Porotech raises £3m for new generation of microdisplays

2 min read

Porotech, the University of Cambridge spin-out has raised £3m to fund the next stage of development of its innovative micro-LED production technique.

The company's display technology is seen as heralding a new era in terms of brighter, sharper, more vivid microdisplays for even the smallest devices.

Micro-LED is the next major step forward for displays on products such as smartphones, smartwatches and VR/AR headsets and it is particularly useful in outdoor settings, where sunlight can often make existing displays difficult to see clearly. However, the performance of current micro-LED technologies deteriorates as the device size decreases.

In response, Porotech has created a new class of porous gallium nitride (GaN) semiconductor material that offers performance improvements that are suitable for mass production and can be customised for individual customers’ needs.

Despite only spinning out in January 2020, Porotech has been generating revenue for 10 months and is currently working with a number of the biggest global names in display technology. In November last year, the company launched the world's first commercial native red indium gallium nitride (InGaN) LED epiwafer for micro-LED applications.

Porotech said that its next step is to expand its novel approach to integrate InGaN-based red, green and blue (RGB) micro-LEDs for full-colour microdisplays – and ultimately create 'smart' pixels that can be controlled independently for unrivalled responsiveness and accuracy for things like AR gestures.

Currently, technologies being tested for smart pixels are largely based on aluminum indium gallium phosphide (AlInGaP) material and quantum dot colour conversion (QDCC). But AllnGaP struggles at the small pixel sizes required by AR, while QDCC suffers from uniformity and stability issues. In addition, both approaches require a mixture of different material.

By contrast Porotech's approach enables all three primary colours to be made with the same GaN material and integrated on a single wafer, with no need for special structuring. The company also plans to develop its own supply chain ecosystem to help it develop and produce products more quickly.

"Porous GaN is basically GaN with tiny holes in it that are a few tens of nanometres across," said Porotech CEO and co-founder Dr Tongtong Zhu. "It's an entirely new engineered GaN material platform to build semiconductor devices on. It offers performance improvements that are suitable for mass production, scalable in wafer size – and crucial for the next generation of microdisplay devices such as AR glasses.

"We are already seeing high levels of demand for our standard and customised porous GaN substrates and micro-LED epiwafers, which we can provide on sapphire and silicon platforms ranging from 100mm (4") to 300mm (12").

“Smart pixels will be our next development – monolithically generated and integrating native self-emissive RGB micro-LEDs on a single wafer to give smaller, lighter, thinner displays that use less energy and offer the greater accuracy required for things like AR gestures."

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