The integration of InxGa1-xN multiple-quantum-well laser diodes with copper substrates by laser lift-off

Indium-gallium nitride (InGaN) multiple-quantum-well ridge-waveguide laser diodes (LDs) grown by metalorganic chemical vapor deposition on sapphire su bstrates were successfully transferred onto Cu substrates using a laser lif t-off (LLO) process. Characterization of the InGaN LDs before and after the sapphire substrate removal revealed no measurable degradation in device pe rformance. The threshold current, under pulsed operation, for a 3 mum ridge -waveguide device and the laser-emission spectrum remained essentially unch anged after the LLO process. In addition, the conductive Cu substrate permi tted realization of LDs with vertical-current injection using the Cu as the backside contact.