Defect structure of degraded heterojunction GaAlAs−GaAs lasers

Abstract

Transmission electron microscopy has been used to study the defects associated with the degradation of broad−contact geometry double−heterostructure lasers. Two different types of dislocation networks have been observed close to the active region of the degraded device having Burgers vectors of (a/2) 〈011〉 and a〈001〉. Both networks have been shown to be of interstitial character.