Organic light-emitting diode display with pixel definition layers

Patent metadata

Field	Value
Publication number	US-12108632-B2
Application number	US-202318193999-A
Country	US
Kind code	B2
Filing date	Mar 31, 2023
Priority date	Mar 28, 2019
Publication date	Oct 1, 2024
Grant date	Oct 1, 2024

Abstract

An organic light-emitting diode (OLED) display may have an array of organic light-emitting diode pixels that each have OLED layers interposed between a cathode and an anode. Voltage may be applied to the anode of each pixel to control the magnitude of emitted light. The conductivity of the OLED layers may allow leakage current to pass between neighboring anodes in the display. To reduce leakage current and the accompanying cross-talk in a display, the pixel definition layer may disrupt continuity of the OLED layers. The pixel definition layer may have an undercut to disrupt continuity of some but not all of the OLED layers. The undercut may be defined by three discrete portions of the pixel definition layer. The undercut may result in a void that is interposed between different portions of the OLED layers to break a leakage path formed by the OLED layers.

First claim

What is claimed is:

1. A display comprising:
a substrate;
an array of pixels that includes first and second organic light-emitting diode pixels, wherein the first organic light-emitting diode pixel includes a first patterned electrode on the substrate and wherein the second organic light-emitting diode pixel includes a second patterned electrode on the substrate;
at least two layers on the substrate that are interposed between the first and second patterned electrodes, wherein the at least two layers comprise a first layer that is formed on the first patterned electrode and that has an edge surface at a non-orthogonal angle relative to an upper surface of the first patterned electrode, wherein the at least two layers comprise a second layer formed over the first layer, wherein the first layer is interposed between the second layer and the first patterned electrode, and wherein the edge surface is not directly overlapped by the second layer; and
a conductive layer formed over the at least one layer that has a first portion that forms part of the first organic light-emitting diode pixel and a second portion, wherein the second portion is electrically isolated from the first portion by a void that is at least partially defined by an undercut in the at least one layer.

2. The display defined in claim 1 , wherein the non-orthogonal angle is less than 90 degrees.

3. The display defined in claim 1 , wherein the non-orthogonal angle is between 45 degrees and 90 degrees.

4. The display defined in claim 1 , wherein the non-orthogonal angle is between 10 degrees and 45 degrees.

5. The display defined in claim 1 , wherein the at least two layers comprise a third layer that is formed over the second layer, wherein the second layer is interposed between the first layer and the third layer, and wherein the edge surface is not directly overlapped by the third layer.

6. The display defined in claim 5 , wherein the first and third layers comprise silicon dioxide and wherein the second layer comprises silicon nitride.

7. The display defined in claim 1 , wherein the first layer comprises silicon dioxide.

8. The display defined in claim 1 , wherein the first layer is in direct contact with the upper surface of the first patterned electrode.

9. The display defined in claim 8 , wherein the first layer is in direct contact with an edge of the first patterned electrode.

10. A display comprising:
a substrate;
an array of pixels that includes first and second organic light-emitting diode pixels, wherein the first organic light-emitting diode pixel includes a first patterned electrode on the substrate and wherein the second organic light-emitting diode pixel includes a second patterned electrode on the substrate;
a first layer that is formed on the first patterned electrode and that has an edge surface at a non-orthogonal angle relative to an upper surface of the first patterned electrode;
a second layer that is formed on an upper surface of the first layer; and
a third layer that is formed on the second layer, wherein the first, second, and third layers collectively define an undercut.

11. The display defined in claim 10 , further comprising:
a conductive layer formed over the third layer that has a first portion that forms part of the first organic light-emitting diode pixel and a second portion, wherein the second portion is electrically isolated from the first portion by a void that is at least partially defined by the undercut.

12. The display defined in claim 10 , wherein the first and third layers comprise silicon dioxide.

13. The display defined in claim 12 , wherein the second layer comprise silicon nitride.

14. The display defined in claim 10 , wherein the first and third layers comprise a first material and wherein the second layer comprises a second material that is different than the first material.

15. The display defined in claim 10 , wherein the non-orthogonal angle is less than 90 degrees.

16. The display defined in claim 10 , wherein an edge of the third layer extends past an edge of the second layer towards a center of the first patterned electrode.

17. The display defined in claim 10 , wherein the undercut has a height that is a distance between the upper surface of the first layer and a lower surface of the third layer.

18. The display defined in claim 10 , wherein the third layer is formed on an upper surface of the second layer.

19. A display comprising:
a substrate;
an array of pixels that includes first and second pixels, wherein the first pixel includes a first patterned electrode on the substrate and wherein the second pixel includes a second patterned electrode on the substrate;
three layers on the substrate that are interposed between the first and second patterned electrodes, wherein three layers comprise a first layer that is formed on the first patterned electrode and that has an edge surface at a non-orthogonal angle relative to an upper surface of the first patterned electrode, wherein the three layers comprise a second layer and a third layer, wherein the second layer is interposed between the first and third layers, and wherein an edge of the third layer extends past an edge of the second layer towards a center of the first patterned electrode; and
a conductive layer formed over the at least one layer that has a discontinuity caused by an undercut in the at least one layer.

20. The display defined in claim 19 , wherein the non-orthogonal angle is less than 90 degrees.

Assignees

• Apple Inc

Inventors

• Choi Jaein
• Tang Hairong
• Wong Gloria
• Kang Sunggu
• Lee Younggu
• Park Gwanwoo
• Huang Chun-Yao
• Lin Andrew
• Lo Cheuk Chi
• Dorjgotov Enkhamgalan
• Slootsky Michael
• Liu Rui
• Chang Wendi
• Chen Cheng
• Fujino Yusuke

Classifications

• H10K50/19

  Tandem OLEDs · CPC title

• H10K59/131

  Interconnections, e.g. wiring lines or terminals · CPC title

• H10K50/131

  with spacer layers between the electroluminescent layers · CPC title

• H10K59/122 Primary

  Pixel-defining structures or layers, e.g. banks · CPC title

• H10K2102/351

  Thickness · CPC title