Method of manufacturing display device Including Photoluminescence measurement

• US 10,580,825 B2
• Filed: 12/21/2018
• Issued: 03/03/2020
• Est. Priority Date: 03/08/2017
• Status: Active Grant

• Current Assignee: PlayNitride Display Co., Ltd.
• Original Assignee: PlayNitride Inc.
• Inventors: Lai, Yu-Hung
• Primary Examiner(s): Garces, Nelson
• Application Number:
  US16/230,629
• Publication Number:
  US 20190115390A1
• Time in Patent Office: 438 Days
• CPC Class Codes: H01L 22/12 for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions electrical measurement of diffusions H01L22/14
• CPC Class Codes: H01L 22/20 Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 27/156 two-dimensional arrays
• CPC Class Codes: H01L 33/025 Physical imperfections, e.g. particular concentration or distribution of impurities
• 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 33/14 with a carrier transport control structure, e.g. highly-doped semiconductor layer or current-blocking structure
• CPC Class Codes: H01L 33/22 Roughened surfaces, e.g. at the interface between epitaxial layers
• CPC Class Codes: H10K 59/352 the areas of the RGB subpixels being different
• CPC Class Codes: H10K 59/353 characterised by the geometrical arrangement of the RGB subpixels

Abstract

Disclosed are a method of manufacturing display device, an epitaxial wafer and a display device that includes a display substrate, a first sub pixel unit and a second sub pixel unit. The first sub pixel unit and the second sub pixel unit belong to same color type. The first sub pixel unit and the second sub pixel unit are formed from an epitaxial structure on the epitaxial wafer. The first sub pixel unit and the second sub pixel unit are formed and transferred to the display substrate from the epitaxial wafer. A first light emitting area of the first sub pixel unit and a second light emitting area of the second sub pixel unit are related to at least the photoluminescence measurement result of the epitaxial wafer.

Claims

1. A method of manufacturing display device, comprising:

providing an epitaxial structure;

obtaining a photoluminescence measurement result of the epitaxial structure, wherein the photoluminescence measurement result comprises a plurality of measured peak wavelengths corresponding to different regions on the epitaxial structure;

defining a non-deviation region and a deviation region of the epitaxial structure according to the photoluminescence measurement result, wherein the measured peak wavelength corresponding to the non-deviation region is equal to a standard peak wavelength or within a standard peak wavelength range, and the measured peak wavelength corresponding to the deviation region is unequal to the standard peak wavelength or out of the standard peak wavelength range;

forming a first sub epitaxial structure having a first luminous area in the non-deviation region of the epitaxial structure;

forming a second sub epitaxial structure having a second luminous area in the deviation region of the epitaxial structure, wherein the second luminous area is different from the first luminous area; and

forming two sub pixel units of the same color type on a display substrate by transferring two LED chips, which are formed respectively from the first sub epitaxial structure and the second sub epitaxial structure of the epitaxial structure, on the display substrate.

2. The method of manufacturing display device according to claim 1, wherein the two sub pixel units are a first sub pixel unit and a second sub pixel unit, respectively,

when the measured peak wavelength corresponding to the first sub pixel unit is larger than an upper limitation of a reference wavelength range, the first luminous area of the first sub pixel unit is determined as smaller than a standard area;

and

when the measured peak wavelength corresponding to the first sub pixel unit is smaller than a lower limitation of the reference wavelength range, the first luminous area of the first sub pixel unit is determined as larger than the standard area.

3. The method of manufacturing display device according to claim 2, wherein the first sub pixel unit is driven in a driving current to generate first emitted light, the second sub pixel unit is driven in the same driving current to generate second emitted light, and a difference between the peak wavelength of the first emitted light and the peak wavelength of the second emitted light is less than a first predetermined threshold.

4. The method of manufacturing display device according to claim 3, wherein the first predetermined threshold is not larger than 2 nm.

5. The method of manufacturing display device according to claim 3, wherein a current density of the first sub pixel unit and a current density of the second sub pixel unit range from 0.001 A/cm² to 5 A/cm².

6. The method of manufacturing display device according to claim 1, wherein the two sub pixel units belong to two different pixel units.