Full-color LED display using ultra-thin LED element and method for manufacturing thereof

Patent metadata

Field	Value
Publication number	US-12266740-B2
Application number	US-202117564740-A
Country	US
Kind code	B2
Filing date	Dec 29, 2021
Priority date	Mar 25, 2021
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

The present disclosure relates to a full-color light-emitting diode (LED) display, and more particularly, to a full-color LED display using an ultra-thin LED element and a manufacturing method thereof.

First claim

What is claimed is:

1. A full-color light-emitting diode (LED) display, comprising:
a lower electrode line including a first electrode on which a plurality of sub-pixel sites are formed;
a plurality of ultra-thin LED elements emitting light of substantially the same color, which are disposed so that at least two thereof are provided in each of the sub-pixel sites, and each of which comprises a first conductive semiconductor layer which is an n-type III-nitride semiconductor layer, a photoactive layer, a second conductive semiconductor layer which is an p-type III-nitride semiconductor layer, and at least one film of a hole pushing film and an electron pushing film, has a ratio, between a thickness, which is a stacking direction of layers, and a length of a major axis in a cross section perpendicular to the stacking direction, of 1:0.5 to 1.5, and is disposed upright on the first electrode in the stacking direction of the layers,
wherein the hole pushing film is configured to surround exposed side surfaces of the second conductive semiconductor layer, or the exposed side surfaces of the second conductive semiconductor layer and exposed side surfaces of at least a portion of the photoactive layer, and move holes at a surface side of the exposed side surface toward a center, and wherein the electron pushing film is configured to surround exposed side surfaces of the first conductive semiconductor layer and move electrons at a surface side of the exposed side surface toward a center;
an upper electrode line including a second electrode disposed on the plurality of ultra-thin LED elements; and
a color conversion layer patterned on the second electrode corresponding to the sub-pixel site so that each sub-pixel site becomes a sub-pixel site expressing one of blue, green, and red colors.

2. The full-color LED display of claim 1 , further comprising an alignment-inducing layer configured to allow the ultra-thin LED element to be disposed upright in a thickness direction, and formed on one side of the ultra-thin LED element in the thickness direction and on one side or both sides of the sub-pixel site in the first electrode,
wherein the alignment-inducing layer is a magnetic layer, a charge layer, or a bonding layer.

3. The full-color LED display of claim 1 , wherein the ultra-thin LED element has a maximum surface area of 16 μm 2 or less.

4. The full-color LED display of claim 1 , wherein the ultra-thin LED element has a thickness of 2.7 μm or less.

5. The full-color LED display of claim 1 , wherein in the ultra-thin LED element,
an electron delay layer is further included on a surface opposite to one surface of the first conductive semiconductor layer adjacent to the photoactive layer so that the number of electrons and holes recombined in the photoactive layer is balanced.

6. The full-color LED display of claim 5 , wherein the electron delay layer includes one or more selected from the group consisting of CdS, GaS, ZnS, CdSe, CaSe, ZnSe, CdTe, GaTe, SiC, ZnO, ZnMgO, SnO 2 , TiO 2 , In 2 O 3 , Ga 2 O 3 , Si, polyparaphenylene vinylene, derivatives thereof, polyaniline, poly (3-alkylthiophene), and poly (paraphenylene).

7. The full-color LED display of claim 5 , wherein
the electron delay layer is a III-nitride semiconductor having a lower doping concentration than the first conductive semiconductor layer.

8. The full-color LED display of claim 1 , further comprising a protective film surrounding exposed side surfaces of the ultra-thin LED element.

9. The full-color LED display of claim 1 , wherein the ultra-thin LED element includes both the hole pushing film and the electron pushing film, wherein the electron pushing film is provided as an outermost film configured to surround side surfaces of the first conductive semiconductor layer, the photoactive layer, and the second conductive semiconductor layer.

10. The full-color LED display of claim 1 , wherein the light color is blue, white, or ultraviolet (UV).

Assignees

• Univ Kookmin Ind Acad Coop Found

Inventors

• Do Young Rag

Classifications

• H10W99/00

  Subject matter not provided for in other groups of this subclass · CPC title

• H10W72/0198

  batch processes · CPC title

• H10W72/07331

  Connecting techniques · CPC title

• H10W72/07336

  Soldering or alloying · CPC title

• H10W72/073

  of die-attach connectors · CPC title