Micro-light-emitting diode device and method for manufacturing the same

• US 9,825,200 B2
• Filed: 03/04/2016
• Issued: 11/21/2017
• Est. Priority Date: 05/13/2015
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Lin, Tsung-Yi, Chang, Cheng-Chieh
• Primary Examiner(s): Armand, Marc
• Assistant Examiner(s): Kilpatrick, Warren H
• Application Number:
  US15/060,885
• Publication Number:
  US 20160336486A1
• Time in Patent Office: 627 Days
• Field of Search: 257 82, 257 88, 257 98, 438 22, 438 24, 438 46
• CPC Class Codes: H01L 33/005 Processes
• CPC Class Codes: H01L 33/20 with a particular shape, e.g. curved or truncated substrate
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers

Abstract

A micro-light-emitting diode (micro-LED) device includes a first semiconductor layer, an active layer, and a second semiconductor layer. The first semiconductor layer includes a first bottom surface. The active layer is disposed on the first semiconductor layer. The second semiconductor layer disposed on the active layer includes a second bottom surface. A surface of the second semiconductor layer opposite to the active layer is a light-exiting surface of the micro-LED device. The second semiconductor layer has different thicknesses, in which a minimum thickness of the second semiconductor layer is located at an edge or at least one side of the second semiconductor layer. Vertical-projection zones of the first semiconductor layer, the active layer, and the second semiconductor layer on the first bottom surface are substantially the same.

Claims

1. A method for manufacturing a micro-light-emitting diode device comprising:

providing a first substrate;

depositing a mask layer on the first substrate;

patterning the mask layer to expose a portion of the first substrate;

etching the exposed portion of the first substrate to form a recess, and a depth at a center of the recess being greater than a depth at an edge of the recess;

removing the mask layer;

forming a micro-light-emitting diode device comprising;

depositing a second semiconductor layer on the recess;

depositing an active layer on the second semiconductor layer, wherein the recess is filled with a portion of the second semiconductor layer; and

depositing a first semiconductor layer on the active layer;

transferring and reversing the first substrate and the micro-light-emitting diode device to a second substrate, the first semiconductor layer of the micro-light-emitting diode device being connected to the second substrate;

etching the first semiconductor layer, the active layer and the second semiconductor layer in a same time to define a size of the micro-light-emitting diode device; and

removing the first substrate.

2. The method of claim 1, wherein the second semiconductor layer is deposited in the recess and fills and levels up the recess.

3. The method of claim 1, wherein the portion of the first substrate is etched to form a first shape, and the second semiconductor layer is deposited on the recess to form a light-exiting surface, the light-exiting surface has a second shape, and the first shape and the second shape are the same.

4. The method of claim 1, further comprising:

providing a panel, and forming at least one thin film transistor on the panel;

gripping the micro-light-emitting diode device to allow the micro-light-emitting diode device to be separated from the second substrate, and moving the micro-light-emitting diode device onto the thin film transistor; and

forming an electrode layer on the second semiconductor layer of the micro-light-emitting diode device.