GaN-based LEDs and lasers on SiC

At OSRAM Opto Semiconductors GaN based devices are grown using metalorganic vapor phase epitaxy (MOVPE) on SiC substrates. SIC as a substrate offers m any advantages both from epitaxial and device processing point of view. For production on an industrial scale both a stable epitaxial process and a lo w cost chip technology had to be developed. By using an optimized GaInN MQW for the active region and an improved chip technology as well as package d esign leading to a better light extraction the LED optical output at 460 nm exceeds now 7 mW at 20 mA in a 5 mm radial lamp. By optimizing buffer grow th and GaInN active region, p- and n-contacts, grinding and polishing proce sses as well as facet cleaving the first European GaN based violet laser di ode could be realized. The device had an emission wavelength of 420 nm, a t hreshold current density of less than 17 kA/cm(2) at 25 V and operated unde r pulsed current injection at room temperature.