Organic light emitting display device and method of manufacturing an organic light emitting display device
An organic light emitting display device may include a substrate, an anode, an auxiliary electrode, a light emitting structure, a lower cathode, and an upper cathode. The substrate may include a pixel region, a transparent region, and a boundary region between the pixel region and the transparent region. The anode may be on the pixel region. The auxiliary electrode may be on the transparent or boundary regions. The light emitting structure may be on the anode and the auxiliary electrode and extended from the pixel region to the transparent region. The lower cathode may be on the light emitting structure and made thin to increase transmittance. The upper cathode may be on the lower cathode. The thin lower cathode may be electrically connected to the auxiliary electrode via a contact hole which penetrates the light emitting structure so as to reduce a voltage drop.
1. An organic light emitting display (OLED) device, comprising:
a substrate comprising a pixel region, a transparent region, and a boundary region between the pixel region and the transparent region;
an anode disposed on the pixel region;
an auxiliary electrode disposed on the transparent region or the boundary region;
a light emitting structure disposed on the anode and the auxiliary electrode, the light emitting structure being extended from the pixel region to the transparent region;
a lower cathode disposed on the light emitting structure; and
an upper cathode disposed on the lower cathode,
wherein the lower cathode is electrically connected to the auxiliary electrode via a contact hole which penetrates the light emitting structure.
2. The OLED device of claim 1 , wherein a thickness of the lower cathode is less than the thickness of the upper cathode.
3. The OLED device of claim 1 , wherein a light transmittance of the upper cathode is greater than a light transmittance of the lower cathode.
4. The OLED device of claim 3 , wherein the upper cathode comprises at least one material selected from the group consisting of titanium oxide (TiO x ), indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO x ), magnesium oxide (MgO x ), poly(3,4-ethylenedioxyehiophene) polystyrene sulfonate (PEDOT:PSS), graphene, and carbon nanotube (CNT).
5. The OLED device of claim 1 , wherein the lower cathode comprises at least one material selected from the group consisting of gold (Au), aluminum (Al), silver (Ag), magnesium-silver alloy (MgAg), and silver-magnesium alloy (AgMg).
6. The OLED device of claim 1 , wherein the anode and the auxiliary electrode are disposed on substantially the same plane.
7. The OLED device of claim 6 , wherein the anode and the auxiliary electrode comprise substantially the same material.
8. The OLED device of claim 7 , wherein the anode and the auxiliary electrode comprise a transparent material.
9. The OLED device of claim 1 , wherein the anode and the auxiliary electrode are disposed on different planes.
10. The OLED device of claim 9 , wherein the anode and the auxiliary electrode comprise different materials.
11. The OLED device of claim 10 , wherein a light transmittance of the auxiliary electrode is greater than the light transmittance of the anode.
12. The OLED device of claim 11 , wherein the auxiliary electrode is disposed on the transparent region.
13. The OLED device of claim 1 , further comprising a semiconductor element electrically connected to the anode.
14. The OLED device of claim 1 , wherein the light emitting structure comprises:
a hole injection layer disposed on the anode;
a hole transport layer disposed on the hole injection layer;
an organic light emitting layer disposed on the hole transport layer;
an electron transport layer disposed on the organic light emitting layer; and
an electron injection layer disposed on the electron transport layer.
15. A method of manufacturing an organic light emitting display (OLED) device, comprising:
providing a substrate comprising a pixel region, a transparent region, and a boundary region between the pixel region and the transparent region;
forming an anode on the pixel region;
forming an auxiliary electrode on the transparent region or the boundary region;
forming a light emitting structure on the anode and the auxiliary electrode, the light emitting structure being extended from the pixel region to the transparent region;
forming a contact hole which penetrates the light emitting structure to expose the auxiliary electrode;
forming a lower cathode on the light emitting structure, the lower cathode being electrically connected to the auxiliary electrode via the contact hole; and
forming an upper cathode on the lower cathode.
16. The method of claim 15 , wherein the contact hole is formed by a laser drilling process.
17. The method of claim 16 , wherein the laser drilling process is performed under an inert gas atmosphere.
18. The method of claim 16 , wherein the laser drilling process is performed under a vacuum atmosphere.
19. The method of claim 15 , further comprising forming a semiconductor element electrically connected to the anode.
20. The method of claim 15 , wherein forming the light emitting structure comprises:
forming a hole injection layer on the anode;
forming a hole transport layer on the hole injection layer;
forming an organic light emitting layer on the hole transport layer;
forming an electron transport layer on the organic light emitting layer; and
forming an electron injection layer on the electron transport layer.