The agreement was signed a year ago, and the transfer of the GaN-on-Si process technology is exclusive to Osram Opto Semiconductors until November 7, 2010. Outside the Osram agreement, Azzurro is able to license its technology to other parties, and continues to supply GaN-on-Si epiwafers to other customers.
The proprietary GaN-on-Si technology was developed by Magdeburg, Germany-based Azzurro Semiconductors over the last six years. It enables the growth of thick and crack-free GaN-layers on silicon substrates with an excellent crystal quality and minimum bow, says Azzurro.
Most LED epiwafers are grown using sapphire or silicon carbide substrates as the starting material on which to deposit GaN-based multilayer LED structures. Wafer sizes range from 2 to 4 inches. The use of larger, lower-cost silicon substrates could lead to significant device-cost reductions, provided that high quality device layers can be grown successfully.
Erwin Wolf, CEO of Azzurro Semiconductors said “This license and transfer agreement is a big step for the commercialization of LEDs produced on silicon substrates. Our technology will enable manufacturers to use silicon fabs to produce LEDs on 150 mm, and in future also on 200 mm silicon substrates. We are very glad to work with Osram Opto Semiconductors, since it is a leader in LED technology.”
Having pioneered the growth of GaN on silicon substrates using metalorganic vapour phase epitaxy (MOVPE), Azzurro is currently providing its customers worldwide with GaN-on-Si epiwafers for LED and high-voltage applications.
Azzurro says that its unique capability to grow very thick (8 micron) high-quality GaN on silicon substrates (currently 150 mm) is expected to enable cost breakthroughs for high-brightness LEDs and GaN-based high-voltage devices.