KAIST team develops flexible vertical micro LED

A KAIST research team led by Professor Keon Jae Lee from the Department of Materials Science and Engineering and Professor Daesoo Kim from the Department of Biological Sciences has developed flexible vertical micro LEDs (f-VLEDs) using anisotropic conductive film (ACF)-based transfer and interconnection technology.

The team also succeeded in controlling animal behavior via optogenetic stimulation of the f-VLEDs.

Flexible micro LEDs have become a strong candidate for the next-generation display due to their ultra-low power consumption, fast response speed, and excellent flexibility. However, the previous micro LED technology had critical issues such as poor device efficiency, low thermal reliability, and the lack of interconnection technology for high-resolution micro LED displays.

The research team has designed new transfer equipment and fabricated a f-VLED array (50x50) using simultaneous transfer and interconnection through the precise alignment of ACF bonding process. These f-VLEDs achieved optical power density (30 mW/mm2) three times higher than that of lateral micro LEDs, improving thermal reliability and lifetime by reducing heat generation within the thin film LEDs.

These f-VLEDs (thickness: 5 micrometre, size: below 80 micrometre) can be applied to optogenetics for controlling the behavior of neuron cells and brains. In contrast to the electrical stimulation that activates all of the neurons in brain, optogenetics can stimulate specific excitatory or inhibitory neurons within the localized cortical areas of the brain, which facilitates precise analysis, high-resolution mapping, and neuron modulation of animal brains.

In this work, they inserted the innovative f-VLEDs into the narrow space between the skull and the brain surface and succeeded in controlling mouse behavior by illuminating motor neurons on two-dimensional cortical areas located deep below the brain surface.

Professor Lee said, "The flexible vertical micro LED can be used in low-power smart watches, mobile displays, and wearable lighting. In addition, these flexible optoelectronic devices are suitable for biomedical applications such as brain science, phototherapeutic treatment, and contact lens biosensors."

He recently established a startup company ( FRONICS Inc. ) based on micro LED technology and is looking for global partnerships for commercialization. This result entitled "Optogenetic Control of Body Movements via Flexible Vertical Light-Emitting Diodes on Brain Surface " was published in the February 2018 issue of Nano Energy.

Related Links
The Korea Advanced Institute of Science and Technology
Satellite-based Internet technologies

Tweet

Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Monthly Supporter
$5+ Billed Monthly

paypal only

SpaceDaily Contributor
$5 Billed Once

credit card or paypal

Major Xerox investor sues to block takeover by Fujifilm
New York (AFP) Feb 14, 2018
One of Xerox's biggest shareholders filed suit to challenge the US photocopier and printer maker's planned takeover by Japanese technology firm Fujifilm. Darwin Deason who along with Carl Icahn controls 15.2 percent of Xerox shares, filed suit against Xerox and Fujifilm on Tuesday, alleging fraud. Xerox said the allegations are "without merit" and that it will "vigorously defend itself." Under the planned deal, Xerox would be absorbed by an existing joint venture known as Fuji Xerox, falling ... read more