KR102089331B1 - Organic light emitting display - Google Patents

Abstract

The present invention is to provide an organic light emitting display device capable of improving the life.
The organic light emitting diode display according to the present invention includes first and second electrodes facing each other on a substrate; A charge generating layer formed between the first and second electrodes; A first light emitting stack formed between the charge generating layer and the first electrode; A hole injection layer of a light emitting stack having a second light emitting stack formed between the charge generating layer and the second electrode and implementing blue among the first and second light emitting stacks is based on the volume of the hole injection layer. It characterized in that the dopant of the hole transport material of less than 0.5% to 10% is formed by doping the host formed of HAT-CN.

Description

Organic light emitting display device {ORGANIC LIGHT EMITTING DISPLAY}

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

With the recent advent of the information age, the display field for visually expressing electrical information signals has rapidly developed, and in response to this, various flat panel displays with excellent performance of thinning, lightening, and low power consumption have been developed. Device) is being developed.

Specific examples of such a flat panel display device include a liquid crystal display device (LCD), a plasma display panel device (PDP), a field emission display device (FED), and an organic light emitting display device (Organic Light Emitting Device: OLED) and the like.

Particularly, the organic light emitting display device is a self-luminous device, and has an advantage in that the response speed is faster and the light emission efficiency, luminance, and viewing angle are greater than other flat panel display devices.

Conventional organic light emitting display devices include a blue light emitting layer made of a blue fluorescent material to implement white. However, a blue fluorescent device having a blue light emitting layer made of a blue fluorescent material has a problem in that a light-emitting efficiency characteristic for each luminance decreases as the luminance increases, resulting in a roll-off phenomenon.

In order to solve the above problems, the present invention provides an organic light emitting display device capable of improving efficiency.

In order to achieve the above technical problem, an organic light emitting display device according to the present invention includes first and second electrodes facing each other on a substrate; A charge generating layer formed between the first and second electrodes; A first light emitting stack formed between the charge generating layer and the first electrode; A hole injection layer of a light emitting stack that implements blue among the first and second light emitting stacks is provided with a second light emitting stack formed between the charge generating layer and the second electrode, and a hole is transported to a host formed of HAT-CN. Characterized in that the dopant of the material is formed by doping less than 0.5% to 10%.

The dopant is characterized in that it is formed of the same material as any one of the first and second light emitting stack hole transport layer.

The first light emitting stack has a blue fluorescent light emitting layer, and the second light emitting stack is characterized by having a yellow-green phosphorescent light emitting layer.

And at least one third light emitting stack formed between the second light emitting stack and the second electrode.

The dopant is characterized in that it is formed of the same material as at least one hole transport layer of the first to third light emitting stacks.

The first and third light emitting stacks have a blue fluorescent light emitting layer, and the second light emitting stack has a yellow-green phosphorescent light emitting layer.

In order to achieve the above technical problem, an organic light emitting display device according to the present invention includes first and second electrodes facing each other on a substrate; A blue light emitting layer formed between the first and second electrodes; A hole injection layer and a hole transport layer formed between the blue light emitting layer and the first electrode; An electron transport layer is formed between the blue light emitting layer and the second electrode, and the hole injection layer is formed by doping less than 0.5% to 10% of a dopant of a hole transport material in a host formed of HAT-CN. do.

The dopant is characterized in that it is formed of the same material as the hole transport layer.

The dopant has a hole mobility faster than the electron mobility, it is characterized in that it is formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² .

The doping ratio of the dopant is characterized in that 1 to 5% based on the volume of the hole injection layer.

In the organic light emitting diode display according to the present invention, a hole injection layer is formed by doping a hole transport material into a host formed of hexaazatriphenylene (HAT-CN). Accordingly, since hole mobility of the hole injection layer is improved, hole injection characteristics at the interface between the hole injection layer and the hole transport layer are improved. As a result, a stable charge balance in the light emitting layer increases the specific gravity of excitons in which electrons and holes are combined, thereby improving light emission efficiency and reducing the roll-off phenomenon. In particular, power consumption can be reduced when applied to a large-area display panel.

1 is a cross-sectional view illustrating an organic light emitting display device according to a first exemplary embodiment of the present invention.
2A to 2C are diagrams for describing all-optical characteristics of a comparative example and an organic light emitting diode display according to a first exemplary embodiment of the present invention.
3 is a cross-sectional view illustrating an organic light emitting display device according to a second exemplary embodiment of the present invention.
4A to 4C are diagrams for describing all-optical characteristics of a comparative example and an organic light emitting diode display according to a second exemplary embodiment of the present invention.
5 is a cross-sectional view illustrating an organic light emitting display device according to a third exemplary embodiment of the present invention having three light emitting stacks.
6A and 6B are diagrams for describing all-optical characteristics of a comparative example and an organic light emitting diode display according to a third exemplary embodiment of the present invention.
7 is a cross-sectional view showing an organic light emitting display device according to the present invention having a color filter.

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

1 is a cross-sectional view showing an organic light emitting display device according to the present invention.

The organic light emitting display device illustrated in FIG. 1 includes first and second electrodes 102 and 104 and an organic light emitting layer 110 formed between the first and second electrodes 102 and 104.

One of the first and second electrodes 102 and 104 is formed of a transmissive electrode or a semi-transmissive electrode, and the other of the first and second electrodes 102 and 104 is formed of a reflective electrode. When the first electrode 102 is a semi-transmissive electrode and the second electrode 104 is a reflective electrode, it is a back light emitting structure that emits light downward. When the second electrode 104 is a semi-transmissive electrode and the first electrode 102 is a reflective electrode, it is a front emission structure that emits light upward. In the present invention, it will be described as an example that the first electrode 102 is formed of a reflective electrode as an anode, and the second electrode 104 is formed of a semi-transmissive electrode as a cathode.

The first electrode 102 is formed of a multi-layer structure including a metal layer made of aluminum (Al) or an aluminum alloy (AlNd), and a transparent layer made of Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), etc. Becomes a reflective electrode.

The second electrode 104 is formed of a single layer or multiple layers, and each layer constituting the second electrode 104 is formed of a metal, an inorganic material, a metal mixed layer, or a mixture of metals and inorganic materials or a mixture thereof. At this time, when each layer is a mixed layer of metal and inorganic, the ratio is formed from 10: 1 to 1:10, and when each layer is a mixed layer of metal and metal, the ratio is from 10: 1 to 1:10. Is formed. The metal constituting the second electrode 104 is formed of Ag, Mg, Yb, Li, or Ca, and the inorganic material is formed of Li ₂ O, CaO, LiF, or MgF ₂ , and assists electron migration to electrons into the light emitting layer 110 Make sure to supply a lot.

Between the first and second electrodes 102 and 104, a hole injection layer 112, a hole transport layer 114 (HTL), a light emitting layer 116 (EML (B)), and an electron transport layer 118 (ETL) are sequentially formed.

The hole injection layer 112 serves to facilitate hole injection from the first electrode 102. The hole transport layer 114 supplies holes from the hole injection layer 112 to the light emitting layer 116. The electron transport layer 118 supplies electrons from the second electrode 104 to the light emitting layer 116.

In the light emitting layer 116, holes are supplied through the hole transport layer 114 and electrons supplied through the electron transport layer 118 are recombined to generate light. In particular, the light emitting layer 116 is formed of a blue fluorescent material to realize blue.

The hole injection layer 112 of the organic light emitting diode display according to the first embodiment of the present invention is a host dopant 112b having a ratio of less than 0.5 to 10% based on the volume of the hole injection layer 112 ( Doped to 112a) is formed to a thickness of less than about 7nm. Here, the dopant 112b is preferably doped to the host 112a by 1 to 5% based on the volume of the hole injection layer 112. The host 112a is formed of hexaazatriphenylene (HAT-CN), and the dopant 112b is formed of a hole transport material having better hole mobility than electron mobility. At this time, the hole transport material is formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . For example, hole transport materials include NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'-bis- (3-methylphenyl) -N, N'-bis- (phenyl) ) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-Tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine) are used, and the hole transport layer 114 As a result, hole mobility of the hole injection layer 112 is improved, and thus hole injection characteristics at the interface between the hole injection layer 112 and the hole transport layer 114 are improved. The stable charge balance in (116) increases the specific gravity of excitons formed by the combination of electrons and holes, thereby improving luminous efficiency.

2A to 2C are diagrams for explaining all-optical characteristics according to the comparative example and the first embodiment.

Specifically, as illustrated in FIG. 2A, Example 1 having a hole injection layer 112 doped with 1 to 3% of dopant 112b is higher than the comparative example having a hole injection layer without dopants. Increasingly, as shown in Table 1, it can be seen that the efficiency of Example 1 at 10 mA / cm ² was increased by 7% or more than that of the Comparative Example.

10mA / cm ² Efficiency (Cd / A) QE (%) Color Coordinate (CIEx) Color Coordinate (CIEy) Roll off Comparative example 8.0 9.6 0.136 0.092 0.93 Example 1 8.6 10.3 0.137 0.092 1.05

In addition, a blue light emitting device having a hole injection layer 112 doped with 1 to 3% of dopant 112b as shown in FIG. 2B is a comparative example (a hole injection layer without a dopant, a dopant of 10%) The luminous efficiency is increased in the total luminance region than the doped hole injection layer and the blue light emitting device each having a dopant hole injection layer of 20% doped). Further, in Example 1 the roll-off factor of (Roll off Factor; ratio of efficiency at a current density of 50mA / cm ² Efficiency compared at a current density of 10mA / cm ²⁾ is 0.93 rolls as shown in Table 1 Off It is 1.05, which is higher than the comparative example showing the index characteristics. Therefore, it can be seen that the blue organic light emitting device according to the first embodiment of the present invention has improved the roll-off phenomenon in which efficiency is reduced in a high luminance region.

In particular, a blue light emitting device having a hole injection layer 112 doped with 1 to 3% of dopant 112b has a hole injection layer doped with 10% dopant and a hole injection layer doped with 20% dopant, respectively. It can be seen that the roll-off phenomenon in which the efficiency is reduced in the high luminance region is improved than the blue light emitting device. Accordingly, it can be seen that the blue light emitting device according to the first embodiment of the present invention preferably forms the content of the dopant in the hole injection layer to less than 0.5 to 10%.

In addition, as shown in Figure 2c, even if the material of the dopant (NPD, TPD, s-TAD, MTDATA) is different, an embodiment having a hole injection layer 112 doped with 1 to 3% of the dopant 112b It can be seen that the luminous efficiency of the blue light emitting device is increased in the total luminance region than the comparative example. Meanwhile, NPD, TPD, s-TAD, and MTDATA are described as examples of dopant materials, but the same effect can be obtained when other hole transport materials are used as dopants.

3 is a cross-sectional view illustrating an organic light emitting display device according to a second exemplary embodiment of the present invention.

The organic light emitting display device illustrated in FIG. 3 has the same components except for the two-stack structure as compared to the organic light emitting display device illustrated in FIG. 1. Accordingly, detailed description of the same components will be omitted.

The organic light emitting diode display illustrated in FIG. 3 includes first and second light emitting stacks 110 and 120 formed between the first and second electrodes 102 and 104 facing each other, and the first and second electrodes 102 and 104. And a charge generating layer 130 positioned between the second light emitting stacks 110 and 120. In the present invention, the case where two light emitting stacks are used has been described as an example, but may be formed of more light emitting stacks.

The first emission stack 110 is formed between the first electrode 102 and the charge generating layer 130. The first emission stack 110 includes a hole injection layer 112 sequentially formed on the first electrode 102, a first hole transport layer 114 (HTL), a first emission layer 116 (EML (B)), and a first emission layer 110. 1 Electron transport layer (118: ETL) is provided.

The second emission stack 120 is formed between the second electrode 104 and the charge generating layer 130. The second emission stack 120 includes a second hole transport layer 124 (HTL), a second emission layer 126 (EML (YG)), and a second electron transport layer 128 (ETL) sequentially formed on the charge generation layer 130. ).

The first light emitting layer 116 emits blue light as a light emitting layer containing a blue fluorescent dopant and a host, and the second light emitting layer 126 emits orange light as a light emitting layer containing a yellow-green phosphorescent dopant and a host. Accordingly, the blue light of the first light-emitting layer 116 and the orange light of the second light-emitting layer 126 may be mixed to realize white light. In addition, white light may be implemented using other fluorescent dopants and phosphorescent dopants.

The charge generation layer 130 is formed between the first and second light emitting stacks 110 and 120 to adjust charge balance between the light emitting stacks 110 and 120. The charge generation layer 130 includes an N-type charge generation layer 132 and a P-type charge generation layer 134 that are sequentially stacked.

The N-type charge generation layer 132 serves to inject electrons into the first emission stack 110, and the P-type charge generation layer 134 serves to inject holes into the second emission stack 120.

The electrons moved to the first light emitting stack 110 through the N-type charge generating layer 132 and the holes moved through the hole injection layer 112 and the hole transport layer 114 are the first of the first light emitting stack 110. The light emitting layer 116 combines to form excitons and emit energy while emitting light in the visible region.

 Holes moved to the second light emitting stack 120 through the P-type charge generation layer 134 and electrons moved through the second electrode 104 and the second electron transport layer 128 are the second light emitting stack 120. The second light emitting layer 126 combines to form excitons and emit energy while emitting light in the visible region.

In the organic light emitting diode display according to the second embodiment of the present invention, the hole injection layer 112 of the first light emitting stack 110 emitting blue light is 0.5 to 0.5 based on the volume ratio of the hole injection layer 112. A dopant 112b having a ratio of less than 10% is doped into the host 112a to form a thickness of about 7 nm or less. Here, it is preferable that the dopant 112b is doped at 1 to 5% based on the volume ratio of the hole injection layer 112 to the host 112a. The host 112a is formed of hexaazatriphenylene (HAT-CN), and the dopant 112b is formed of a hole transport material having better hole mobility than electron mobility. At this time, the hole transport material is formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . For example, hole transport materials include NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'-bis- (3-methylphenyl) -N, N'-bis- (phenyl) ) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-Tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine) are used, and the first and second luminescence Materials of the hole transport layers 114 and 124 of the stacks 110 and 120 may be used. Accordingly, since the hole mobility of the hole injection layer 112 of the first light emitting stack 110 is improved, the material of the first light emitting stack 110 is improved. The hole injection characteristics at the interface between the hole injection layer 112 and the hole transport layer 114 of the first light emitting stack 110 are improved. As a result, electrons and holes are balanced due to charge balance in the first light emitting layer 116. The formation specific gravity of the combined exciton is increased, and the luminous efficiency is improved.

4A to 4C are diagrams for describing all-optical characteristics according to the comparative example and the second embodiment.

Specifically, as illustrated in FIG. 4A, the organic light emitting diode display of Example 2 having the hole injection layer 112 of the first stack doped with 1 to 3% of the dopant 112b is the first in which the dopant is not doped. The peak intensity (YG peak) of the first emission layer 116, which realizes blue, and the peak intensity (YG peak) of the second emission layer 126, which implements orange, are increased compared to the comparative example having the hole injection layer of the emission stack. , As shown in Table 2, it can be seen that the efficiency of Example 2 at 10 mA / cm ² was increased by 6% or more than the comparative example.

10mA / cm ² Efficiency (Cd / A) QE (%) Color Coordinate (CIEx) Color Coordinate (CIEy) Roll off Comparative example 81.1 32.0 0.317 0.339 0.81 Example 2 86.5 35.1 0.324 0.330 0.84

In addition, as illustrated in FIG. 4B, the organic light emitting diode of Example 2 having the hole injection layer 112 of the first light emitting stack 110 doped with 1 to 3% of the dopant 112b emits light in a full luminance region. Efficiency comparison example (hole injection layer of the first light emitting stack without dopant doped, hole injection layer of the first light emitting stack doped with 10% dopant, and hole injection of the first light emitting stack doped with 20% dopant) Organic light emitting device having each layer). Further, in Example 2 the roll-off factor of (Roll off Factor; ratio of efficiency at a current density of 50mA / cm ² Efficiency compared at a current density of 10mA / cm ²⁾ is 0.81 rolls as shown in Table 2 Off It is 0.84, which is higher than the comparative example showing the index characteristics. Therefore, it can be seen that the roll-off phenomenon in which the efficiency is reduced in the high luminance region of the multi-emission stack organic light emitting display device according to the second embodiment of the present invention is improved.

In particular, the organic light emitting device of Example 2 having the hole injection layer 112 of the first light emitting stack 110 doped with 1 to 3% of the dopant 112b has a hole injection layer doped with 10% dopant and 20 It can be seen that the roll-off phenomenon in which the efficiency is reduced in the high luminance region is improved compared to the organic light emitting device having each of the dopant-doped hole injection layers. Therefore, it can be seen that the organic light emitting device according to the second embodiment of the present invention preferably forms the content of the dopant in the hole injection layer 112 of the first light emitting stack 110 to less than 0.5 to 10%.

In addition, as illustrated in FIG. 4C, the organic light emitting device of Example 2 having the hole injection layer 112 doped with 1 to 3% of the dopant 112b, even when the material of the dopant (NPD, TPD) is different, It can be seen that the luminous efficiency is increased in the total luminance region than the comparative example. Meanwhile, NPD and TPD are described as examples of the dopant material, but the same effect can be obtained when other hole transport materials are used as the dopant.

Meanwhile, in the second embodiment of the present invention, the case where two light emitting stacks are used is described as an example, but may be formed of more light emitting stacks. For example, it may be formed of three light emitting stacks (110,120,140) as shown in FIG.

The organic light emitting diode display illustrated in FIG. 5 includes first and third light emitting stacks 110, 120 and 140 formed between the first and second electrodes 102 and 104 facing each other, and the first and second electrodes 102 and 104. And a charge generating layer 130 positioned between the second light emitting stacks 110 and 120 and between the second and third light emitting stacks 120 and 140.

The first emission stack 110 is formed between the first electrode 102 and the charge generating layer 130. The first emission stack 110 includes a hole injection layer 112 sequentially formed on the first electrode 102, a first hole transport layer 114 (HTL), a first emission layer 116 (EML (B)), and a first emission layer 110. 1 electron transport layer (118; HTL) is provided.

The second light emitting stack 120 is formed between the first and third light emitting stacks 110 and 140. The second emission stack 120 includes a second hole transport layer 124 (HTL), a second emission layer 126 (EML (YG)), and a second electron transport layer 128 (ETL) sequentially formed on the charge generation layer 130. ).

The third emission stack 120 is formed between the second electrode 104 and the charge generation layer 130. The third emission stack 120 includes a third hole transport layer 144 (HTL), a third emission layer 146 (EML (B)), and a third electron transport layer 148 (ETL) sequentially formed on the charge generation layer 130. ).

The first and third light emitting layers 116 and 146 emit blue light as a light emitting layer containing a blue fluorescent dopant and a host, and the second light emitting layer 126 emits orange light as a light emitting layer containing a yellow-green phosphorescent dopant and a host. do. Accordingly, blue light of the first and third light-emitting layers 116 and 146 and orange light of the second light-emitting layer 126 may be mixed to realize white light. Particularly, in the third embodiment of the present invention, since the third light emitting layer 146 that implements blue color is further provided in comparison with the organic light emitting diode display illustrated in FIG. 3, efficiency of blue light is improved. In addition, white light may be implemented using other fluorescent dopants and phosphorescent dopants.

The charge generating layer 130 is formed between the first and second light emitting stacks 110 and 120 and between the second and third light emitting stacks 120 and 140 to adjust charge balance between the light emitting stacks 110 and 120 and 140. The charge generation layer 130 includes an N-type charge generation layer 132 and a P-type charge generation layer 134 that are sequentially stacked.

The N-type charge generation layer 132 serves to inject electrons into the first and second emission stacks 110 and 120, and the P-type charge generation layer 134 serves as the second and third emission stacks 120 and 140. It serves to inject holes.

The electrons moved to the first light emitting stack 110 through the N-type charge generating layer 132 and the holes moved through the hole injection layer 112 and the first hole transport layer 114 are the same as those of the first light emitting stack 110. Combined in the first light emitting layer 116 to form excitons and emit energy while emitting light in the visible region.

The electrons moved to the second light emitting stack 120 through the N-type charge generating layer 132 and the holes moved to the second light emitting stack 120 through the P-type charge generating layer 134 are the second light emitting stack 120 ) Combines in the second light emitting layer 126 to form excitons and emit energy while emitting light in the visible region.

 Holes moved to the third emission stack 140 through the P-type charge generation layer 134 and electrons moved through the second electrode 104 and the third electron transport layer 148 are transferred to the third emission stack 140. The third light emitting layer 146 combines to form excitons and emit energy while emitting light in the visible region.

In the organic light emitting diode display according to the third embodiment of the present invention, the hole injection layer 112 of the first light emitting stack 110 emitting blue light has a dopant 112b having a ratio of 0.5 to less than 10%. Is doped into the host 112a and is formed to a thickness of about 7 nm or less. Here, the dopant 112b is preferably doped to the host 112a by 1 to 5% based on the volume of the hole injection layer 112. The host 112a is formed of hexaazatriphenylene (HAT-CN), and the dopant 112b is formed of a hole transport material having better hole mobility than electron mobility. At this time, the hole transport material is formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . For example, hole transport materials include NPD (N, N-dinaphthyl-N, N'-diphenyl benzidine), TPD (N, N'-bis- (3-methylphenyl) -N, N'-bis- (phenyl) ) -benzidine), s-TAD and MTDATA (4,4 ', 4 "-Tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine) are used, and the first to third light emission A material of at least one of the hole transport layers 114, 124, and 144 of the stacks 110, 120, and 140 may be used. Accordingly, hole movement of the hole injection layer 112 of the first light emitting stack 110 including the hole transport material may be used. Since the degree is improved, the hole injection characteristics at the interface between the hole injection layer 112 of the first light emitting stack 110 and the hole transport layer 114 of the first light emitting stack 110 are improved. As a result, the first light emitting layer ( The charge density within 116) increases the specific gravity of formation of excitons in which electrons and holes are combined, thereby improving luminous efficiency.

6A and 6B are diagrams for explaining all-optical characteristics according to the comparative example and the third embodiment.

Specifically, as illustrated in FIG. 6A, the organic light emitting diode display of Embodiment 3 having the hole injection layer 112 of the first light emitting stack 110 doped with the dopant 112b has a first light emission in which the dopant is not doped. The peak intensity (YG peak) of the first emission layer 116, which realizes blue, and the peak intensity (YG peak) of the second emission layer 126, which implements orange, are increased compared to the comparative example having the hole injection layer of the stack, As shown in Table 3, it can be seen that the efficiency of Example ² at 10 mA / cm ² was increased by 2.9% or more than the comparative example.

10mA / cm ² Efficiency (Cd / A) Roll off Comparative example 84.9 0.85 Example 3 87.8 0.87

In addition, as illustrated in FIG. 6B, the organic light emitting diode of Example 2 having the hole injection layer 112 of the first light emitting stack 110 doped with 1 to 3% of the dopant 112b emits light in the full luminance region. The efficiency is higher than that of the comparative example (an organic light emitting device having a hole injection layer of the first light emitting stack in which the dopant is not doped). Further, in Example 3 the roll-off factor of (Roll off Factor; ratio of efficiency at a current density of 50mA / cm ² Efficiency compared at a current density of 10mA / cm ²⁾ is 0.85 rolls as shown in Table 3 Off It is 0.87, which is higher than the comparative example showing the index characteristics. Accordingly, it can be seen that the roll-off phenomenon in which the efficiency is reduced in the high luminance region of the multi-emission stack organic light emitting display device according to the third embodiment of the present invention is improved.

The organic light emitting display device according to the present invention is also applicable to a structure having red, green, and blue color filters 150R, 150G, and 150B as shown in FIG. 7. The white light generated through the first and second light emitting stacks 110 and 120 shown in FIG. 3 or the white light generated through the first to third light emitting stacks 110 and 120 and 140 shown in FIG. 5 is formed with a red color filter 150R. Red light is emitted while passing through the sub-pixel area, green light is emitted while passing through the sub-pixel area where the green color filter 150G is formed, blue light is emitted while passing through the sub-pixel area where the blue color filter 150B is formed, and color White light is emitted while passing through the sub-pixel region where the filter is not formed.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications and changes are possible within the scope of the present invention without departing from the technical spirit of the present invention. It will be clear to those who have the knowledge of

102: first electrode 104: second electrode
110,120,140: light emitting stack 130: charge generating layer

Claims (14)

First and second electrodes facing each other on the substrate;
A charge generation layer disposed between the first and second electrodes;
A first light emitting stack disposed between the charge generating layer and the first electrode;
And a second light emitting stack disposed between the charge generating layer and the second electrode,
The hole injection layer of the light emitting stack implementing blue color among the first and second light emitting stacks is doped with a host formed of HAT-CN with a dopant of 1% to 3% of a hole transport material based on the volume of the hole injection layer. An organic light emitting display device formed. According to claim 1,
The dopant is an organic light emitting display device formed of the same material as the hole transport layer of any one of the first and second light emitting stacks. According to claim 1,
The dopant has an electron mobility faster than the electron mobility, the organic light emitting display device formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . delete According to claim 1,
The first light emitting stack has a blue fluorescent light emitting layer,
The second light emitting stack is an organic light emitting display device having a yellow-green phosphorescence emitting layer. According to claim 1,
And at least one third emission stack disposed between the second emission stack and the second electrode. The method of claim 6,
The dopant is an organic light emitting display device formed of the same material as at least one hole transport layer of the first to third light emitting stacks. The method of claim 6,
The dopant has an electron mobility faster than the electron mobility, the organic light emitting display device formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . delete The method of claim 6,
The first and third emission stacks include a blue fluorescent emission layer,
The second light emitting stack is an organic light emitting display device having a yellow-green phosphorescence emitting layer. First and second electrodes facing each other on the substrate;
A blue light emitting layer disposed between the first and second electrodes;
A hole injection layer and a hole transport layer disposed between the blue light emitting layer and the first electrode;
And an electron transport layer disposed between the blue light emitting layer and the second electrode,
The hole injection layer is an organic light emitting display device formed by doping a host formed of HAT-CN with a dopant of 1% to 3% hole transport material based on the volume of the hole injection layer. The method of claim 11,
The dopant is an organic light emitting display device formed of the same material as the hole transport layer. The method of claim 11,
The dopant has an electron mobility faster than the electron mobility, the organic light emitting display device formed of a material having a hole mobility of 5.0 × 10 ^-5 Vs / cm ² ~ 1.0 × 10 ^-2 Vs / cm ² . delete

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