Device properties of homo- and heteroepitaxial ZnSe-based laser diodes

The characteristics of ZnSe-based laser diodes grown on GaAs and ZnSe subst rates are discussed. There is no significant difference observed in the dyn amic behavior and in the operating Voltages between the two cases. The degr adation mechanism is similar with the developing of dark line defects and a 1/t-like decrease in light intensity at constant current for t --> infinit y. The width of the dark line defects is in homoepitaxy almost constant in time, although their number is higher. This difference is also reflected in the lifetimes of our devices during lasing, which is in heteroepitaxy thre e minutes and about one second in homoepitaxy, for both in cw operation at room temperature.