Nitride Semiconductor Enters Micro-LED Display Market

In early November, Japan-based UV LED manufacturer, Nitride Semiconductors, set-up a 100% owned subsidiary, Micro Nitride, to develop and manufacture micro UV-LED chips for micro-LED displays.outdoor advertising product

Initially targeting flexible displays for next generation smartphones, Nitride Semiconductors is ploughing 100 million yen - nearly £700,000 - into its new venture and expects displays to reach commercial markets come 2020.

"LED prices are coming down and down, and Chinese companies are getting bigger and bigger," says Nitride Semiconductors president and chief executive, Yoshihiko Muramoto. "Japanese LED makers are now in a difficult situation and need to add value, we need to make displays and not just LEDs, so we have established our new company."

Nitride Semiconductors unveiled its first UV LED in 2000 and has since delivered myriad wafers, chips and modules, to UV LED markets worldwide. Its new subsidiary will now produce micro UV-LED chips that comprise the micro UV-LED and a red, green, blue (RGB) phosphor to generate 'natural' white light.

Importantly, Muramoto reckons this UV-LED and RGB phosphor approach eases chip manufacture and leads to better-performing displays than existing methods. Today's fledgling micro-LED displays have typically been manufactured with red, blue and green LEDs or a blue LED that excites red and green phosphors.

However, many issues have stymied development. Take the RGB microLED array; mounting different semiconductor structures at high density isn't easy. What's more, current, voltage and response speeds vary from LED to LED, complicating chip control.

Meanwhile, for the micro blue LED excitation method, only the blue light is directly emitted while the red and green light result from phosphor conversion with an associated time lag. "Synchronising the colour response can be very complicated and we just don't have to manage any time lag," says Muramoto. "Our micro UV LEDs are also easy to mount and we have a fifty year history of using phosphor; it is very natural for us to used UV LEDs for displays and lighting."

The new subsidiary will focus on technology development, rather than manufacturing. As Muramoto puts it: "Japanese companies should aim to develop strong technologies and patents... there are many big LED manufacturers around the world and we can outsource our technology to them."

And with the technology in tow, the chief executive says his company's micro UV-LEDs are ready for mass manufacture, claiming fabrication is 'not so difficult'. Importantly, his company is also working with Japan-based display supplier, V Technology, on display manufacture.