EDN Electronic Technology Design

Porotech, a spin-off from the University of Cambridge, has raised £300,000 for the next phase of development of its unique Micro-LED technology. Its display technology breakthrough heralds a new era of brighter, clearer and more vivid miniature displays for even the smallest devices.

Micro-LED is the next big leap for displays in products such as smartphones, smartwatches and VR / AR headsets. It is particularly useful in outdoor settings, where sunlight often makes it difficult to see on existing displays. But the performance of current Micro-LED technologies deteriorates as device sizes decrease.

Porotech has created a new class of porous gallium nitride (GaN) semiconductor materials that redefine what is possible. It provides performance improvements suitable for volume production and can be customized to meet individual customer needs.

Despite only being established on January 20, Porotech has already generated 10 months of revenue - and is working with some of the world's biggest names in display technology. In November 2020, the company launched the world's first commercial native red indium gallium nitride (InGaN) LED epitaxial wafer for micro-LED applications.

“Micro-LED displays using GaN-based material technology are widely recognized as the only technology capable of providing sufficient brightness and efficiency to meet AR requirements,” Says Dr. Tongtong Zhu, CEO and Co-Founder of Porotech, “With AR glasses expected to one day replace smartphones - or at least reduce our interaction with devices in our pockets - it's vital to develop advanced materials to improve performance. "

“Integrating AlInGaP red and InInGaN green and blue LED displays into modules with micron pixels is extremely challenging, Because of the high surface recombination speed in AlInGaP devices, this material is not suitable for highly efficient Micro-LED. Our breakthrough extends the emission range of InGaN LEDs to meet the performance needs of red displays while providing the ability to extend the wafer sizes required for miniature LED semiconductor display technology.”

Porotech's native red InGaN miniature LEDs have a wavelength of 640 nm at 10A / cm2, And at very small pixels and spacing than conventional AlInGaP and color conversion red has higher performance.

the next step

Porotech will now work to extend its new approach to incorporating InGaN based red, green and blue (RGB) Micro-LED is integrated into full-color miniature displays - and ultimately creates "smart" pixels that can be independently controlled for unparalleled response and accuracy just like AR gestures.

Currently, smart pixel technologies being tested are mainly based on aluminum indium gallium phosphide (AlInGaP) and quantum dot color conversion (QDCC). But AllnGaP struggled with the small pixel size required for AR - and QDCC had uniformity and stability problems. In addition, both methods require mixing different materials.

For more information on technology

Porotech's novel approach enables all three primary colors to be made using the same GaN material and integrated on a single chip without special construction. The company also plans to develop its own supply-chain ecosystem to help it develop and produce products more quickly.

Dr. Tongtong Zhu, CEO and Co-Founder of Porotech, said: “Porous GaN is basically GaN with holes of tens of nanometers. “This is a brand new engineered GaN material platform for building semiconductor devices. It provides performance improvements suitable for mass production, scalable wafer sizes - essential for the next generation of micro-display devices such as AR glasses.

“We have seen high demand for our standard and custom porous GaN substrates and Micro-LED epitaxial wafers, We can offer these on 100mm (4 ") to 300mm (12") sapphire and silicon platforms.

“Smart pixels will be our next direction - monolithic generation and integration of native self-emitting RGB micro-LEDs on a single wafer, To provide smaller, lighter, thinner displays that use less energy and provide the higher accuracy required for AR gestures and the like.”

Porotech's latest funding round was led by Speedinvest, followed by previous investors IQ Capital, Cambridge Enterprise, Martlet and Bridge Angels.

Rick Hao, head of Speedinvest, said: “With growing demand for smaller, lighter, clearer displays that are more accurate and environmentally friendly than ever before, Porotech develops revolutionary technologies that will transform the electronics industry. "This new porous GaN semiconductor material is suitable for existing industrial processes and is robust and flexible enough to be customized for different applications."