Chemically assisted ion beam etching process for high quality laser mirrors

A process for the fabrication of mirror facets for AlGaAs/GaAs laser diodes is described. The major requirements for the fabrication of high quality mirrors have been fulfilled by using Cl 2/Ar chemically assisted ion beam etching (CAIBE) and a new multilayer mask structure that produces the smoothest facets. The fabricated AlGaAs/GaAs SQW-GRIN-SCH lasers with etched mirrors show characteristics similar to those of lasers with cleaved mirrors on the same substrate. Results of on-wafer testing of laser threshold uniformity by means of monitor diodes indicate the potential of the process for laser integration and full wafer fabrication and testing.