Device with multiple vertically separated terminals and methods for making the same

• US 10,643,982 B2
• Filed: 06/14/2019
• Issued: 05/05/2020
• Est. Priority Date: 12/22/2017
• Status: Active Grant

• Current Assignee: X Development LLC (Alphabet Inc.)
• Original Assignee: X Development LLC (Alphabet Inc.)
• Inventors: Schubert, Martin Friedrich, Grundmann, Michael Jason
• Primary Examiner(s): Geyer, Scott B
• Application Number:
  US16/442,029
• Publication Number:
  US 20190312082A1
• Time in Patent Office: 326 Days
• CPC Class Codes: F21V 1/00 Shades for light sources , i.e. lampshades for table, floor, wall or ceiling lamps
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 27/0207 Geometrical layout of the components, e.g. computer aided design; custom LSI, semi-custom LSI, standard cell technique
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 2933/0016 relating to electrodes
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01L 33/387 with a plurality of electrode regions in direct contact with the semiconductor body and being electrically interconnected by another electrode layer
• CPC Class Codes: H01L 33/486 adapted for surface mounting
• 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
• CPC Class Codes: H05B 33/06 Electrode terminals
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H05B 33/145 Arrangements of the electroluminescent material
• CPC Class Codes: H05B 33/28 of translucent electrodes
• CPC Class Codes: H05B 45/30 Driver circuits

Abstract

A light emitting device that includes: a plurality of light emitting elements arranged at different locations in a common plane, each light emitting element including: at least one layer of a semiconductor material; a first electrical terminal located at a first location; a second electrical terminal located at a second location; and a third electrical terminal located at a third location; a first electrode layer including one or more electrodes; a second electrode layer including one or more electrodes; a third electrode layer including one or more electrodes; a first electrically insulating layer disposed between the plurality of light emitting elements and also disposed between the first and second electrode layers; and a second electrically insulating layer disposed between the plurality of light emitting elements and also disposed between the second and third electrode layers.

Claims

1. A process for producing a light emitting device, comprising:

placing a plurality of light emitting elements on a surface of a substrate at different locations in a common plane, each light emitting element comprising;

at least one layer of a semiconductor material;

a first electrical terminal for providing charge carriers to a first portion of the light emitting element, the first electrical terminal being located at a first location along an axis perpendicular to the common plane;

a second electrical terminal for providing charge carriers to a second portion of the light emitting element, the second electrical terminal being located at a second location along the axis perpendicular to the common plane different from the first location; and

a third electrical terminal for providing charge carriers to a third portion of the light emitting element, the third electrical terminal being located at a third location along the axis perpendicular to the common plane different from the first and second locations;

forming a first electrode layer comprising one or more electrodes each being in electrical contact with the first electrical terminal of one or more of the plurality of light emitting elements;

forming a first electrically insulating layer over the first electrode layer; and

forming a second electrode layer comprising one or more electrodes each being in electrical contact with the second electrical terminal of one or more of the plurality of light emitting elements.

2. The process of claim 1, wherein widths of the one or more electrodes of the first electrode layer and the second electrode layer are larger than a lateral placement accuracy achieved during the placing of the plurality of light emitting elements on the surface of the substrate at different locations in the common plane.

3. The process of claim 1, wherein widths of the one or more electrodes of the first electrode layer and the second electrode layer are larger than dimensions of the light emitting elements in the common plane.

4. The process of claim 1, wherein the substrate is an active matrix backplane comprising a third electrode layer comprising one or more electrodes each configured to be in electrical contact with the third electrical terminal of one or more of the plurality of light emitting elements, and

wherein the process further comprises:

prior to the forming a first electrode layer, forming a second electrically insulating layer over the third electrode layer.

5. The process of claim 1, further comprising:

prior to the placing a plurality of light emitting elements on a surface of a substrate, forming a third electrode layer comprising one or more electrodes each being in electrical contact with the third electrical terminal of one or more of the plurality of light emitting elements; and

prior to the forming a first electrode layer, forming a second electrically insulating layer over the third electrode layer.

6. The process of claim 1, wherein the placing a plurality of light emitting elements on a surface of a substrate comprises:

performing parallel transfer of the plurality of light emitting elements.

7. The process of claim 1, wherein the placing a plurality of light emitting elements on a surface of a substrate comprises:

performing a self-assembly of the plurality of light emitting elements.

8. The process of claim 1, further comprising:

after the placing a plurality of light emitting elements on a surface of a substrate, performing a reflow step to mechanically attach the plurality of light emitting elements on the surface of the substrate.

9. The process of claim 1, further comprising:

placing a plurality of non-light emitting elements on the surface of the substrate at different locations in the common plane, the plurality of non-light emitting elements comprising at least one of photosensor, voltage driver circuit, current driver circuit, RF circuit, antenna, logic circuit, or memory.