Micro-nanofin LED element and method for producing same

Patent metadata

Field	Value
Publication number	US-12439739-B2
Application number	US-202117997265-A
Country	US
Kind code	B2
Filing date	Apr 27, 2021
Priority date	Apr 27, 2020
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

The present invention relates to an LED element, more particularly, to a micro-nanofin LED element and a method for manufacturing the same.

First claim

The invention claimed is:

1. A method for manufacturing a micro-nanofin LED element, comprising the steps of:
(1) preparing an LED wafer in which a first conductive semiconductor layer, a photoactive layer, and a second conductive semiconductor layer are sequentially stacked;
(2) forming an electrode layer or a polarization inducing layer patterned so that regions having different electrical polarities are adjacent to each other on the second conductive semiconductor layer of the LED wafer;
(3) forming a plurality of micro-nanofin LED structures by etching the LED wafer in a thickness direction so that each element has a plane having a length and width of nano or micro size in which a thickness perpendicular to the plane is smaller than the length; and
(4) separating the plurality of micro-nanofin LED structures from the LED wafer.

2. The method according to claim 1 , wherein the polarization inducing layer in the step (2) is formed by including the steps of:
2-1) forming a first polarization inducing layer on the second conductive semiconductor layer;
2-2) etching the first polarization inducing layer in the thickness direction along a predetermined pattern; and
2-3) forming a second polarization inducing layer on an etched intaglio portion.

3. The method according to claim 1 , wherein the step (3) includes the steps of:
3-1) forming a mask pattern layer on an upper surface of the electrode layer or the polarization inducing layer so that each element has a planar shape having a length and width of nano or micro size;
3-2) forming the plurality of micro-nanofin LED structures by etching the first conductive semiconductor layer to a partial thickness in the thickness direction along a pattern of the mask pattern layer;
3-3) forming an insulating film to cover an exposed side surface of each of the plurality of micro-nanofin LED structures;
3-4) removing a portion of the insulting film formed on the upper portion of the first conductive semiconductor layer to expose an upper surface of the first conductive semiconductor layer between the adjacent micro-nanofin LED structures while not removing the insulating film covering side surfaces of the plurality of micro-nanofin LED structures;
3-5) forming the plurality of micro-nanofin LED structures in which a side portion of the first conductive semiconductor layer is exposed by further etching an exposed upper portion of the first conductive semiconductor layer in the thickness direction;
3-6) etching the first conductive semiconductor layer exposed in each of the micro-nanofin LED structures from both side surfaces in a width direction to a center; and
3-7) removing the mask pattern layer disposed on the upper portion of the electrode layer or the polarization inducing layer and the insulating film covering the side surface.

4. The method according to claim 1 , further comprising, between the steps (3) and (4), the step of (5) forming a protective film on the side surfaces of the plurality of micro-nanofin LED structures.

5. The method according to claim 1 , wherein a lower surface of the first conductive semiconductor layer of the micro-nanofin LED element separated in the step (4) has a protrusion having a predetermined width and thickness formed in a longitudinal direction of the element.

6. A micro-nanofin LED element which is a rod-type element having a plane having a length and width of nano or micro size in which a thickness perpendicular to the plan is smaller than the length, and in which a first conductive semiconductor layer, a photoactive layer, a second conductive semiconductor layer, and an electrode layer or a polarization inducing layer are sequentially stacked in a thickness direction,
wherein one of the first conductive semiconductor layer and the second conductive semiconductor layer includes a p-type GaN semiconductor layer, and the other includes an n-type GaN semiconductor layer, and
the p-type GaN semiconductor layer has a thickness of 10 to 350 nm, and the n-type GaN semiconductor layer has a thickness of 1000 to 3000 nm, and a thickness of the photoactive layer has a thickness of 30 to 200 nm.

7. The micro-nanofin LED element according to claim 6 , wherein the polarization inducing layer is configured so that electrical polarities of both ends of the element in a longitudinal direction are different from each other.

8. The micro-nanofin LED element according to claim 6 , wherein the length is 1000 to 10000 nm, and the thickness is 100 to 3000 nm.

9. The micro-nanofin LED element according to claim 6 , wherein a ratio of the length and thickness of the element is 3:1 or more.

10. The micro-nanofin LED element according to claim 6 , wherein the polarization inducing layer includes a first polarization inducing layer and a second polarization inducing layer that are disposed adjacent to each other in a longitudinal direction of the element and have different electrical polarities from each other.

11. The micro-nanofin LED element according to claim 10 , wherein the first polarization inducing layer is ITO, and the second polarization inducing layer is a metal or semiconductor.

12. The micro-nanofin LED element according to claim 6 , wherein an emission area of the micro-nanofin LED element exceeds twice an area of a vertical cross-section of the micro-nanofin LED element.

13. The micro-nanofin LED element according to claim 6 , wherein the micro-nanofin LED element is for use in an electric field array assembly in which the LED element is self-aligned on an electrode through an electric field induction arrangement.

14. The micro-nanofin LED element according to claim 6 , wherein a lower surface of the first conductive semiconductor layer of the micro-nanofin LED element has a protrusion having a predetermined width and thickness formed in a longitudinal direction of the element.

15. The micro-nanofin LED element according to claim 14 , wherein a width of the protrusion is formed to be 50% or less compared to the width of the micro-nanofin LED element.

Assignees

• Univ Kookmin Ind Acad Coop Found

Inventors

• Do Young Rag

Classifications

• H10H20/032

  of electrodes · CPC title

• H10H20/825

  containing nitrogen, e.g. GaN · CPC title

• H10H20/0137

  the light-emitting regions comprising nitride materials · CPC title

• H10H20/83

  Electrodes · CPC title

• H10H20/018 Primary

  Bonding of wafers · CPC title