Virtual and augmented reality: Researchers pioneer process to stack
micro-LEDs

Date:
February 10, 2023
Source:
Georgia Institute of Technology
Summary:
Researchers are using emerging technology to demonstrate a process
that will enable more immersive and realistic virtual and augmented
reality displays with the world's smallest and thinnest micro-LEDs.


Facebook Twitter Pinterest LinkedIN Email
FULL STORY ==========================================================================
Put on a virtual reality headset and, chances are, it will look like
you are viewing the world through a screen door. Current flat panel
displays use pixels that are visible to the naked eye, along with small
bits of unlit dark space between each pixel that can appear as a black, mesh-like grid.


==========================================================================
Now, researchers from the Georgia Institute of Technology, in
collaboration with researchers from the Massachusetts Institute of
Technology (MIT), have developed a new process based on 2D materials
to create LED displays with smaller and thinner pixels. Enabled by two-dimensional, materials-based layer transfer technology, the innovation promises a future of clearer and more realistic LED displays.

The team published a paper in the journal Naturein February titled,
"Vertical full-colour micro-LEDs via 2D materials-based layer
transfer." Co-authors also include researchers from Sejong University
in Korea, and from additional institutions in the U.S. and South Korea.

Georgia Tech-Europe Professor Abdallah Ougazzaden and research scientist
Suresh Sundaram (who both also hold appointments in Georgia Tech's School
of Electrical and Computer Engineering) collaborated with researchers
from MIT to turn the conventional LED manufacturing process on its head
-- literally.

Instead of using prevailing processes based on laying red, green,
and blue (RGB) LEDs side by side, which limits pixel density, the team vertically stacked freestanding, ultrathin RGB LED membranes, achieving
an array density of 5,100 pixels per inch -- the smallest pixel size
reported to date (4 microns) and the smallest-ever stack height -- all
while delivering a full commercial range of colors. This ultra-small
vertical stack was achieved via the technology of van der Waals epitaxy
on 2D boron nitride developed at the Georgia Tech-Europe lab and the
technology of remote epitaxy on graphene developed at MIT.

The study showed that the world's thinnest and smallest pixeled
displays can be enabled by an active layer separation technology using
2D materials such as graphene and boron to enable high array density
micro-LEDs resulting in full- color realization of micro-LED displays.

One unique facet of the two-dimensional, material-based layer transfer
(2DLT) technique is that it allows the reuse of epitaxial wafers. Reusing
this costly substrate could significantly lower the cost for manufacturing smaller, thinner, and more realistic displays.

"We have now demonstrated that this advanced 2D, materials-based growth
and transfer technology can surpass conventional growth and transfer
technology in specific domains, such as in virtual and augmented reality displays," said Ougazzaden, the lead researcher for the Georgia Tech team.

These advanced techniques were developed in metalorganic chemical vapor deposition (MOCVD) reactors, the key tool for LED production at the wafer scale. The 2DLT technique can be replicated on an industrial scale with
high throughput yield. The technology has the potential to bring the
field of virtual and augmented reality to the next level, enabling the
next generation of immersive, realistic micro-LED displays.

"This emerging technology has a tremendous potential for flexible
electronics and the heterogenous integration in opto-electronics, which
we believe will develop new functionalities and attract industry to
develop commercial products from smartphone screens to medical devices," Ougazzaden said.

* RELATED_TOPICS
o Matter_&_Energy
# Materials_Science # Engineering #
Engineering_and_Construction # Graphene
o Computers_&_Math
# Virtual_Reality # Spintronics_Research #
Mobile_Computing # Computer_Science
* RELATED_TERMS
o Virtual_reality o Grid_computing o Emerging_technologies
o Information_and_communication_technologies o
Quantum_entanglement o Massively_multiplayer_online_game o
Mechanics o Computing_power_everywhere

========================================================================== Story Source: Materials provided by Georgia_Institute_of_Technology. Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Jiho Shin, Hyunseok Kim, Suresh Sundaram, Junseok Jeong, Bo-In Park,
Celesta S. Chang, Joonghoon Choi, Taemin Kim, Mayuran
Saravanapavanantham, Kuangye Lu, Sungkyu Kim, Jun Min Suh, Ki Seok
Kim, Min-Kyu Song, Yunpeng Liu, Kuan Qiao, Jae Hwan Kim, Yeongin
Kim, Ji-Hoon Kang, Jekyung Kim, Doeon Lee, Jaeyong Lee, Justin
S. Kim, Han Eol Lee, Hanwool Yeon, Hyun S. Kum, Sang-Hoon Bae,
Vladimir Bulovic, Ki Jun Yu, Kyusang Lee, Kwanghun Chung, Young
Joon Hong, Abdallah Ougazzaden, Jeehwan Kim. Vertical full-colour
micro-LEDs via 2D materials-based layer transfer. Nature, 2023;
614 (7946): 81 DOI: 10.1038/s41586-022-05612-1 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2023/02/230210145828.htm

--- up 49 weeks, 4 days, 10 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)