OPTOELECTRONIC DEVICE WITH LIGHT-EMITTING DIODES

• US 20190319066A1
• Filed: 12/28/2017
• Published: 10/17/2019
• Est. Priority Date: 12/29/2016
• Status: Active Grant

• Current Assignee: Aledia
• Original Assignee: Aledia
• Inventors: Tan, Wei Sin, Gilet, Philippe
• Granted Patent: US 10,916,579 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 29/0676 oriented perpendicular or at an angle to a substrate
• CPC Class Codes: H01L 29/125 Quantum wire structures
• CPC Class Codes: H01L 29/15 Structures with periodic or quasi periodic potential variation, e.g. multiple quantum wells, superlattices such structures applied for the control of light G02F1/017, applied in semiconductor lasers H01S5/34
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 relating to encapsulations
• 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 33/18 within the light emitting region
• CPC Class Codes: H01L 33/24 of the light emitting region, e.g. non-planar junction
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/56 Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H10K 50/115 comprising active inorganic nanostructures, e.g. luminescent quantum dots

Abstract

An optoelectronic device including light-emitting diodes (LED), each light-emitting diode including a semiconductor element corresponding to a nanowire, a microwire, and/or a nanometer- or micrometer-range pyramidal structure, and a shell at least partially covering the semiconductor element and adapted to emit a radiation and for each light-emitting diode, a photoluminescent coating including a single quantum well, multiple quantum wells or an heterostructure, covering at least part of the shell and in contact with the shell or with the semiconductor element and adapted to convert by optical pumping the radiation emitted by the shell into another radiation.

Claims

1. An optoelectronic device comprising:

light-emitting diodes (LED), each light-emitting diode comprising a semiconductor element corresponding to a nanowire, a microwire, and/or a nanometer- or micrometer-range pyramidal structure, and a shell at least partially covering the semiconductor element and adapted to emit a radiation; and

for each light-emitting diode, a photoluminescent coating comprising a single quantum well, multiple quantum wells or an heterostructure, covering at least part of the shell and in contact with the shell or with the semiconductor element and adapted to convert by optical pumping the radiation emitted by the shell into another radiation.

2. The optoelectronic device of claim 1, wherein the light-emitting diodes (LED) are adapted to emit a first radiation at a first wavelength and wherein the photoluminescent coatings comprise first photoluminescent coatings adapted to convert by optical pumping the first radiation into a second radiation at a second wavelength, second photoluminescent coatings adapted to convert by optical pumping the first radiation into a third radiation at a third wavelength and third photoluminescent coatings adapted to convert by optical pumping the first radiation into a fourth radiation at a fourth wavelength.

3. The optoelectronic device of claim 1, wherein each semiconductor element comprises lateral sides and a top face, and wherein the photoluminescent coatings and the shells cover the lateral sides and top faces of the semiconductor elements.

4. The optoelectronic device of claim 1, wherein each semiconductor element comprises lateral sides and a top face, wherein the shells cover the lateral sides of the semiconductor elements and do not cover the top faces of the semiconductor elements, and wherein the photoluminescent coatings cover the top faces of the semiconductor elements and do not cover the lateral sides of the semiconductor elements.

5. The optoelectronic device of claim 1, comprising, for each light-emitting diode (LED), an electrically conductive layer in contact with the shell.

6. The optoelectronic device of claim 5, wherein, for each light-emitting diode (LED), the conductive layer is covered by a reflective layer.

7. The optoelectronic device of claim 5, wherein the conductive layer comprises a tunnel junction structure.

8. The optoelectronic device of claim 2, further comprising walls resting on the substrate, at least partially made of a reflecting material at least for the second, third and fourth radiations and surrounding the light-emitting diodes (LED).

9. The optoelectronic device of claim 2, further comprising a filter covering the photoluminescent coatings and adapted to block the first radiation and to give way to the second, third and fourth radiations.

10. The optoelectronic device of claim 2, wherein the first wavelength is in the range from 360 nm to 430 nm, wherein the second wavelength is in the range from 440 nm to 490 nm, wherein the third wavelength is in the range from 510 nm to 570 nm, and wherein the fourth wavelength is in a range from 610 nm to 720 nm.

11. The optoelectronic device of claim 2, wherein the photoluminescent coatings further comprise fourth photoluminescent coatings adapted to convert by optical pumping the first radiation into a fifth radiation at a fifth wavelength.

12. The optoelectronic device of claim 11, wherein the fifth wavelength is in the range from 570 nm to 600 nm.

13. A method of manufacturing an optoelectronic device of claim 1, comprising the successive steps of:

a) forming the light-emitting diodes (LED); and

b) forming the photoluminescent coatings.

14. The method of claim 13, comprising, before step b), the formation of an electrically conductive layer covering the shells, and, before step b), the withdrawal of the conductive layers and the shells at the tops of the semiconductor elements, and the formation of the photoluminescent coatings at the tops of the semiconductor elements.