Methods of manufacturing OLED pixel and display device

1. A method of manufacturing an Organic Light Emitting Diode (OLED) pixel, wherein the OLED pixel at least comprises a first sub-pixel, a second sub-pixel and a third sub-pixel, wherein the method of manufacturing the OLED pixel comprises:

forming an anode on a substrate;

forming a pixel definition layer on the substrate, wherein the pixel definition layer comprises:

a first sub-pixel area corresponding to the first sub-pixel,

a second sub-pixel area corresponding to the second sub-pixel,

a third sub-pixel area corresponding to the third sub-pixel, and

a pixel spacing area,

wherein the first sub-pixel, the second sub-pixel and the third sub-pixel are separated from each other by the pixel spacing area;

coating a first long-chain fatty acid ester layer on the pixel spacing area, the second sub-pixel area, and the third sub-pixel area;

coating a first light emitting layer on the first sub-pixel area and on the first long-chain fatty acid ester layer;

ashing the substrate, and removing the first long-chain fatty acid ester layer to form a first light emitting pattern;

coating a second long-chain fatty acid ester layer on the pixel spacing area, the first light emitting pattern, and the third sub-pixel area;

coating a second light emitting layer on the second sub-pixel area and the second long-chain fatty acid ester layer;

ashing the substrate, and removing the second long-chain fatty acid ester layer to form a second light emitting pattern;

coating a third long-chain fatty acid ester layer on the pixel spacing area, the first light emitting pattern, and the second light emitting pattern;

coating a third light emitting layer on the third sub-pixel area and the third long-chain fatty acid ester layer;

ashing the substrate, and removing the third long-chain fatty acid ester layer to form a third light emitting pattern; and

forming a cathode.

2. The method of claim 1 , wherein the first long-chain fatty acid ester or the second long-chain fatty acid ester or the third long-chain fatty acid ester is CH3(CH2)22COOH.

3. The method of claim 1 , wherein at least one of the first long-chain fatty acid ester layer, the second long-chain fatty acid ester layer, and the third long-chain fatty acid ester layer is coated with a silk-screen printing process.

4. The method of claim 1 , wherein at least one of the first light emitting layer, the second light emitting layer, and the third light emitting layer is coated with a spin coating process.

5. The method of claim 1 , wherein a thickness of at least one of the first long-chain fatty acid ester layer, the second long-chain fatty acid ester layer, and third long-chain fatty acid ester layer is 10 Å.

6. The method of claim 1 , wherein the first light emitting layer is a red light emitting layer, the second light emitting layer is a green light emitting layer, and the third light emitting layer is a blue light emitting layer.

7. The method of claim 6 , wherein a thickness of at least one of the first light emitting layer, the second light emitting layer, and the third light emitting layer is 100 Å to 1000 Å.

8. The method of claim 7 , wherein a thickness of the red light emitting layer is 410 Å, and a thickness of at least one of the blue light emitting layer and the green light emitting layer is 390 Å to 400 Å.

9. The method of claim 1 , wherein the method further comprises at least one of:

a) before coating the second long-chain fatty acid ester layer, baking the substrate, and

b) before coating the third long-chain fatty acid ester layer, baking the substrate.

10. The method of claim 1 , wherein the OLED pixel further comprises a fourth sub-pixel, the pixel definition layer further comprises a fourth sub-pixel area corresponding to the fourth sub-pixel, and the fourth sub-pixel is separated from the first sub-pixel, the second sub-pixel and the third sub-pixel by the pixel spacing area, and

wherein, after forming the third light emitting pattern and before forming the cathode, the method of manufacturing the OLED pixel further comprises:

coating a fourth long-chain fatty acid ester layer on the pixel spacing area, the first light emitting pattern, the second light emitting pattern, and the third light emitting pattern;

coating a fourth light emitting layer on the fourth sub-pixel area and the fourth long-chain fatty acid ester layer; and

ashing the substrate, and removing the fourth long-chain fatty acid ester layer to form a fourth light emitting pattern.

11. The method of claim 10 , wherein the fourth long-chain fatty acid ester is CH3(CH2)22COOH, or a thickness of the fourth long-chain fatty acid ester layer is 10 Å, or a thickness of the fourth light emitting layer is 100 Å to 1000 Å.

12. The method of claim 10 , wherein the fourth long-chain fatty acid ester layer is coated with a silk-screen printing process, and the fourth light emitting layer is coated using a spin coating process.

13. The method of claim 10 , wherein the fourth light emitting layer is any one of red, green, blue, yellow, and white light emitting layers.

14. A method of manufacturing an OLED display device, the method comprising:

forming multiple OLED pixels on a first substrate; and

adhering the first substrate to a second substrate through a frit to form the OLED display device,

wherein each OLED pixel comprises:

a first sub-pixel,

a second sub-pixel, and

a third sub-pixel, and

wherein forming the multiple OLED pixels on the first substrate comprises:

forming an anode and a pixel definition layer on the first substrate, wherein the pixel definition layer comprises:

multiple first sub-pixel areas corresponding to the first sub-pixels,

multiple second sub-pixel areas corresponding to the second sub-pixels,

multiple third sub-pixel areas corresponding to the third sub-pixels, and

a pixel spacing area,

wherein the first sub-pixels, the second sub-pixels and the third sub-pixels are separated from each other by the pixel spacing area;

coating a first long-chain fatty acid ester layer on the pixel spacing area, the second sub-pixel areas, and the third sub-pixel areas;

coating a first light emitting layer on the first sub-pixel areas and the first long-chain fatty acid ester layer;

ashing the first substrate, and removing the first long-chain fatty acid ester layer to form first light emitting patterns;

coating a second long-chain fatty acid ester layer on the pixel spacing area, the first light emitting patterns, and the third sub-pixel areas;

coating a second light emitting layer on the second sub-pixel areas and the second long-chain fatty acid ester layer;

ashing the first substrate, and removing the second long-chain fatty acid ester layer to form second light emitting patterns;

coating a third long-chain fatty acid ester layer on the pixel spacing area, the first light emitting patterns, and the second light emitting patterns;

coating a third light emitting layer on the third sub-pixel areas and the third long-chain fatty acid ester layer;

ashing the first substrate, and removing the third long-chain fatty acid ester layer to form third light emitting patterns; and

forming a cathode.