Quantum dot LED and OLED integration for high efficiency displays

• US 10,461,131 B2
• Filed: 12/13/2018
• Issued: 10/29/2019
• Est. Priority Date: 02/02/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Steckel, Jonathan S., Mathai, Mathew K., Drzaic, Paul S., Yamamoto, Hitoshi
• Primary Examiner(s): Hall, Victoria K.
• Application Number:
  US16/219,898
• Publication Number:
  US 20190131356A1
• Time in Patent Office: 320 Days
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/115 comprising active inorganic nanostructures, e.g. luminescent quantum dots
• CPC Class Codes: H10K 50/131 with spacer layers between the electroluminescent layers
• CPC Class Codes: H10K 50/16 Electron transporting layers
• CPC Class Codes: H10K 50/19 Tandem OLEDs
• CPC Class Codes: H10K 59/32 Stacked devices having two or more layers, each emitting at different wavelengths
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels
• CPC Class Codes: H10K 71/12 using liquid deposition, e.g. spin coating
• CPC Class Codes: H10K 71/18 using non-liquid printing techniques, e.g. thermal transfer printing from a donor sheet

Abstract

Displays including hybrid pixels including an OLED subpixel and QD-LED subpixel are described. In an embodiment, OLED and QD-LED stacks are integrated into the same pixel with multiple common layers shared by the OLED and QD-LED stacks.

Claims

1. A display comprising:

a tandem hybrid pixel including an organic light emitting diode (OLED) subpixel and a quantum dot light emitting diode (QD-LED) subpixel;

a common hole transport layer in the OLED subpixel and the QD-LED subpixel;

a common quantum dot layer over the common hole transport layer in the QD-LED subpixel and in the OLED subpixel;

a semi-common charge generation layer over the common quantum dot layer in the OLED subpixel;

a first cathode over the common quantum dot layer in the QD-LED subpixel;

a semi-common hole transport layer over the semi-common charge generation layer in the OLED subpixel;

an organic emission layer over the semi-common hole transport layer in the OLED subpixel;

a semi-common electron transport layer over the organic emission layer in the OLED subpixel; and

a semi-common second cathode over the semi-common electron transport layer in the OLED subpixel.

2. The display of claim 1, further comprising:

a common nanoparticle electron transport layer comprising metal-oxide nanoparticles over the common quantum dot layer in the QD-LED subpixel and in the OLED subpixel;

wherein the semi-common charge generation layer is over the common nanoparticle electron transport layer in the OLED subpixel, and the first cathode is over the common nanoparticle electron transport layer in the QD-LED subpixel.

3. The display of claim 1, wherein the organic emission layer is over the common quantum dot layer in the OLED subpixel.

4. The display of claim 1, further comprising a first anode under the common hole transport layer in the QD-LED subpixel, and a second anode under the common hole transport layer in the OLED subpixel.

5. The display of claim 1, wherein the organic emission layer comprises a phosphorescent material.

6. A display comprising:

a tandem hybrid pixel including an organic light emitting diode (OLED) subpixel and a quantum dot light emitting diode (QD-LED) subpixel;

a common hole transport layer in the OLED subpixel and the QD-LED subpixel;

a common quantum dot layer over the common hole transport layer in the QD-LED subpixel and in the OLED subpixel;

a common charge generation layer over the common quantum dot layer in the OLED subpixel and in the QD-LED subpixel;

a second common hole transport layer over the common charge generation layer in the OLED subpixel and in the QD-LED subpixel;

an organic emission layer over the second common hole transport layer in the OLED subpixel;

a common electron transport layer over the second common hole transport layer in the OLED subpixel and in the QD-LED subpixel, the common electron transport layer additionally over the organic emission layer in the OLED subpixel; and

a common cathode over the common electron transport layer in the OLED subpixel and in the QD-LED subpixel.

7. The display of claim 6, further comprising:

a common nanoparticle electron transport layer comprising metal-oxide nanoparticles over the common quantum dot layer in the QD-LED subpixel and in the OLED subpixel;

wherein the common charge generation layer is over the common nanoparticle electron transport layer in the OLED subpixel and in the QD-LED subpixel.

8. The display of claim 6, wherein the organic emission layer is over the common quantum dot layer in the OLED subpixel.

9. The display of claim 6, further comprising a first anode under the common hole transport layer in the QD-LED subpixel, and a second anode under the common hole transport layer in the OLED subpixel.

10. The display of claim 6, wherein the organic emission layer comprises a phosphorescent material.

11. A display with tandem QD-LED and OLED tandem stack comprising:

a common anode;

a common hole transport layer over the common anode;

a common quantum dot layer over the common hole transport layer;

a common charge generation layer over the common quantum dot layer;

a second common hole transport layer over the common charge generation layer;

a common organic emission layer over the second common hole transport layer;

a common electron transport layer over the common organic emission layer; and

a common cathode over the common electron transport layer.

12. The display of claim 11, further comprising a second common organic emission layer between the common organic emission layer and the common electron transport layer.

13. The display of claim 12, further comprising:

a second common electron transport layer over the common organic emission layer;

a second charge generation layer over the second common electron transport layer; and

a third common hole transport layer over the second charge generation layer;

wherein the second common organic emission layer is over the third common hole transport layer.

14. The display of claim 11, further comprising a second common electron transport layer between the common quantum dot layer and the common charge generation layer.

15. The display of claim 14, wherein the second common electron transport layer comprises metal-oxide nanoparticles.