes the step difference between the insulating layer 240 and the color filter layer 250 to form a flat upper surface. can be provided. Also, the step compensation layer may be provided to compensate for a height difference between upper surfaces of the red color filter 251 , the green color filter 252 , and the blue color filter 253 included in the color filter layer 250 .

However, when the planarization layer 260 is simply used, it is possible to compensate for the thickness difference between the red color filter 251 , the green color filter 252 , and the blue color filter 253 included in the color filter layer 250 . , the planarization layer 260 has no effect on the luminance of light extracted through the color filter layer 250 .

Accordingly, according to the present invention, the red color filter 251 , the green color filter 252 , and the blue color filter included in the color filter layer 250 through the insulating layer 240 positioned below the color filter layer 250 . While compensating for the thickness difference between the layers 253 , the transmittance for each spectrum according to the thickness of the insulating layer 240 is matched with the spectrum of the light extracted through the color filter layer 250 . Brightness can be further improved.

To this end, the thickness h1 of the insulating layer 240 positioned under the red color filter 251 is the thickness h2 of the insulating layer 240 positioned under the green color filter 252 and the blue color filter. It may be smaller than the thickness h3 of the insulating layer 240 positioned below the 253 . As described above, the red color filter 251 , the green color filter 252 , and the blue color filter 253 included in the color filter layer 250 by varying the thickness of the insulating layer 240 according to the type of color filter positioned thereon. ), it is possible to mitigate and/or eliminate the thickness difference between them.

Here, the insulating layer 240 may be formed of a material such as SiO ₂ , SiN _x and/or SiO _x N _y , and preferably a SiO ₂ insulating layer. The thickness difference of the above-described insulating layer 240 may be provided by etching performed so that the insulating layer has different heights depending on the type of the color filter positioned thereon after forming a single insulating layer.

5 is a graph showing transmittance for each spectrum according to the thickness of the SiO ₂ insulating layer.

Referring to FIG. 5 , the insulating layer 240 exhibits different transmittances depending on the spectrum, and the change in transmittance varies according to the thickness of the insulating layer.

Accordingly, when the thickness of the insulating layer 240 is changed in consideration of the spectrum of light extracted through the color filter positioned on the insulating layer 240 , it is possible to further improve the luminance of the light extracted through the color filter. .

For example, when the insulating layer 240 has a high transmittance at 550 nm to 650 nm, the red light passing through the red color filter 251 through matching with the red color filter 251 is transmitted by the insulating layer 240 . By reducing the possibility of absorption, it is possible to further improve the luminance of red light as a result.

Tables 1 to 3 below show the lower portions of the red color filter 251 , the green color filter 252 , and the blue color filter 253 having different thicknesses.

The values indicate color coordinates and luminance characteristics according to the thickness of the SiO ₂ insulating layer 240 .

Thickness (㎛) SiO ₂ thickness color coordinates luminance red color filter (Å) x y Y 3.1 1000 0.677 0.319 0.80 2000 0.677 0.319 0.91 3000 0.677 0.319 0.81 4000 0.677 0.319 0.90 5000 0.677 0.318 0.82 6000 0.676 0.320 0.88 7000 0.678 0.318 0.84 8000 0.676 0.320 0.86 9000 0.678 0.318 0.85 10000 0.676 0.320 0.85

Thickness (㎛) SiO ₂ thickness color coordinates luminance green color filter (Å) x y Y 2.5 1000 0.263 0.663 2.96 2000 0.265 0.664 3.36 3000 0.261 0.663 3.02 4000 0.268 0.663 3.28 5000 0.258 0.664 3.10 6000 0.270 0.661 3.19 7000 0.257 0.666 3.18 8000 0.269 0.659 3.13 9000 0.259 0.668 3.22 10000 0.267 0.658 3.11

Thickness (㎛) SiO ₂ thickness color coordinates luminance blue color filter (Å) x y Y 2.4 1000 0.143 0.049 0.55 2000 0.142 0.051 0.58 3000 0.143 0.048 0.59 4000 0.143 0.050 0.55 5000 0.142 0.051 0.60 6000 0.143 0.048 0.57 7000 0.142 0.051 0.56 8000 0.142 0.049 0.59 9000 0.143 0.049 0.57 10000 0.142 0.051 0.58

Insulation in consideration of the color coordinates and luminance characteristics of the red color filter 251 , the green color filter 252 , and the blue color filter 253 according to the thickness of the SiO ₂ insulating layer 240 shown in Tables 1 to 3 above The step of the layer 240 may be designed as shown in the following table.

division Thickness (㎛) luminance step
(μm) item Red green blue Red green blue design 1 color filter 3.1 2.5 2.4 0.90
(ref) 3.28
(ref) 0.55
(ref) 0.7 insulating layer 0.4 0.4 0.4 total thickness 3.5 2.9 2.8 design 2 color filter 3.1 2.5 2.4 0.91
(1.4%) 3.36
(2.6%) 0.60
(8.4%) 0.6 insulating layer 0.2 0.2 0.5 total thickness 3.3 2.7 2.9 design 3 color filter 3.1 2.5 2.4 0.80
(-11.1%) 3.18
(-3.1%) 0.59
(7.9%) 0 insulating layer 0.1 0.7 0.8 total thickness 3.2 3.2 3.2 design 4 color filter 3.1 2.5 2.4 0.91
(1.4%) 3.13
(-4.4%) 0.57
(2.9%) 0 insulating layer 0.2 0.8 0.9 total thickness 3.3 3.3 3.3 design 5 color filter 3.1 2.5 2.4 0.81
(-10.3%) 3.22
(-1.9%) 0.58
(4.7%) 0 insulating layer 0.3 0.9 One total thickness 3.4 3.4 3.4 design 6 color filter 3.1 2.5 2.4 0.90
(0.0%) 3.22
(-1.9%) 0.59
(7.9%) 0.3 insulating layer 0.4 0.9 0.8 total thickness 3.5 3.4 3.2

Referring to Design 1 of Table 4, the red color filter 251, the green color filter 252, and the blue color filter 253 have different thicknesses, and the insulating layer 240 is positioned under each color filter. The thickness was designed to be the same as 0.4 μm.

As a result, the step difference of the upper surfaces of the red color filter 251 , the green color filter 252 , and the blue color filter 253 is 7,000 Å at most, which is provided on the planarization layer 260 as well as the planarization layer 260 . A level difference at which a short circuit occurs exists in the first electrode 271 and/or the second electrode 273 of the organic light emitting device 270 .

In Design 2, the thickness of the color filter is the same as that of Design 1, but compared to Design 1, the thickness of the insulating layer 240 positioned under the red color filter 251 and the green color filter 252 is 0.2 μm. , the thickness of the insulating layer 240 positioned under the blue color filter 253 was designed to be 0.5 μm.

As a result, compared to Design 1, the luminance of light passing through the red color filter 251, the green color filter 252, and the blue color filter 253 increased, but the red color filter 251, the green color filter 252 and It can be seen that the step difference of the upper surface of the blue color filter 253 is up to 6,000 Å.

Meanwhile, in the case of designs 3 to 5, the sum of the thicknesses of the red color filter 251 and the insulating layer 240 positioned below the red color filter 251 , the green color filter 252 and the green color filter 252 . ) so that the sum of the thicknesses of the insulating layer 240 positioned under the blue color filter 253 and the insulating layer 240 positioned under the blue color filter 253 is equal to the sum of the thicknesses of the insulating layer 240 . ) was designed.

As a result, in the case of Design 3, which is designed so that the sum of the thicknesses of the color filter and the insulating layer 240 is 3.2 μm, and Design 5, which is designed to be 3.4 μm, the red color having different thicknesses due to the insulating layer 240 . Although the step difference between the color filter 251 , the green color filter 252 , and the blue color filter 253 is completely removed, it can be seen that the luminance of the red light passing through the red color filter 251 is reduced by about 10%.

On the other hand, in the case of Design 4, which is designed so that the sum of the thicknesses of the color filter and the insulating layer 240 is 3.3 μm, the luminance of green light passing through the green color filter 252 is decreased by about 4%, but the red color filter ( It can be seen that the luminance of the red light passing through 251 and the blue light passing through the blue color filter 253 are increased.

Also, in the case of Design 6, in which the step difference between the upper surfaces of the red color filter 251 , the green color filter 252 , and the blue color filter 253 is 3,000 Å at most, the green light passing through the green color filter 252 . The luminance of the red light passing through the red color filter 251 and the luminance of the blue light passing through the blue color filter 253 may be similar to or increased to other design values while minimizing the decrease in luminance.

Based on the results of Design 4 and Design 6, according to the present invention, the step difference of the color filter layer 250 is alleviated by the insulating layer 240 having a different height depending on the type of the color filter positioned thereon. and/or at the same time as removing, the transmittance of each spectrum according to the thickness of the insulating layer and the spectrum of the light extracted through the color filter layer may be matched to further improve the luminance of the light extracted through the color filter layer.

Accordingly, according to the present invention, the insulating layer 240 provided with a step difference to have a different height depending on the type of color filter positioned thereon is a red color filter 251 , a green color filter 252 , and a blue color filter. A short circuit is prevented in the first electrode 271 and/or the second electrode 273 of the organic light emitting device 270 positioned on the color filter layer 250 by setting the step of the upper surface of the 253 to be 4,000 Å or less. can be prevented from occurring.

6 is a schematic cross-sectional view of an organic light emitting display device according to another exemplary embodiment of the present invention.

Referring to FIG. 6 , in the organic light emitting display device according to another embodiment of the present invention, the difference in thickness between the red color filter, the green color filter, and the blue color filter is compensated for by a plurality of insulating layers stacked to form a step toward the top, thereby providing color. It is provided to prevent a short circuit of the organic light emitting device positioned on the filter layer.

More specifically, the organic light emitting display device 300 includes a substrate 310 on which a thin film transistor and various circuits are mounted, and an organic light emitting device 370 disposed on the substrate 310 . In addition, the substrate 310 is a thin film transistor substrate, and the thin film transistor 320 is provided on the inner surface of the substrate 310 facing the organic light emitting device 370 .

Specifically, a gate electrode 321 is positioned on the substrate 310 , and a gate insulating layer 331 is disposed on the substrate 310 and the gate electrode 321 to insulate the gate electrode 321 and the active layer 322 . this is located

In addition, an active layer 322 and an etch stopper 332 are positioned on the gate insulating layer 331 , and a source electrode 323 and a drain electrode 324 are disposed on the active layer 322 and the etch stopper 332 . this is located

Next, the insulating layer 340 is positioned on the thin film transistor 320 , and the color filter layer 350 is positioned on the insulating layer 340 . A planarization layer 360 is positioned on the insulating layer 340 and the color filter layer 350 . The planarization layer 360 relieves and/or removes the step difference between the insulating layer 340 and the color filter layer 350 to form a flat upper surface, thereby forming a first step of the organic light emitting device 370 provided on the planarization layer 360 . It serves to prevent short circuit of the first electrode 371 and/or the second electrode 373 .

An organic light emitting diode 370 emitting white light and a bank layer 333 partitioning a light emitting area are positioned on the planarization layer 360 . The organic light emitting device 370 is disposed on the planarization layer 360 , is disposed on the first electrode 371 electrically connected to the thin film transistor 320 , and the first electrode 320 , and emits white light. It includes an emission layer 372 and a second electrode 373 positioned on the organic emission layer 372 .

Referring to FIG. 7 which is an enlarged view of region X of FIG. 6 , the color filter layer 350 includes a red color filter 351 , a green color filter 352 , and a blue color filter 353 having different thicknesses. , the thickness difference between the red color filter 351 , the green color filter 352 , and the blue color filter 353 may be compensated for by the plurality of insulating layers 341 , 342 , 343 stacked to form a step toward the top. .

To this end, the first insulating layer 341 constituting the lowermost layer of the insulating layer 340 is in contact with the red color filter 351 , is located on the first insulating layer 341 , and has a smaller area than the first insulating layer 341 . The second insulating film 342 that forms a step with the first insulating film 341 by having it is in contact with the green color filter 352 . In addition, the third insulating layer 343 disposed on the second insulating layer 342 and having a smaller area than the second insulating layer 342 and forming a step with the second insulating layer 342 is a blue color filter 353 . come into contact with

In this embodiment, the luminance of the red light extracted through the red color filter 351 is improved by matching the spectrum of the red light extracted through the red color filter 351 and the transmittance for each spectrum according to the thickness of the first insulating film 341 . can do it

In addition, in the case of the green color filter 352 or the blue color filter 353, the sum of the spectrum of green light or blue light extracted through this and the thickness of the first insulating film 341 and the second insulating film 342 or the first insulating film ( 341 ), the transmittance of each spectrum according to the sum of the thicknesses of the second insulating film 342 and the third insulating film 343 , and the luminance of green light or blue light extracted through the green color filter 352 or the blue color filter 353 . can improve

Accordingly, according to the present invention, the step difference of the color filter layer 350 is alleviated and/or removed by the plurality of insulating layers 341 , 342 , 343 stacked to have different heights depending on the type of color filter positioned thereon. At the same time, by matching the transmittance for each spectrum according to the thickness of the stacked insulating film and the spectrum of the light extracted through the color filter layer, the luminance of the light extracted through the color filter layer can be further improved.

In addition, the plurality of insulating layers 341 , 342 , and 343 stacked to have different heights depending on the type of color filter positioned thereon is a red color filter 351 , a green color filter 352 , and a blue color filter 353 . By setting the step difference of the upper surface of the to be 4,000 Å or less, the occurrence of a short circuit in the first electrode 371 and/or the second electrode 373 of the organic light emitting device 370 positioned above the color filter layer 350 is prevented. can be prevented

In the above, although the embodiment of the present invention has been mainly described, various changes or modifications may be made at the level of those skilled in the art. Accordingly, it will be understood that such changes and modifications are included within the scope of the present invention without departing from the scope of the present invention.

Claims (9)

Board;
an insulating layer positioned on the substrate and having a step formed thereon;
a color filter layer including a red color filter, a green color filter, and a blue color filter disposed on the substrate;
a planarization layer disposed on the color filter layer;
an organic light emitting device positioned on the planarization layer;
includes,
The thicknesses of the red color filter, the green color filter, and the blue color filter are different from each other, and the thickness difference between the red color filter, the green color filter and the blue color filter is compensated for by the step difference of the insulating layer.
Organic light emitting display device.
According to claim 1,
The thickness of the red color filter is greater than the thickness of the green color filter and the blue color filter,
Organic light emitting display device.
According to claim 1,
The content of the colorant contained in the red color filter is greater than the content of the colorant contained in the green color filter and the blue color filter,
Organic light emitting display device.
According to claim 1,
The step difference between the upper surfaces of the red color filter, the green color filter and the blue color filter is 4,000 Å or less,
Organic light emitting display device.
According to claim 1,
The thickness of the insulating layer positioned under the red color filter is smaller than the thickness of the insulating layer positioned under the green color filter and the blue color filter;
Organic light emitting display device.
Board;
an insulating layer positioned on the substrate and having a step formed thereon;
a color filter layer including a red color filter, a green color filter, and a blue color filter disposed on the substrate;
a planarization layer disposed on the color filter layer;
an organic light emitting device positioned on the planarization layer;
including,
The insulating layer is composed of a plurality of insulating films stacked to form a step toward the top,
The thicknesses of the red color filter, the green color filter, and the blue color filter are different from each other, and the thickness difference between the red color filter, the green color filter, and the blue color filter is compensated for by a step formed by the plurality of insulating layers. ,
Organic light emitting display device.
7. The method of claim 6,
The plurality of insulating films,
a first insulating film positioned on the substrate;
a second insulating layer disposed on the first insulating layer and having a smaller area than the first insulating layer;
a third insulating layer disposed on the second insulating layer and having a smaller area than the second insulating layer;
containing,
Organic light emitting display device.
8. The method of claim 7,
The red color filter is in contact with the first insulating film,
The green color filter is in contact with the second insulating film,
The blue color filter is in contact with the third insulating film,
Organic light emitting display device.
7. The method of claim 6,
The step difference between the upper surfaces of the red color filter, the green color filter and the blue color filter is 4,000 Å or less,
Organic light emitting display device.

Images