Elusive Green LED Demonstrated

RoseStreet Labs (RSL) has demonstrated a long-wavelength LED device with low-cost silicon wafer substrates that could improve solid-state lighting, LED backlighting and next-generation display technology.

Green and longer-wavelength LEDs have been sought for an extensive period to fill a high-value gap in the rapidly growing global LED market for lighting and illumination, where energy efficiency, cost and miniaturization are critical product characteristics.

RoseStreet Labs' green and longer-wavelength LED using thin-film InGaN-on-silicon technology. (Image: RoseStreet Labs)

RSL said the device complements its proprietary thin-film InGaN-on-silicon technology for high-efficiency photovoltaic applications and power devices. These longer-wavelength devices are fabricated using commercial-scale deposition tools at the company's Nitride Research Center. Silicon substrates have a substantial cost advantage over the more traditional sapphire or silicon carbide substrates typically used in LED fabrication.

Green or longer-wavelength nitride-based LEDs are very challenging to fabricate compared with UV and Blue LEDs because of decreasing quantum efficiencies and have remained a tough milestone for the LED industry.

RSL said it will package the green and longer-wavelength LEDs through its sister company, FlipChip International, adding that the technology could be commercialized in two to three years, with migration to 200-mm silicon substrates. RSL scientists also say they have demonstrated initial tunability of this technology to multicolor and white light spectrums.

For more information, visit: www.rosestreetlabs.com