6 February 2017

Leti presents 873x500-resolution, 10μm-pixel-pitch micro-LED displays at Photonics West

On 2 February at SPIE Photonics West 2017 in San Francisco, micro/nanotechnology R&D center CEA-Leti of Grenoble, France presented a micro light-emitting diode (μLED) fabrication process for creating high-resolution arrays at 10μm pitch ('Processing and Characterization of High-Resolution GaN/InGaN LED Arrays at 10-Micron Pitch for Micro-Display Applications'). That pixelization, and the 873 x 500 resolution that are enabled by the new process, exceed state-of-the-art technology, it is claimed.

Designed for micro-display applications such as augmented-reality (AR) or virtual-reality (VR) tools and wearable devices, the blue or green GaN/InGaN µLED arrays use Leti's proprietary self-aligned technology (key to achieving such a small pixel pitch). A combination of several damascene metallization steps used to create a common cathode is also expected to provide good thermal dissipation and prevent voltage drops within the micro-LED matrix. Electro-optical measurements show record efficiency and brightness exceeding requirements for device integration.

"Leti's self-aligned process allows the creation of high-resolution µLED matrices with a reduced pixel pitch of 10µm and paves the way towards even smaller pitches for next-generation devices," says Ludovic Dupré, one of the paper's authors. "In addition, the use of the damascene metallization process of the cathode, which also is a new process developed at Leti, is a breakthrough compared to previous demonstrations of micro-LED matrices. The common cathode indeed fills the whole volume between the micro-LEDs and provides metallic spreading of electrical current between them, as well as thermal dissipation," he adds. "These results are promising for integrating a micro-LED matrix in micro-display devices by hybridization on CMOS active matrices, and first prototypes are currently being tested."

See related items:

Leti demos new process for fabricating high-brightness micro-LED arrays for next-gen head-mounted and head-up displays

Tags: Leti microLED

Visit: http://spie.org/photonics-west.xml

Visit: www.leti.fr