US-12622110-B2 - High pixel density structures and methods of making

Abstract

Methods of making high-pixel-density LED structures are described. The methods may include forming a backplane substrate and a LED substrate. The backplane substrate and the LED substrate may be bonded together, and the bonded substrates may include an array of LED pixels. Each of the LED pixels may include a group of isolated subpixels. A quantum dot layer may be formed on at least one of the isolated subpixels in each of the LED pixels. The methods may further include repairing at least one defective LED pixel by forming a replacement quantum dot layer on a quantum-dot-layer-free subpixel in the defective LED pixel. The methods may also include forming a UV barrier layer on the array of LED pixels after the repairing of the at least one defective LED pixel.

Inventors

• Lisong Xu
• Mingwei Zhu
• Byung Sung Kwak
• Hyunsung BANG
• Liang Zhao
• Hou T. NG
• Sivapackia Ganapathiappan
• Nag Patibandla

Assignees

• APPLIED MATERIALS, INC.

Dates

Publication Date

20260505

Application Date

20240115

Claims (15)

1. 1 . A display, comprising: a first pixel, the first pixel comprising a first set of four subpixels, each subpixel of the first set of four subpixels having a light-emitting diode (LED) between adjacent isolation structures, wherein the adjacent isolation structures define subpixel wells with each well including a respective LED, three of the subpixels of the first set of four subpixels include quantum dot materials that fill the respective subpixel wells and that are configured to emit different colors, and a fourth subpixel of the first set of four subpixels includes a quantum-dot-free matrix material filling the respective subpixel well; and a second pixel, the second pixel comprising a second set of four subpixels, each subpixel of the second set of four subpixels having an LED between adjacent isolation structures, wherein the adjacent isolation structures define subpixel wells with each well including a respective LED, three of the subpixels of the second set of four subpixels include quantum dot materials that fill the respective subpixel wells and that are configured to emit different colors, and a fourth subpixel of the second set of four subpixels includes a quantum dot material that fills the respective subpixel well and that is configured to emit a same green or red color as the quantum dot material of one of the three subpixels of the second set of four subpixels.
2. 2 . The display of claim 1 , wherein each LED comprises a gallium-and-nitrogen-containing light-emitting-diode structure operable to emit a first-wavelength light characterized by a wavelength less than or about 400 nm.
3. 3 . The display of claim 2 , wherein the quantum dot material is operable to absorb a first-wavelength light emitted from the LEDs and emit a second-wavelength light characterized by a longer wavelength than the first-wavelength light.
4. 4 . The display of claim 1 , wherein the fourth subpixel of the first set of four subpixels comprises a UV barrier layer over the quantum-dot-free matrix material.
5. 5 . The display of claim 1 , wherein the display comprises an array of pixels comprising the first pixel, the second pixel, and a plurality of additional pixels.
6. 6 . The display of claim 5 , wherein the array of pixels has a pixel density of greater than or about 1000 pixels per inch.
7. 7 . The display of claim 1 , further comprising a microlens on at least one of the subpixels in each of the first pixel and the second pixel.
8. 8 . The display of claim 1 , further comprising: a backplane layer; an array of pixels in contact with the backplane layer, wherein the array of pixels comprises the first pixel and the second pixel; and a UV barrier layer on the array of pixels, wherein the UV barrier layer covers the quantum dot materials and the quantum-dot-free matrix material.
9. 9 . The display of claim 8 , wherein at least one of the subpixels further comprises a microlens in contact with the UV barrier layer.
10. 10 . The display of claim 8 , wherein the backplane layer comprises a silicon-containing layer with CMOS devices in electrical contact with each of the subpixels in each of the LED pixels.
11. 11 . The display of claim 1 , wherein the display is incorporated into a LED display for a virtual reality headset or augmented reality glasses.
12. 12 . The display of claim 1 , wherein each subpixel has a respective microlens disposed thereover.
13. 13 . The display of claim 1 , wherein a longest dimension of each of the subpixels is less than or about 10 μm.
14. 14 . The display of claim 1 , wherein the isolation structures prevent light emitted from one of the subpixels from being absorbed by an adjacent subpixel.
15. 15 . The display of claim 1 , wherein each subpixel comprises a gallium-and-nitrogen-containing light-emitting diode structure.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 17/345,970 filed Jun. 11, 2021 entitled “HIGH PIXEL DENSITY STRUCTURES AND METHODS OF MAKING,” the entire disclosure of which is hereby incorporated by reference, for all purposes, as if fully set forth herein. TECHNICAL FIELD The present technology relates to semiconductor processes and products. More specifically, the present technology relates to producing semiconductor structures and the devices formed. BACKGROUND Light-emitting-diode (LED) display devices made from millions of micron-sized pixels are made possible by fabrication processes that produce intricately patterned material layers on substrate surfaces. Producing patterned material on a substrate requires controlled methods for deposition and removal of materials. However, with new device designs, producing high-quality layers of material with very precise dimensions may be challenging. Thus, there is a need for improved systems and methods that can be used to produce high-quality materials and structures for LED display devices. These and other needs are addressed by the present technology. SUMMARY The present technology includes exemplary semiconductor processing methods that include forming a backplane substrate and a LED substrate. The backplane substrate and the LED substrate are bonded together, and the bonded substrates include an array of LED pixels. Each of the LED pixels may include a group of isolated subpixels. A quantum dot layer may be formed on at least one of the isolated subpixels in each of the LED pixels. The methods may further include repairing at least one defective LED pixel by forming a replacement quantum dot layer on a quantum-dot-layer-free subpixel in the defective LED pixel. The methods may also include forming a UV barrier layer on the array of LED pixels after the repairing of the at least one defective LED pixel. In additional embodiments, each of the LED subpixels may include a gallium-and-nitrogen-containing light-emitting-diode structure operable to emit a first-wavelength light characterized by a wavelength less than or about 400 nm. In further embodiments, the quantum dot layer is operable to absorb the first wavelength light emitted from the gallium-and-nitrogen-containing light-emitting-diode structure and emit a second-wavelength light characterized by a longer wavelength than the first-wavelength light. In still further embodiments, the replacement quantum dot layer is operable to emit light at the same wavelength as a quantum dot layer formed on a non-operating subpixel in the defective LED pixel. In yet additional embodiments, unrepaired LED pixels include a quantum-dot-layer-free subpixel after the formation of the UV barrier layer on the array of LED pixels. In more embodiments, the array of LED pixels has a pixel density of greater than or about 1000 pixels per inch. In still more embodiments, a longest dimension of each of the isolated subpixels is less than or about 10 μm. In yet more embodiments, the methods further include forming a microlens on at least one of the subpixels in each of the LED pixels. The present technology also includes additional semiconductor processing methods that may include forming a backplane substrate and a LED substrate. The backplane substrate and the LED substrate may be bonded together, and the bonded substrates include an array of LED pixels. Each of the LED pixels may include at least four isolated subpixels. Quantum dot layers may be formed on at least three of the isolated subpixels in each of the LED pixels. Each of the quantum dot layers may be operable to emit visible light at a different wavelength than the other quantum dot layers in the LED pixel. The methods may further include forming a UV barrier layer on the array of LED pixels. In embodiments, at least a portion of the LED pixels includes at least one quantum-dot-layer-free subpixel after the formation of the UV barrier layer. In additional embodiments, a pixel isolation structure may be formed in the LED substrate before the LED substrate and backplane substrate are bonded together. In further embodiments, a pixel isolation structure is formed in the bonded substrates after the LED substrate and backplane substrates are bonded together. In still further embodiments, a LED structure is formed into the LED substrate before the LED substrate and the backplane substrate are bonded together. In yet additional embodiments, a LED structure is formed in the bonded substrates after the LED substrate and the backplane substrate are bonded together. In more embodiments, an additional backplane substrate is bonded to the bonded substrates on an exposed surface of the LED substrate. The present technology further includes semiconductor structures that may include a backplane layer, an array of LED pixels in contact with the backplane layer, and an UV barrier layer on the array of LED pixels. Each of the