Influence of heat treatment on characteristics of injection lasers

An experimental investigation was made of the influence of heat treatment of p–n junctions on the characteristics of epitaxial and diffused GaAs laser diodes. The laser threshold decreased after heat treatment because of increase of the gain factor and the reduction by a factor of 5–10 of the threshold current density. The output power increased because the internal quantum efficiency became greater. The internal optical losses increased severalfold, indicating some deterioration of the waveguide properties.