CN-121985657-A - Micro light emitting diode display device and manufacturing method thereof

CN121985657ACN 121985657 ACN121985657 ACN 121985657ACN-121985657-A

Abstract

The application relates to a micro light emitting diode display device and a manufacturing method thereof, wherein the display structure comprises a first substrate and a plurality of micro light emitting diodes, the micro light emitting diodes are arranged on the first substrate in an array mode, each micro light emitting diode comprises an epitaxial structure positioned on the first substrate and a transparent conductive layer positioned on the epitaxial structure, the driving back plate is positioned on one side, far away from the first substrate, of the micro light emitting diodes, the driving back plate comprises a second substrate and a plurality of driving transistors, the driving transistors are arranged on the second substrate in an array mode, and each micro light emitting diode is aligned with one driving transistor in the direction perpendicular to the surface of the second substrate. The application realizes the accurate control between the driving transistor and the micro light emitting diode, and improves the resolution and the transmittance of the micro light emitting diode display device.

Inventors

PAN ANLIAN
LENG MEIYING
HE KUN

Assignees

湖南师范大学
湖南大学

Dates

Publication Date: 20260505
Application Date: 20251010

Claims (11)

1. A micro light emitting diode display device, comprising: the display structure comprises a first substrate and a plurality of micro light emitting diodes, wherein the micro light emitting diodes are arranged on the first substrate in an array manner, and each micro light emitting diode comprises an epitaxial structure positioned on the first substrate and a transparent conductive layer positioned on the epitaxial structure; The driving backboard is positioned at one side of the micro light emitting diode far away from the first substrate, and comprises a second substrate and a plurality of driving transistors, and the driving transistors are arranged on the second substrate in an array manner; Wherein each micro light emitting diode is aligned with one of the driving transistors in a direction perpendicular to a surface of the second substrate.
2. The micro light emitting diode display device according to claim 1, wherein the driving transistor comprises: the first dielectric layer is positioned on the second substrate; The grid electrodes are arranged on the first dielectric layer in an array manner, and the orthographic projection of the grid electrodes towards the second substrate is at least partially overlapped with the orthographic projection of the micro light emitting diode towards the second substrate; the second dielectric layer covers the first dielectric layer and the grid electrode; the channel region is positioned on the second dielectric layer, and the orthographic projection of the channel region towards the second substrate is at least partially overlapped with the orthographic projection of the grid electrode towards the second substrate; The source electrode is positioned on the second dielectric layer and covers the side wall of one side of the channel region and at most part of the surface of the channel region; And the drain electrode is positioned on the second dielectric layer and covers the side wall of the channel region at the side far away from the source electrode and the most part of the surface of the channel region at the side far away from the source electrode.
3. The micro light emitting diode display device according to claim 2, wherein the micro light emitting diode and the driving transistor aligned with each other are connected by an electrical connection member, and both ends of the electrical connection member are connected to the source electrode and the transparent conductive layer, respectively.
4. The micro light emitting diode display device according to claim 1 or 2, wherein the display structure further comprises: an insulating passivation layer covering the first substrate and all the micro light emitting diodes; The first packaging layer is positioned on the insulating passivation layer, and the driving backboard is positioned on the first packaging layer; The drive back plate further includes: And the second packaging layer at least covers all the driving transistors.
5. The micro light emitting diode display device according to claim 4, wherein the material of the transparent conductive layer comprises at least one of indium tin oxide, aluminum doped zinc oxide, and gallium doped zinc oxide, the material of the first encapsulation layer and the material of the second encapsulation layer each comprise a polyimide material, and the visible light transmittance of the polyimide material ranges from 90% to 100%, and the material of the second substrate comprises sapphire.
6. The micro light emitting diode display device according to claim 1, wherein the first substrate includes a first transparent conductive oxide layer, a thin film metal layer, and a second transparent conductive oxide layer sequentially stacked in a direction away from the transparent conductive layer.
7. A method of manufacturing a micro light emitting diode display device, comprising: providing a substrate, forming an epitaxial structure on the substrate, and forming a transparent conductive layer on the epitaxial structure; Removing the substrate, and forming a first base on one side of the epitaxial structure far away from the transparent conductive layer; Patterning the epitaxial structure and the transparent conductive layer to form a plurality of micro light emitting diodes arranged in an array on the first substrate; And forming a driving backboard on the display structure, wherein the display structure comprises the first substrate and all the micro light emitting diodes, the driving backboard comprises a second substrate formed on the display structure and a plurality of driving transistors formed on the second substrate, and each driving transistor is aligned with one micro light emitting diode along the direction perpendicular to the surface of the second substrate.
8. The method of claim 7, wherein forming the epitaxial structure and the transparent conductive layer on the substrate comprises: forming the epitaxial structure on the substrate by adopting a chemical vapor deposition process; forming the transparent conductive layer on the epitaxial structure by adopting a magnetron sputtering growth process; And carrying out thermal annealing treatment on the transparent conductive layer.
9. The method of claim 7, wherein removing the substrate and forming a first base on a side of the epitaxial structure away from the transparent conductive layer comprises: Removing the substrate by adopting at least one of a wet etching process and a chemical mechanical polishing process; forming the first substrate on one side of the epitaxial structure far away from the transparent conductive layer by adopting an electron beam evaporation process and a magnetron sputtering process; the first substrate comprises a first transparent conductive oxide layer, a thin film metal layer and a second transparent conductive oxide layer which are sequentially formed along a direction away from the transparent conductive layer.
10. The method of manufacturing a micro light emitting diode display device according to claim 7, wherein after patterning the epitaxial structure and the transparent conductive layer, before forming the driving back plate on the display structure, the method further comprises: forming an insulating passivation layer on the first substrate and the micro light emitting diode by adopting a deposition process, wherein the insulating passivation layer covers the side wall of the micro light emitting diode; forming a first packaging layer on the insulating passivation layer, wherein the surface of the first packaging layer is higher than the surface of the micro light emitting diode; flattening the first packaging layer to flatten the surface of the first packaging layer far away from the first substrate; The display structure comprises the first substrate, all the micro light emitting diodes, the insulating passivation layer and the first packaging layer.
11. The method of manufacturing a micro light emitting diode display device according to claim 10, wherein the driving back plate forming process includes: Forming the second substrate on the first packaging layer; forming a first dielectric layer on the second substrate; Forming a grid electrode material layer on the first dielectric layer, and carrying out graphical treatment on the grid electrode material layer to form a plurality of grid electrodes arranged in an array mode, wherein orthographic projection of the grid electrodes towards the second substrate is at least partially overlapped with orthographic projection of the micro light emitting diodes towards the second substrate; forming a second dielectric layer on the first dielectric layer and the grid electrode; forming a plurality of channel regions on the second dielectric layer, and enabling orthographic projection of the channel regions towards the second substrate to be at least partially overlapped with orthographic projection of the grid electrodes towards the second substrate; Etching the second dielectric layer, the first dielectric layer, the second substrate, the first packaging layer and the insulating passivation layer to form a contact hole exposing the transparent conductive layer, and forming an electric connecting piece in the contact hole; Forming a source electrode and a drain electrode on the second dielectric layer, so that the source electrode covers the electric connection piece, the side wall at one side of the channel region and the multi-part surface of the channel region, and the drain electrode covers the side wall at one side of the channel region far away from the source electrode and the multi-part surface at one side of the channel region far away from the source electrode, so as to form the driving transistor; and forming a second packaging layer on the driving transistor.

Description

Micro light emitting diode display device and manufacturing method thereof Technical Field The present application relates to the field of display technologies, and in particular, to a micro light emitting diode display device and a manufacturing method thereof. Background The current mainstream Liquid crystal display (Liquid CRYSTAL DISPLAY, LCD) and Organic LIGHT EMITTING (LED) technologies have problems of limited brightness, high power consumption, short service life, and the like. In contrast, inorganic Micro light emitting diodes (Micro-LEDs) are ideal choices in the field of transparent display by virtue of their high brightness (i.e., brightness up to 10 6 nit), low power consumption (80% reduction in energy consumption), long lifetime, etc. In a general micro light emitting diode transparent display technology, a scheme of bonding a micro light emitting diode with a horizontal structure and a low-temperature polysilicon thin film transistor (Low Temperature Poly-silicon Thin Film Transistor, LTPS-TFT) back plate is generally adopted, so that 60% transmittance is realized. However, the pixel size in this scheme is generally 10 μm, and the opaque region of the driving circuit used is more than 40% of the total region area, and therefore, the transmittance of the above scheme is difficult to further increase, limited by the pixel size and the driving circuit opaque region ratio. Disclosure of Invention Accordingly, it is necessary to provide a micro light emitting diode display device and a method for manufacturing the same to simultaneously improve transmittance and resolution of the micro light emitting diode display device. The application provides a micro light emitting diode display device, comprising: The display structure comprises a first substrate and a plurality of micro light emitting diodes, wherein the micro light emitting diodes are arranged on the first substrate in an array manner, and each micro light emitting diode comprises an epitaxial structure positioned on the first substrate and a transparent conductive layer positioned on the epitaxial structure; The driving backboard is positioned at one side of the micro light emitting diode far away from the first substrate, and comprises a second substrate and a plurality of driving transistors, and the driving transistors are arranged on the second substrate in an array manner; Wherein each micro light emitting diode is aligned with one of the driving transistors in a direction perpendicular to a surface of the second substrate. In one embodiment, the driving transistor includes: the first dielectric layer is positioned on the second substrate; The grid electrodes are arranged on the first dielectric layer in an array manner, and the orthographic projection of the grid electrodes towards the second substrate is at least partially overlapped with the orthographic projection of the micro light emitting diode towards the second substrate; the second dielectric layer covers the first dielectric layer and the grid electrode; the channel region is positioned on the second dielectric layer, and the orthographic projection of the channel region towards the second substrate is at least partially overlapped with the orthographic projection of the grid electrode towards the second substrate; The source electrode is positioned on the second dielectric layer and covers the side wall of one side of the channel region and at most part of the surface of the channel region; And the drain electrode is positioned on the second dielectric layer and covers the side wall of the channel region at the side far away from the source electrode and the most part of the surface of the channel region at the side far away from the source electrode. In one embodiment, the micro light emitting diode and the driving transistor aligned with each other are connected by an electrical connector, and two ends of the electrical connector are respectively connected to the source electrode and the transparent conductive layer. In one embodiment, the display structure further includes: an insulating passivation layer covering the first substrate and all the micro light emitting diodes; The first packaging layer is positioned on the insulating passivation layer, and the driving backboard is positioned on the first packaging layer; The drive back plate further includes: And the second packaging layer at least covers all the driving transistors. In one embodiment, the material of the transparent conductive layer includes at least one of Indium Tin Oxide (ITO), aluminum doped zinc oxide (AZO), and gallium doped zinc oxide (GZO), the materials of the first and second encapsulation layers each include a polyimide material, the visible light transmittance range of the polyimide material includes 90% -100%, and the material of the second substrate includes sapphire. In one embodiment, the first substrate includes a first transparent conductive oxide layer, a thin film metal layer, and a s