Rectangular and L-shaped GaAs/AlGaAs lasers with very high quality etched facets

GaAs/AlGaAs semiconductor lasers with very high quality etched facets have been fabricated. Laser facets are formed by the chemically assisted ion beam etching technique with SiO2 as the etch mask. The threshold current densities of lasers produced with this technique are almost identical to comparable lasers with one etched and one cleaved facet. L-shaped lasers, which make use of total internal reflection, have also been fabricated. The threshold current density of L-shaped lasers is similar to that of rectangular lasers with comparable cavity length.