Abstract

We previously reported that the dominant degradation mechanism in 1.3-μm InGaAsP BH lasers and LEDs is an increase in a saturable nonradiative current, as revealed by measurement of radiative and nonradiative currents using a highly sensitive carrier lifetime technique.¹ We propose that the physical origin of this degradation mechanism is increased interfacial recombination due to current-induced migration ot detects to the heterointer-face. This model quantitatively explains all changes observed after aging: increased threshold current; decreased forward voltage at low bias; reduced carrier lifetime; and decreased facet and spontaneous emission. Furthermore, this model is found to apply universally to a wide variety of device geometries, including six types of buried heterostructure laser and planar LED. Additional support for this model is provided by other recent observations suggesting interface degradation in BH lasers² and by earlier measurements of interfacial recombination in AlGaAs/GaAs, which showed that it could contribute substantially to the threshold current.³

© 1988 Optical Society of America