COMPARISON OF DEGRADATION CAUSED BY DISLOCATION-MOTION IN COMPOUND SEMICONDUCTOR LIGHT-EMITTING DEVICES

Dislocation glide velocities in GaAlAs/GaAs, InGaAsP/InP, and GaN-base d light-emitting devices are estimated. These results are consistent w ith device degradation rates related to dislocation motion. It is clar ified that the long lifetime of GaN-based devices with high dislocatio n density is principally due to extremely small dislocation mobility, partly due to small shear stress for dislocation motion, and due littl e to the radiation enhancement effect. (C) 1997 American Institute of Physics.