CN-114072914-B - Method for manufacturing image display device and image display device

CN114072914BCN 114072914 BCN114072914 BCN 114072914BCN-114072914-B

Abstract

The method for manufacturing an image display device according to an embodiment includes a step of preparing a second substrate having a semiconductor layer including a light-emitting layer on a first substrate, a step of preparing a third substrate on which a circuit including a circuit element is formed, a step of bonding the semiconductor layer to the third substrate, a step of etching the semiconductor layer to form a light-emitting element, a step of covering the light-emitting element with an insulating member having light transmittance, and a step of forming a wiring layer electrically connecting the light-emitting element and the circuit element. The light emitting element includes a light emitting surface opposite to a surface bonded to the third substrate. The insulating member is provided so as to distribute light emitted from the light emitting element toward the light emitting surface in a direction normal to the light emitting surface and toward the light emitting surface.

Inventors

Qiu Yuanzhao

Assignees

日亚化学工业株式会社
日亚化学工业株式会社

Dates

Publication Date: 20260421
Application Date: 20200630
Priority Date: 20190710

Claims (11)

1. An image display device is provided with: A circuit element; a first wiring layer electrically connected to the circuit element; an insulating film covering the circuit element and the first wiring layer; A second wiring layer provided on the insulating film; a light-emitting element provided on the second wiring layer and including a light-emitting surface facing the surface on the second wiring layer side; an insulating member that covers at least a part of the light-emitting element and has light transmittance; A third wiring layer electrically connected to the light emitting element and disposed on the insulating member, The light emitting element includes a first semiconductor layer of a first conductivity type provided on the second wiring layer, a light emitting layer provided on the first semiconductor layer, and a second semiconductor layer of a second conductivity type different from the first conductivity type provided on the light emitting layer, The insulating member is provided to distribute light emitted from the light emitting element toward a normal direction of the light emitting surface and toward the light emitting surface, An angle formed between a side surface of the light emitting element and a surface of the second wiring layer provided with the light emitting element is smaller than a critical angle in the side surface of the light emitting element determined based on a refractive index of the light emitting element and a refractive index of the insulating member, The critical angle θc0 is obtained by using the following formula (1), θc0 = 90°- sin －1 (n1 / n0) (1) Θc0 is a critical angle, n1 is a refractive index of the insulating member, and n0 is a refractive index of the light emitting element.
2. The image display device according to claim 1, wherein, The insulating member covers a side surface of the light emitting element and includes a part of a spherical surface protruding toward the light emitting surface side.
3. The image display device according to claim 1, wherein, The insulating member has a first height from a first surface of the second wiring layer where the light emitting element is provided, which is higher than a second height from the first surface of the light emitting layer, The second surface is a surface on the side where the second semiconductor layer is provided.
4. The image display device according to claim 3, wherein, The angle is less than 70 °.
5. The image display device according to claim 1, wherein, The second wiring layer includes a wiring portion having light shielding properties, The first semiconductor layer is provided on the wiring portion and is electrically connected to the wiring portion, The outer periphery of the wiring portion includes an outer periphery of the light emitting element projected to the wiring portion.
6. The image display device according to claim 1, wherein, The first conductivity type is a p-type, The second conductivity type is n-type.
7. The image display device according to claim 1, wherein, The insulating member has an opening exposing at least a part of the light emitting surface, and a translucent electrode is provided on an exposed surface exposed from the light emitting surface.
8. The image display device according to any one of claim 1 to 7, wherein, The light emitting element includes a gallium nitride-based compound semiconductor, The circuit element is formed on a substrate, the substrate containing silicon.
9. The image display device according to claim 1, wherein, The light emitting element further includes a wavelength conversion member.
10. An image display device is provided with: A plurality of transistors; a first wiring layer electrically connected to the plurality of transistors; An insulating film covering the plurality of transistors and the first wiring layer; A second wiring layer provided on the insulating film; a first semiconductor layer, which is provided on the second wiring layer and is of a first conductivity type; a light emitting layer disposed on the first semiconductor layer; a second semiconductor layer which is arranged on the light-emitting layer and has a second conductivity type different from the first conductivity type; An insulating member that covers the first semiconductor layer and the light-emitting layer, covers at least a part of the second semiconductor layer, and has light transmittance; A third wiring layer connected to light-transmitting electrodes disposed on a plurality of exposed surfaces of the second semiconductor layer exposed from the insulating member in correspondence with the plurality of transistors, The insulating member is provided so as to distribute light emitted from the light-emitting layer toward the exposed surfaces in a direction normal to the exposed surfaces, respectively, The light emitting element includes a first semiconductor layer of a first conductivity type provided on the second wiring layer, a light emitting layer provided on the first semiconductor layer, and a second semiconductor layer of a second conductivity type different from the first conductivity type provided on the light emitting layer, An angle formed between a side surface of the light emitting element and a surface of the second wiring layer provided with the light emitting element is smaller than a critical angle in the side surface of the light emitting element determined based on a refractive index of the light emitting element and a refractive index of the insulating member, The critical angle θc0 is obtained by using the following formula (1), θc0 = 90°- sin －1 (n1 / n0) (1) Θc0 is a critical angle, n1 is a refractive index of the insulating member, and n0 is a refractive index of the light emitting element.
11. The image display device of claim 10, wherein, The second semiconductor layer is separated by the insulating member.

Description

Method for manufacturing image display device and image display device Technical Field The present invention relates to a method for manufacturing an image display device and an image display device. Background A thin image display device having high brightness, a wide viewing angle, high contrast, and low power consumption is desired. In order to cope with such market demands, development of display devices using self-light emitting elements is underway. As the self-luminous element, a display device using a micro LED as a micro light-emitting element is expected. As a method of manufacturing a display device using micro LEDs, a method of sequentially transferring micro LEDs formed separately to a driving circuit is described. However, as the number of micro LEDs increases with the full definition or high image quality such as 4K and 8K, a transfer process takes a long time when a plurality of micro LEDs are formed and sequentially transferred onto a substrate on which a driving circuit or the like is formed. Further, there is a possibility that connection failure between the micro LED and the driving circuit or the like occurs, and yield is lowered. There is known a technique of growing a semiconductor layer including a light-emitting layer on a Si substrate, forming an electrode on the semiconductor layer, and then adhering the electrode to a circuit substrate on which a driving circuit is formed (for example, patent document 1). Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 2002-141492 Disclosure of Invention An embodiment of the present invention provides a method for manufacturing an image display device and an image display device, which can shorten a transfer process of a light emitting element and improve a yield. A method for manufacturing an image display device according to one embodiment of the present invention includes a step of preparing a second substrate having a semiconductor layer including a light-emitting layer on a first substrate, a step of preparing a third substrate on which a circuit including a circuit element is formed, a step of bonding the semiconductor layer to the third substrate, a step of etching the semiconductor layer to form a light-emitting element, a step of covering the light-emitting element with a light-transmissive insulating member, and a step of forming a wiring layer electrically connecting the light-emitting element and the circuit element. The light emitting element includes a light emitting surface opposite to a surface bonded to the third substrate. The insulating member is provided so as to distribute light emitted from the light emitting element toward the light emitting surface in the normal direction of the light emitting surface and toward the light emitting surface. The image display device according to one embodiment of the present invention includes a circuit element, a first wiring layer electrically connected to the circuit element, an insulating film covering the circuit element and the first wiring layer, a second wiring layer provided on the insulating film, a light-emitting element provided on the second wiring layer and including a light-emitting surface facing the second wiring layer, an insulating member covering at least a part of the light-emitting element and having light transmittance, and a third wiring layer electrically connected to the light-emitting element and disposed on the insulating member. The light emitting element includes a first semiconductor layer of a first conductivity type provided on the second wiring layer, a light emitting layer provided on the first semiconductor layer, and a second semiconductor layer of a second conductivity type different from the first conductivity type provided on the light emitting layer. The insulating member is provided so as to distribute light emitted from the light emitting element toward the light emitting surface in a direction normal to the light emitting surface and toward the light emitting surface. The image display device according to one embodiment of the present invention includes a plurality of transistors, a first wiring layer electrically connected to the plurality of transistors, an insulating film covering the plurality of transistors and the first wiring layer, a second wiring layer provided on the insulating film, a first semiconductor layer provided on the second wiring layer and having a first conductivity type, a light-emitting layer provided on the first semiconductor layer, a second semiconductor layer provided on the light-emitting layer and having a second conductivity type different from the first conductivity type, an insulating member covering the first semiconductor layer and the light-emitting layer and covering at least a part of the second semiconductor layer and having light transmittance, and a third wiring layer connected to light-transmitting electrodes provided on a plurality of exposed surfaces of the second se