Fabrication method for emissive display with light management system

• US 10,381,332 B2
• Filed: 01/16/2018
• Issued: 08/13/2019
• Est. Priority Date: 10/31/2014
• Status: Active Grant

• Current Assignee: Elux Inc.
• Original Assignee: Elux Inc.
• Inventors: Ulmer, Kurt, Schuele, Paul J., Sasaki, Kenji, Lee, Jong-Jan
• Primary Examiner(s): Tran, Tan N
• Application Number:
  US15/872,749
• Publication Number:
  US 20180145057A1
• Time in Patent Office: 574 Days
• Field of Search: 257 98, 257 99, 257100
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2933/0033 relating to semiconductor body packages
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• CPC Class Codes: H01L 2933/0058 relating to optical field-shaping elements
• CPC Class Codes: H01L 2933/0066 relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

A method is provided for fabricating an emissive display substrate with a light management system. The method provides a transparent first substrate with a top surface and forms a plurality of emissive element wells. The well sidewalls are formed from a light absorbing material or a light reflector material. In one aspect, a light blocking material film layer is formed overlying the first substrate top surface, and the emissive element sidewalls are formed in the light blocking material film layer. In another aspect, a transparent second substrate is formed overlying the first substrate top surface. Then, the emissive element wells are formed in the second substrate with via surfaces, and the light blocking material is deposited overlying the well via surfaces. Additionally, the light blocking material may be formed on the bottom surface of each well. An emissive display substrate with light management system is provided below.

Claims

1. A method for fabricating an emissive display substrate with a light management system, the method comprising:

providing a transparent first substrate with a top surface;

forming a transparent second substrate overlying the first substrate top surface;

forming a plurality of emissive element wells in the second substrate with via surfaces;

depositing a light blocking material overlying the well via surfaces;

forming emissive element well sidewalls from the light blocking material; and

,

using a fluidic assembly process to populate the wells with emissive elements.

2. The method of claim 1 wherein the light blocking material is selected from the group consisting of a light absorbing material and a light reflector material.

3. The method of claim 2 wherein the light absorber material is selected from a group consisting of a black polymer resin, a black photoresist, a material comprising carbon black, and a material comprising graphene oxide.

4. The method of claim 2 wherein the light reflector material is selected from a group consisting of aluminum, titanium, silver, tin, indium, nickel, and gold.

5. The method of claim 1 wherein providing the first substrate includes providing a substrate with a first plurality of electrical interfaces formed on the top surface;

and,

wherein forming the emissive element wells includes etching the second substrate to expose the first plurality of electrical interfaces, forming an electrical interface on each well bottom surface.

6. The method of claim 5 wherein forming well sidewalls from the light blocking material includes:

conformally depositing the light absorbing blocking material overlying the second substrate top surface and filling the wells;

patterning the light blocking material to avoid the electrical interface formed on the well bottom surface; and

,

etching the light absorbing blocking material to expose the electric interface on each well bottom surface.

7. The method of claim 1 wherein forming the emissive element wells includes forming emissive wells with sloped via surfaces;

and,

wherein forming emissive element well sidewalls includes forming sloped emissive element well sidewalls.

8. A method for managing the direction of light emitted from an emissive display substrate, the method comprising:

providing a transparent substrate and a plurality of emissive element wells;

forming light blocking material well sidewalls;

populating the wells with emissive elements using a fluidic assembly process; and

,

in response to the light blocking material sidewalls, preventing the propagation of light between adjacent wells.

9. A method for fabricating an emissive display substrate with a light management system, the method comprising:

providing a transparent first substrate with a top surface;

forming a light blocking material film layer overlying the first substrate top surface;

forming a plurality of emissive element wells in the light blocking material film layer; and

,

using a fluidic assembly process, populating the emissive element wells with emissive elements.

10. The method of claim 9 wherein the light blocking material is selected from the group consisting of a light absorbing material and a light reflector material.

11. The method of claim 10 wherein the light absorber material is selected from a group consisting of a black polymer resin, a black photoresist, a material comprising carbon black, and a material comprising graphene oxide.

12. The method of claim 10 wherein the light reflector material is selected from a group consisting of aluminum, titanium, silver, tin, indium, nickel, and gold.

13. The method of claim 9 wherein forming the plurality of emissive element wells in the light blocking material film layer includes forming the light blocking material on a bottom surface of each well.

14. The method of claim 13 wherein providing the first substrate includes providing a substrate with a plurality of electrical interfaces formed on the top surface;

the method further comprising;

patterning the light blocking material to avoid the electrical interface formed on the well bottom surface; and

,

etching the light blocking film layer to expose the first plurality of electrical interfaces, forming an electrical interface on each well bottom surface.

15. The method of claim 9 wherein forming the emissive element wells includes forming emissive element wells with sloped via surfaces;

and,

wherein forming emissive element well sidewalls includes forming sloped emissive element well sidewalls.

16. A method for fabricating an emissive display substrate with a light management system, the method comprising:

providing a transparent first substrate with a top surface;

forming emissive element wells in the first substrate with via surfaces;

depositing a light blocking material overlying the well via surfaces; and

,

using a fluidic assembly process, populating the emissive element wells with emissive elements.

17. The method of claim 16 wherein the light blocking material is selected from the group consisting of a light absorbing material and a light reflector material.

18. The method of claim 17 wherein the light absorber material is selected from a group consisting of a black polymer resin, a black photoresist, a material comprising carbon black, and a material comprising graphene oxide.

19. The method of claim 17 wherein the light reflector material is selected from a group consisting of aluminum, titanium, silver, tin, indium, nickel, and gold.

20. The method of claim 16 further comprising:

forming the light blocking material on a bottom surface of each well.

21. The method of claim 16 wherein depositing the light blocking material overlying the well via surfaces includes:

conformally depositing a light blocking material film layer;

patterning the light blocking material to avoid an electrical interface formed on each well bottom surface; and

,

etching the light blocking film layer to expose the first plurality of electrical interfaces, forming an electrical interface on each well bottom surface.

22. The method of claim 16 wherein forming the emissive element wells includes forming emissive element wells with sloped via surfaces;

and,

wherein forming emissive element well sidewalls includes forming sloped emissive element well sidewalls.

23. A method for fabricating an emissive display substrate with a light management system, the method comprising:

providing a transparent substrate with a top surface;

forming a plurality of emissive element wells in the substrate top surface with via surfaces;

using a fluidic assembly process to populate the wells with emissive elements;

subsequent to populating the wells with the emissive elements, depositing a light blocking material overlying the substrate top surface; and

,

pattern etching the light blocking material to expose emissive element top surfaces.

24. The method of claim 23 wherein depositing the light blocking material includes forming emissive element well sidewalls from the light blocking material.