CN-121985635-A - MicroLED display device based on epitaxial reconstruction and preparation method thereof

Abstract

The invention discloses a MicroLED display device based on epitaxial reconstruction and a preparation method thereof, wherein the device comprises a plurality of groups of display units, an N-GaN layer, a selective light source layer, a SiN insulating layer, a P-GaN layer, a first N-type sub-electrode, a first P-type sub-electrode, a bonding layer, a CMOS driver, a bonding layer and a CMOS driver, wherein the N-GaN layer covers part of the upper surface of the N-GaN layer, the SiN insulating layer covers part of the N-GaN layer, the SiN insulating layer covers other part of the upper surface of the N-GaN layer and is positioned at two sides of the selective light source layer, the P-GaN layer covers the selective light source layer, the first N-type sub-electrode is positioned in the N-GaN layer and extends back to the N-GaN layer, the CMOS driver covers the upper surface of the bonding layer and is electrically connected with the N-type sub-electrode and the P-type sub-electrode.

Inventors

• FAN QIAN
• NI XIANFENG
• NAN QI

Assignees

• 苏州汉骅半导体有限公司

Dates

Publication Date

20260505

Application Date

20251231

Claims (10)

1. 1. A method for manufacturing a MicroLED display device based on epitaxial reconstruction, comprising the steps of: Forming a first part comprising the steps of: step 11, providing a silicon substrate, and sequentially epitaxially growing a nucleation layer, a buffer layer and an N-GaN layer on the upper surface of the silicon substrate; step 12, growing a SiN insulating layer on the N-GaN layer through chemical vapor deposition; Step 13, etching a part of the SiN insulating layer to the upper surface of the N-GaN layer to form a groove; Step 14, epitaxially growing a selective light source layer, wherein the selective light source layer fills the grooves, and the length and the width of the selective light source layer parallel to the upper surface of the substrate are smaller than 10 mu m; step 15, flattening the upper surfaces of the SiN insulating layer and the selective light source layer, and epitaxially growing a P-GaN layer; Step 161, etching a part of each layer on the N-GaN layer and a part of the N-GaN layer along the thickness direction of the first component to form a first N-type sub-electrode groove, wherein the first N-type sub-electrode groove penetrates through the SiN insulating layer; Step 162, etching a part of the P-GaN layer along the thickness direction of the first component to form a first P-type sub-electrode groove; Step 17, a first N-type sub-electrode is arranged and positioned in the first N-type sub-electrode groove, and a first P-type sub-electrode is arranged and positioned in the first P-type sub-electrode groove; forming a second part comprising the steps of: step 21, providing a CMOS driver, forming a bonding layer above the CMOS driver; step 22, etching the bonding layer along the thickness direction of the second component to form a first through hole and a second through hole penetrating through the bonding layer; Step 23, setting a second N-type sub-electrode and being positioned in the first through hole, and setting a second P-type sub-electrode and being positioned in the second through hole; Bonding the first component and the second component, comprising the steps of: Step 31, transpose the second component, align and bond the first N-type sub-electrode and the second N-type sub-electrode, and the first P-type sub-electrode and the second P-type sub-electrode, and form an N electrode and a P electrode respectively; And step 32, removing the silicon substrate, the nucleation layer and the buffer layer to obtain the MicroLED display device.
2. 2. The method of manufacturing a MicroLED display device according to claim 1, wherein the steps 12-14 are performed a plurality of times according to parameter settings to form the selective light source layer in a target shape that is a regular trapezoid, an inverted trapezoid, a diamond, a hexagon, or a quadrangle in a direction parallel to the thickness direction of the substrate.
3. 3. The method of claim 1, wherein the step 13 further comprises growing a passivation layer on sidewalls of the recess.
4. 4. A MicroLED display device based on epitaxial reconstruction, comprising a plurality of groups of display cells, the display cells comprising: An N-GaN layer; A selective light source layer covering a portion of an upper surface of the N-GaN layer, the selective light source layer having a length and a width in a plane perpendicular to a thickness of the display unit of less than 10 μm; The SiN insulating layer covers the upper surfaces of other parts of the N-GaN layer and is positioned on the periphery of the selective light source layer; The P-GaN layer covers the upper surfaces of the selective light source layer and the SiN insulating layer; the first N-type sub-electrode is connected in the N-GaN layer, extends back to the N-GaN layer along the thickness direction of the display unit and penetrates through the SiN insulating layer and the P-GaN layer; The first P-type sub-electrode is connected in the P-GaN layer and extends back to the P-GaN layer along the thickness direction of the display unit; The first insulating layer and the second insulating layer respectively cover the side walls of the first N-type sub-electrode and the first P-type sub-electrode; the upper surfaces of the first N-type sub-electrode, the first P-type sub-electrode and the P-GaN layer are positioned on the same datum plane; The bonding layer covers the P-GaN layer and is provided with a first through hole and a second through hole which extend along the thickness direction and are spaced, a second N-type sub-electrode is placed in the first through hole, the second N-type sub-electrode and the first N-type sub-electrode form an N electrode, a second P-type sub-electrode is placed in the second through hole, and the second P-type sub-electrode and the first P-type sub-electrode form a P electrode; And the CMOS driver covers the upper surface of the bonding layer and is electrically connected with the N electrode and the P electrode.
5. 5. The MicroLED display device of claim 4, wherein the selective light source layer has a length and width in a plane perpendicular to the thickness of the display unit of 0.1 μm to 2.5 μm.
6. 6. The MicroLED display device according to claim 4, wherein a cross-sectional shape of the selective light source layer in a thickness direction of the display unit is an inverted trapezoid, a regular trapezoid, a diamond, a hexagon, or a quadrangle.
7. 7. The MicroLED display device of claim 4, wherein the selective light source layer sidewalls are covered with a passivation layer.
8. 8. The display device of claim MicroLED, wherein a projection of the selective light source layer onto the P-GaN layer is located between the first N-type sub-electrode and the first P-type sub-electrode.
9. 9. The MicroLED display device according to claim 4, wherein the N-GaN layer thickness is 1.5 μm-10 μm.
10. 10. The MicroLED display device according to claim 4, wherein the P-GaN layer thickness is 200nm-2 μm.

Description

MicroLED display device based on epitaxial reconstruction and preparation method thereof Technical Field The invention relates to the technical field of semiconductors, in particular to a MicroLED display device based on epitaxial reconstruction and a preparation method thereof. Background Gallium nitride is a semiconductor material with excellent electrical properties and thermal stability, and is very suitable for manufacturing MicroLED with high brightness and high efficiency. The gallium nitride MicroLED has higher luminous efficiency, can obviously reduce energy consumption, and simultaneously provides enough high brightness to meet the requirements of single-color and full-color display. Gallium nitride MicroLED has high stability, can stably operate for a long time without failure, and is particularly important for display devices requiring long-time operation. MicroLED shows that the technology industrialization process is subject to the bottleneck of "mass transfer", which has seen great challenges in terms of efficiency, yield, cost and pixel miniaturization. For example, tens of millions or even hundreds of millions of micron-sized LED chips need to be accurately picked, placed and bonded to a driving backboard, the process is extremely complex, the speed is low, the yield is difficult to improve, and the method is a main cause of high cost. After transfer, the N-type and P-type electrodes and the driving circuit are required to be simultaneously bonded in a miniaturized and high-precision mode for each MicroLED pixels, and the requirements on alignment precision and process stability are extremely high. As pixel sizes shrink (< 10 μm), pick and place difficulties of conventional transfer techniques increase exponentially, limiting further improvements in display resolution and PPI. Or one-time epitaxial growth of all the structures, and then etching and mounting the electrodes, on one hand, the design space of the chip is limited, and the size of the chip cannot be small. The industry is pressing to achieve tighter, more efficient integration of MicroLED with high-performance silicon-based drive circuits. Disclosure of Invention The invention aims to overcome the defects of the prior art, and aims to provide a preparation method of a MicroLED display device based on epitaxial reconstruction, and another aim of the invention is to provide a MicroLED display device based on epitaxial reconstruction. In order to solve the technical problems, the invention provides a preparation method of MicroLED display devices based on epitaxial reconstruction, which comprises the following steps: Forming a first part comprising the steps of: step 11, providing a silicon substrate, and sequentially epitaxially growing a nucleation layer, a buffer layer and an N-GaN layer on the upper surface of the silicon substrate; step 12, growing a SiN insulating layer on the N-GaN layer through chemical vapor deposition; Step 13, etching a part of the SiN insulating layer to the upper surface of the N-GaN layer to form a groove; Step 14, epitaxially growing a selective light source layer, wherein the selective light source layer fills the grooves, and the length and the width of the selective light source layer parallel to the upper surface of the substrate are smaller than 10 mu m; step 15, flattening the upper surfaces of the SiN insulating layer and the selective light source layer, and epitaxially growing a P-GaN layer; Step 161, etching a part of each layer on the N-GaN layer and a part of the N-GaN layer along the thickness direction of the first component to form a first N-type sub-electrode groove, wherein the first N-type sub-electrode groove penetrates through the SiN insulating layer; Step 162, etching a part of the P-GaN layer along the thickness direction of the first component to form a first P-type sub-electrode groove; Step 17, a first N-type sub-electrode is arranged and positioned in the first N-type sub-electrode groove, and a first P-type sub-electrode is arranged and positioned in the first P-type sub-electrode groove; forming a second part comprising the steps of: step 21, providing a CMOS driver, forming a bonding layer above the CMOS driver; step 22, etching the bonding layer along the thickness direction of the second component to form a first through hole and a second through hole penetrating through the bonding layer; Step 23, setting a second N-type sub-electrode and being positioned in the first through hole, and setting a second P-type sub-electrode and being positioned in the second through hole; Bonding the first component and the second component, comprising the steps of: Step 31, transpose the second component, align and bond the first N-type sub-electrode and the second N-type sub-electrode, and the first P-type sub-electrode and the second P-type sub-electrode, and form an N electrode and a P electrode respectively; And step 32, removing the silicon substrate, the nucleation layer and the