CW InGaN multiple-quantum-well laser diodes on copper and diamond substrates by laser lift-off

Continuous-wave (cw) InGaN multiple-quantum-well laser diodes grown on sapphire substrates by metalorganic chemical vapor deposition were successfully transferred onto copper and diamond using excimer laser lift-off. Room-temperature cw threshold currents as low as 87 mA with threshold voltages of 5.8 V were obtained for laser diodes on diamond substrates. GaN-based laser structures transferred onto Cu substrates show a significantly reduced thermal resistance resulting in a more than 2× increase in cw output power of more than 100 mW. High-quality cleaved facet have been obtained for free-standing GaN laser membranes after sapphire substrate removal.