Color OLED display with a larger aperture ratio

• US 10,468,637 B2
• Filed: 01/10/2018
• Issued: 11/05/2019
• Est. Priority Date: 08/01/2014
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Orthogonal, Inc.
• Inventors: Defranco, John Andrew, O'Toole, Terrence Robert, Byrne, Frank Xavier, Freeman, Diane Carol
• Primary Examiner(s): Chambliss, Alonzo
• Application Number:
  US15/867,019
• Publication Number:
  US 20180159089A1
• Time in Patent Office: 664 Days
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/15 Hole transporting layers
• CPC Class Codes: H10K 50/16 Electron transporting layers
• CPC Class Codes: H10K 50/171 Electron injection layers
• CPC Class Codes: H10K 50/18 Carrier blocking layers
• CPC Class Codes: H10K 50/30 Organic light-emitting transistors
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 59/125 including organic TFTs [OTFT]
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 59/353 characterised by the geometrical arrangement of the RGB subpixels
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: H10K 71/221 by lift-off techniques
• CPC Class Codes: H10K 71/233 by photolithographic etching
• CPC Class Codes: H10K 85/00 Organic materials used in the body or electrodes of devices covered by this subclass
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method of making an OLED device includes providing a first undercut lift-off structure over the device substrate having a first array of bottom electrodes. Next, one or more first organic EL medium layers including at least a first light-emitting layer are deposited over the first undercut lift-off structure and over the first array of bottom electrodes. The first undercut lift-off structure and overlying first organic EL medium layer(s) are removed by treatment with a first lift-off agent comprising a fluorinated solvent to form a first intermediate structure. The process is repeated using a second undercut lift-off structure to deposit one or more second organic EL medium layers over a second array of bottom electrodes. After removal of the second undercut lift-off structure, a common top electrode is provided in electrical contact with the first and second organic EL medium layers.

Claims

1. A full color OLED display comprising:

a substrate having a display region, the display region including an array of first, second and third organic EL elements, each array having individually patterned light-emitting layers for emission of differently colored light,

wherein the display region has an aperture ratio of greater than about 60% and a resolution of greater than about 600 ppi.

2. The OLED display of claim 1, wherein the aperture ratio is greater than about 70%.

3. The OLED display of claim 1, wherein the display region has a resolution of greater than about 700 ppi.

4. The OLED display of claim 1, wherein the display region has a resolution of greater than about 800 ppi.

5. The OLED display of claim 1, wherein each of the first, second and third organic elements are less than about 25 microns in size in any dimension.

6. The OLED display of claim 1, wherein each of the first, second and third organic elements are less than about 15 microns in size in any dimension.

7. The OLED display of claim 1, wherein each of the first, second and third organic elements are less than about 5 microns in size in any dimension.

8. The OLED display of claim 1, wherein the first, second and third organic EL elements emit red, green, and blue light, respectively.

9. The OLED display of claim 1, wherein the combined emissive area of a first, second, and third organic EL element is less than about 1100 square microns.

10. The OLED display of claim 1, wherein the combined emissive area of a first, second, and third organic EL element is less than about 500 square microns.

11. A full color OLED display comprising:

a substrate having a display region, the display region including an array of first, second and third sub-pixels, each array having individually patterned light-emitting layers for emission of differently colored light,

wherein each of the first, second and third sub-pixels has a size of less than about 25 microns in any dimension and the display region has an aperture ratio of greater than about 60%.

12. The OLED display of claim 11, wherein each of the first, second and third sub-pixels has a size of less than about 20 microns in any dimension.

13. The OLED display of claim 11, wherein each of the first, second and third sub-pixels has a size of less than about 15 microns in any dimension.

14. The OLED display of claim 11, wherein each of the first, second and third sub-pixels are spaced apart from each other by less than about 5 microns.

15. The OLED display of claim 11, wherein the first, second and third sub-pixels comprise a unit cell having a display region area of less than about 1100 square microns.

16. A top-emitting full color OLED display comprising:

an active-matrix substrate having a display region, the display region including an array of first, second and third organic EL elements, each array having individually patterned light-emitting layers for emission of differently colored light; and

a transparent or translucent top electrode disposed above the EL elements,

wherein the display region has an aperture ratio of greater than about 60% and a resolution of greater than about 600 ppi.