Methods of fabricating OLED panel with inorganic pixel encapsulating barrier

Patent metadata

Field	Value
Publication number	US-11690254-B2
Application number	US-202218049825-A
Country	US
Kind code	B2
Filing date	Oct 26, 2022
Priority date	Sep 4, 2020
Publication date	Jun 27, 2023
Grant date	Jun 27, 2023

Abstract

Embodiments described herein relate to sub-pixel circuits and methods of forming sub-pixel circuits that may be utilized in a display such as an organic light-emitting diode (OLED) display. The device includes a plurality of sub-pixels, each sub-pixel of the plurality of sub-pixels defined by adjacent pixel-defining layer (PDL) structures with inorganic overhang structures disposed on the PDL structures, each sub-pixel having an anode, organic light-emitting diode (OLED) material disposed on the anode, and a cathode disposed on the OLED material. The device is made by a process including the steps of: depositing the OLED material and the cathode by evaporation deposition, and depositing an encapsulation layer disposed over the cathode.

First claim

What is claimed is:

1. A method of forming a device, comprising:
positioning a substrate having:
an anode,
a first opening of a first sub-pixel defined by adjacent first inorganic overhang structures disposed over adjacent pixel-defining layer (PDL) structures disposed over the substrate;

depositing, at an OLED angle θ OLED defined using the first inorganic overhang structures, a first OLED material over a first portion and a second portion of the substrate, the first portion corresponding to the first sub-pixel and the second portion corresponding to a second sub-pixel;
depositing, at a cathode angle θ cathode defined using the first inorganic overhang structures, a first cathode over the first portion and the second portion of the substrate, wherein the first inorganic overhang structures are used in defining deposition angles of the OLED angle θ OLED and the cathode angle θ cathode ;
depositing a first encapsulation layer over the first cathode and over the first portion and the second portion of the substrate such that the first sub-pixel comprises:
the first OLED material having an OLED edge extending under first and second extensions of an upper portion of the first inorganic overhang structures; and
the first cathode extending under the first and second extensions of the upper portion of the first inorganic overhang structures and past the OLED edge; and

removing the first OLED material, the first cathode, and the first encapsulation layer over the second portion.

2. The method of claim 1 , further comprising:
disposing a second opening of a second sub-pixel defined by adjacent second inorganic overhang structures disposed over the PDL structures disposed over the substrate;
depositing, at the OLED angle θ OLED defined using the second inorganic overhang structures, a second OLED material over the first portion and the second portion of the substrate;
depositing, at a cathode angle θ cathode defined using the second inorganic overhang structures, a second cathode over the first portion and the second portion of the substrate, wherein the second inorganic overhang structures are used in defining deposition angles of the OLED angle θ OLED and the cathode angle θ cathode ;
depositing a second encapsulation layer over the second cathode and over the first portion and the second portion of the substrate such that the second sub-pixel comprises:
the second OLED material having an OLED edge extending under first and second extensions of an upper portion of the second inorganic overhang structures; and

removing the second OLED material, the second cathode, and the second encapsulation layer over the first portion.

3. The method of claim 2 , wherein the lower portion comprises a first composition.

4. The method of claim 3 , wherein each of the first inorganic overhang structure comprises one of:
the upper portion of a non-conductive inorganic material and the lower portion of a conductive inorganic material, the first cathode extending under an underside edge and contacting the conductive inorganic material of the first composition of the lower portion at one of first and second sidewalls of the lower portion;
the upper portion of the conductive inorganic material and the lower portion of the conductive inorganic material, the first cathode extending under the underside edge and contacting the conductive inorganic material of the first composition of the lower portion at one of the first and second sidewalls of the lower portion;
the upper portion of the non-conductive inorganic material, the lower portion of the non-conductive inorganic material, and an assistant cathode disposed under the lower portion, the cathode extending under the underside edge and contacting a top surface of the assistant cathode of the first composition; or
the upper portion of the conductive inorganic material, the lower portion of the non-conductive inorganic material, and the assistant cathode disposed under the lower portion, the cathode extending under the underside edge and contacting the top surface of the assistant cathode of the first composition.

5. The method of claim 4 , wherein the first OLED material and the first cathode are deposited over:
a first well of the first sub-pixel defined by the first inorganic overhang structures of the first sub-pixel; and
an upper portion layer having a second composition disposed over the second sub-pixel to be formed, wherein:
the first OLED material is disposed over one of the PDL structures of the first sub-pixel; and
the first cathode extends under the underside edge and contacts the lower portion having the first composition at the first and second sidewalls of the lower portion or the top surface of the assistant cathode of the first inorganic overhang structures of the first sub-pixel.

6. The method of claim 4 , wherein the first OLED material and the first cathode are deposited over:
a first well of the first sub-pixel defined by the first inorganic overhang structures of the first sub-pixel, wherein:
the first OLED material is disposed over one of the PDL structures of the first sub-pixel; and
the first cathode extends under the underside edge of one of the first inorganic overhang structures and contacts the lower portion having the first composition at the first and second sidewalls of the lower portion or the top surface of the assistant cathode of the first inorganic overhang structures of the first sub-pixel.

7. The method of claim 4 , wherein:
the second OLED material and the second cathode are deposited over a second well of the second sub-pixel defined by the second inorganic overhang structures of the second sub-pixel, wherein:
the second OLED material is disposed over one of the PDL structures of the second sub-pixel; and
the second cathode extends under the underside edge and contacts the lower portion having the first composition at the first and second sidewalls or the top surface of the assistant cathode of the second inorganic overhang structures of the second sub-pixel.

8. The method of claim 4 , wherein:
the first encapsulation layer extends:
to contact the first composition at the first and second sidewalls of the lower portion of the first inorganic overhang structures of the first sub-pixel;
to contact a second composition of the upper portion of the first inorganic overhang structures at an underside surface of the first and second extensions of the first inorganic overhang structures of the first sub-pixel; and
over at least a first portion of an uppermost surface of the upper portion of the first inorganic overhang structures of the first sub-pixel.

9. The method of claim 8 , further comprising:
depositing a second encapsulation layer over the second cathode of a second sub-pixel, wherein the second encapsulation layer extends:
to contact the first composition at the first and second sidewalls of the lower portion of the second inorganic overhang structures of the second sub-pixel;
to contact the second composition of the upper portion of the second inorganic overhang structures at the underside surface of the first and second extensions of the second inorganic overhang structures of the second sub-pixel; and
over at least a second portion of the uppermost surface of the upper portion of the second inorganic overhang structures of the second sub-pixel.

10. The method of claim 9 , further comprising:
depositing a first plug over the first encapsulation layer, the first plug having a first plug transmittance that is matched or substantially matched to a first OLED transmittance of the first OLED material of the first sub-pixel; and
depositing a second plug over the second encapsulation layer, the secon

Assignees

• Applied Materials Inc

Inventors

• Choung Ji Young
• Haas Dieter
• Lin Yu-Hsin
• Lee Jungmin
• Yoo Seong Ho
• Kim Si Kyoung

Classifications

• H10K50/844 Primary

  Encapsulations · CPC title

• H10K71/00

  Manufacture or treatment specially adapted for the organic devices covered by this subclass · CPC title

• H10K50/84

  Passivation; Containers; Encapsulations · CPC title

• H10K59/873

  Encapsulations · CPC title

• H10K59/1315

  comprising structures specially adapted for lowering the resistance · CPC title