Crystalline color-conversion device

• US 10,164,404 B2
• Filed: 10/16/2017
• Issued: 12/25/2018
• Est. Priority Date: 06/09/2015
• Status: Active Grant

• Current Assignee: X Display Company Technology Limited (Sensinnovat BVBA)
• Original Assignee: X-Celeprint Limited
• Inventors: Bower, Christopher, Meitl, Matthew, Cok, Ronald S.
• Primary Examiner(s): Chin, Edward
• Application Number:
  US15/785,105
• Publication Number:
  US 20180041005A1
• Time in Patent Office: 435 Days
• Field of Search: 257E33008, 257 13, 257E21499, 257E21502, 257E29168, 257E33059, 257103, 257 14, 257184, 257200, 257 76, 257 88, 257 94, 438 27, 438107, 438126, 438127, 438 28, 438 37, 438 44
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2933/0041 relating to wavelength conversion elements
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/505 characterised by the shape, e.g. plate or foil
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/508 having a non-uniform spatial arrangement or non-uniform concentration, e.g. patterned wavelength conversion layer, wavelength conversion layer with a concentration gradient of the wavelength conversion material
• CPC Class Codes: H01S 3/0915 by incoherent light
• CPC Class Codes: H01S 5/02257 using windows, e.g. specially adapted for back-reflecting light to a detector inside the housing
• CPC Class Codes: H01S 5/02326 Arrangements for relative positioning of laser diodes and optical components, e.g. grooves in the mount to fix optical fibres or lenses
• CPC Class Codes: H01S 5/02345 Wire-bonding
• CPC Class Codes: H01S 5/041 Optical pumping
• CPC Class Codes: H01S 5/32 comprising PN junctions, e.g. hetero- or double- heterostructures H01S5/34, H01S5/36 take precedence
• CPC Class Codes: H01S 5/32341 blue laser based on GaN or GaP
• CPC Class Codes: H01S 5/4025 Array arrangements, e.g. constituted by discrete laser diodes or laser bar H01S5/42 takes precedence

Abstract

According to an embodiment, a crystalline color-conversion device includes an electrically driven first light emitter, for example a blue or ultraviolet LED, for emitting light having a first energy in response to an electrical signal. An inorganic solid single-crystal direct-bandgap second light emitter having a bandgap of a second energy less than the first energy is provided in association with the first light emitter. The second light emitter is electrically isolated from, located in optical association with, and physically connected to the first light emitter so that in response to the electrical signal the first light emitter emits first light that is absorbed by the second light emitter and the second light emitter emits second light having a lower energy than the first energy.

Claims

1. A method of making a crystalline color-conversion device, comprising:

providing an electrically driven first light emitter for emitting first light having a first energy in response to an electrical current signal, wherein the electrically driven first light emitter is electrically connected to two or more electrical contacts that provide the electrical current signal to the first light emitter;

providing an optically driven inorganic solid single-crystal direct-bandgap second light emitter having a bandgap of a second energy less than the first energy; and

micro transfer printing the second light emitter from a source substrate onto the first light emitter or micro transfer printing the first light emitter from a source substrate onto the second light emitter so that the second light emitter (i) is electrically isolated from the first light emitter so that current passing through the first light emitter does not pass through the second light emitter, (ii) is located in optical association with the first light emitter, and (iii) is located within 0 to 250 microns of the first light emitter such that in response to the electrical signal the first light emitter emits first light that is absorbed by the second light emitter and the second light emitter emits second light having a lower energy than the first energy.

2. The method of claim 1, wherein the first light emitter and the second light emitter form a light-emitting conversion structure and the method comprises micro-transfer printing the light-emitting conversion structure from a source substrate onto a display substrate.

3. The method of claim 1, comprising forming an inorganic solid single-crystal direct-bandgap layer on a source substrate and disposing the first light emitter onto the inorganic solid single-crystal direct-bandgap layer.

4. The method of claim 3, comprising etching the layer to form a plurality of spatially separated crystalline color-conversion devices on the source substrate.

5. The method of claim 4, comprising micro transfer printing the crystalline color-conversion devices from the source substrate to a display substrate.

6. The method of claim 1, comprising providing an inorganic solid single-crystal direct-bandgap source substrate and disposing the first light emitters onto the source substrate.

7. The method of claim 6, comprising etching the source substrate to form a plurality of spatially separated crystalline color-conversion devices.

8. The method of claim 7, comprising micro transfer printing the plurality of crystalline color-conversion devices from the source substrate to a display substrate.