The world's first long-wavelength LED devices using low-cost silicon wafer substrates were demonstrated by RoseStreet Labs. The company says its technology will find a home in the rapidly growing global LED lighting market where energy efficiency, low cost, and miniaturization are critical product characteristics. The technology, which enables green and longer-wavelength LEDs out to 575 nm, is a significant milestone considering that such longer-wavelength nitride-based LEDs have, until now, been challenging to fabricate compared to blue and ultraviolet (UV) LEDs due to decreasing quantum efficiencies.

The RoseStreet Labs (RSL) LEDs are based on the company's proprietary thin-film indium gallium nitride (InGaN) on silicon technology already used for high-efficiency photovoltaic (PV) applications and power devices. The LED devices are fabricated utilizing commercial-scale deposition tools at RSL's Nitride Research Center in Phoenix, AZ; the silicon substrates have a substantial cost advantage over the more traditional sapphire or silicon-carbide substrates typically used in LED fabrication.

RSL plans to eventually package the green and longer-waverlength LEDs through its sister company, FlipChip International . FCI has extensive experience in packaging semiconductor power devices.

RSL scientists have also demonstrated initial tunability of this technology to multi-color and white-light spectrums. RSL believes this technology can be commercialized in 2-3 years with migration to 200 mm silicon substrates.

Bob Forcier, CEO of RSL, said, "These longer wavelength and Green LED breakthrough devices fit perfectly into RSL's roadmap for disruptive energy innovation at all levels on a global scale and leverages its GaN and InGaN on Silicon investments."