US-12625366-B2 - Display device, augmented reality device including display device, and method of manufacturing display device

US12625366B2US 12625366 B2US12625366 B2US 12625366B2US-12625366-B2

Abstract

A display device includes: a plurality of light emitting elements including a first semiconductor layer, each of the plurality of light emitting elements including a second semiconductor layer provided under the first semiconductor layer and an active layer between the first semiconductor layer and the second semiconductor layer; a plurality of partition walls extending from the first semiconductor layer; and a plurality of color conversion layers provided on the plurality of light emitting elements in correspondence with the plurality of light emitting elements and spaced apart from each other by the plurality of partition walls, each of the plurality of color conversion layers including a first color conversion layer and a second color conversion layer stacked on the first color conversion layer.

Inventors

Kiho Kong
Junhee Choi
Junghun PARK
Eunsung Lee

Assignees

SAMSUNG ELECTRONICS CO., LTD.

Dates

Publication Date: 20260512
Application Date: 20220729
Priority Date: 20220110

Claims (19)

1 . A display device comprising: a plurality of light emitting elements including a first semiconductor layer, each of the plurality of light emitting elements including a second semiconductor layer provided under the first semiconductor layer and an active layer between the first semiconductor layer and the second semiconductor layer; a plurality of partition walls extending from the first semiconductor layer; and a plurality of color conversion layers provided on the plurality of light emitting elements in correspondence with the plurality of light emitting elements and spaced apart from each other by the plurality of partition walls, each of the plurality of color conversion layers including a first color conversion layer and a second color conversion layer stacked on the first color conversion layer, wherein the first semiconductor layer includes an upper surface, a lower surface opposite to the upper surface, the plurality of partition walls protruding and extending from the upper surface, and a plurality of opening areas provided between the plurality of partition walls, and wherein a material of the plurality of partition walls is the same as a material of the first semiconductor layer, and the plurality of partition walls extend in an integrated manner from the upper surface of the first semiconductor layer.
2 . The display device of claim 1 , wherein the active layer of each of the plurality of light emitting elements faces a corresponding opening area of the plurality of opening areas on the lower surface of the first semiconductor layer, and in each of the plurality of light emitting elements, the second semiconductor layer is provided under the active layer.
3 . The display device of claim 1 , further comprising a plurality of separation films respectively provided between active layers of adjacent light emitting elements of the plurality of light emitting elements and between second semiconductor layers of the adjacent light emitting elements.
4 . The display device of claim 1 , wherein the first color conversion layer of each of the plurality of color conversion layers is provided in a corresponding opening area of the plurality of opening areas on the upper surface of the first semiconductor layer, and the second color conversion layer of each of the plurality of color conversion layers is provided on the corresponding first color conversion layer and includes a material different from that of the first color conversion layer.
5 . The display device of claim 1 , further comprising a common electrode provided on an upper surface of each of the plurality of partition walls.
6 . The display device of claim 5 , wherein the common electrode includes an opaque metallic material.
7 . The display device of claim 1 , further comprising a light shielding film provided on lateral surfaces of the plurality of partition walls.
8 . The display device of claim 1 , wherein, in the plurality of opening areas, the upper surface of the first semiconductor layer has a light extraction pattern.
9 . The display device of claim 1 , further comprising a plurality of reflection electrodes respectively electrically connected to the second semiconductor layer of each of the plurality of light emitting elements.
10 . The display device of claim 1 , wherein the first semiconductor layer is doped with a dopant having a first conductivity type, and the second semiconductor layer of each of the plurality of light emitting elements is doped with a dopant having a second conductivity type which is electrically opposite to the first conductivity type.
11 . The display device of claim 1 , wherein a distance between two adjacent partition walls of the plurality of partition walls is greater than a width of the active layer of each of the plurality of light emitting elements.
12 . The display device of claim 1 , wherein a width of the active layer of each of the plurality of light emitting elements is between 0.1 μm and 100 μm.
13 . The display device of claim 1 , wherein a sum of a height of the first color conversion layer of each of the plurality of color conversion layers and a height of the second color conversion layer of each of the plurality of color conversion layers is less than a height of each of the plurality of partition walls.
14 . The display device of claim 1 , wherein each of the first color conversion layer of each of the plurality of color conversion layers and the second color conversion layer of each of the plurality of color conversion layers includes a photoresist and quantum dots or phosphors dispersed in the photoresist.
15 . The display device of claim 1 , further comprising a plurality of color filters respectively provided on the plurality of color conversion layers.
16 . The display device of claim 15 , further comprising an insulating layer covering each of the plurality of color filters and having a light penetrability with respect to light emitted from the plurality of color conversion layers.
17 . The display device of claim 1 , further comprising a switching circuit configured to simultaneously operate at least a portion of active layers of the plurality of light emitting elements.
18 . The display device of claim 1 , wherein the active layer emits blue light and the blue light passing through the first color conversion layer and the second color conversion layer is changed to white light.
19 . An augmented reality device comprising: a projection system including a display configured to generate an image; and an optical system configured to guide the image generated from the projection system to eyes of a user, wherein the display includes: a plurality of light emitting elements including a first semiconductor layer, each of the plurality of light emitting elements including a second semiconductor layer provided under the first semiconductor layer and an active layer between the first semiconductor layer and the second semiconductor layer; a plurality of partition walls extending from the first semiconductor layer; and a plurality of color conversion layers provided on the plurality of light emitting elements in correspondence with the plurality of light emitting elements and spaced apart from each other by the plurality of partition walls, each of the plurality of color conversion layers including a first color conversion layer and a second color conversion layer stacked on the first color conversion layer, wherein the first semiconductor layer includes an upper surface, a lower surface opposite to the upper surface, the plurality of partition walls protruding and extending from the upper surface, and a plurality of opening areas provided between the plurality of partition walls, and wherein a material of the plurality of partition walls is the same as a material of the first semiconductor layer, and the plurality of partition walls extend in an integrated manner from the upper surface of the first semiconductor layer.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application is based on and claims priority under 35 U.S.C. § 119 to Korean Patent Application Nos. 10-2022-0003567, filed on Jan. 10, 2022, and 10-2022-0061031, filed on May 18, 2022, in the Korean Intellectual Property Office, the disclosure of which is incorporated by reference herein in its entirety. BACKGROUND 1. Field The present disclosure relates to display devices, augmented reality devices including the display devices, and methods of manufacturing the display devices, and more particularly, to high resolution display devices using a micro-light emitting diode (LED), augmented reality devices including the display devices, and methods of manufacturing the display devices. 2. Description of the Related Art A flat panel display such as a liquid crystal display (LCD) or an organic light emitting diode display (OLED) have been widely used as a display device. Light emitting diodes (LED) included in various types of display devices have advantages of low power consumption and environment friendliness. Accordingly, industrial demand for LEDs have been increased. Recently, technologies of fabricating high resolution display devices by using a micro-LED have been expanding remarkably. However, fabrication of high-resolution display devices by using a micro-LED requires high efficiency micro-LED chips. Moreover, a high-level transfer technology is essential to properly arrange the micro-LED chips. A pick and place method is known as a method of transferring the micro-LED chips. SUMMARY Example embodiments provide methods of manufacturing a display device having an improved process yield. Example embodiments also provide a method of manufacturing a display device by patterning a color conversion layer without using a mask, thereby reducing production expenses. Example embodiments also provide methods of manufacturing a display device capable of simplifying designs of a scan driver and a data driver, which are used for control of operations of a plurality of active layers by employing a method of simultaneously driving the plurality of active layers in the process of patterning the color conversion layer without using a mask. Example embodiments also provide methods of manufacturing a display device which minimizes residues left after the patterning of the color conversion layer. Example embodiments also provide high resolution display devices using a micro-LED. Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure. According to an aspect of an example embodiment, a display device includes: a plurality of light emitting elements including a first semiconductor layer, each of the plurality of light emitting elements including a second semiconductor layer provided under the first semiconductor layer and an active layer between the first semiconductor layer and the second semiconductor layer; a plurality of partition walls extending from the first semiconductor layer; and a plurality of color conversion layers provided on the plurality of light emitting elements in correspondence with the plurality of light emitting elements and spaced apart from each other by the plurality of partition walls, each of the plurality of color conversion layers including a first color conversion layer and a second color conversion layer stacked on the first color conversion layer. The first semiconductor layer may include an upper surface, a lower surface opposite to the upper surface, the plurality of partition walls protruding and extending from the upper surface, and a plurality of opening areas provided between the plurality of partition walls. The active layer of each of the plurality of light emitting elements faces a corresponding opening area of the plurality of opening areas on the lower surface of the first semiconductor layer, and in each of the plurality of light emitting elements, the second semiconductor layer is provided under the active layer. The display device may further include a plurality of separation films respectively provided between active layers of adjacent light emitting elements of the plurality of light emitting elements and between second semiconductor layers of the adjacent light emitting elements. The first color conversion layer of each of the plurality of color conversion layers may be provided in a corresponding opening area of the plurality of opening areas on the upper surface of the first semiconductor layer, and the second color conversion layer of each of the plurality of color conversion layers is provided on the corresponding first color conversion layer and may include a material different from that of the first color conversion layer. A material of the plurality of partition walls may be the same as a material of the first semiconductor layer, and the plurality of partition walls may extend i