INGAAS-GAAS QUANTUM-WELL VERTICAL-CAVITY SURFACE-EMITTING LASER USING MOLECULAR-BEAM EPITAXIAL REGROWTH

Data are presented demonstrating a design and fabrication process for the realization of high-efficiency, low-threshold vertical-cavity InGaAs-GaAs quantum well lasers with light emission through the top (epitaxial) surface. Crystal growth is performed using a two-step molecular beam epitaxial growth process to utilize lateral current injection into the device active region. The device structure allows the top surface (emission side) reflector to be optimized (for either high efficiency or low threshold) after crystal growth through the deposition of electron beam evaporated dielectric layers. Maximum continuous-wave output power in excess of 1.2 mW at 300 K, and differential quantum efficiency greater than 25% (3.9 mA threshold) are demonstrated. Low-threshold values of 2.3 mA are measured on devices with increased mirror reflectivity (through the addition of dielectric layers).