Defect structure of 〈100〉 dark lines in the active region of a rapidly degraded Ga1−xAlxAs LED

Abstract
The 〈100〉 dark‐line defects (DLD’s) in the active region of a rapidly degraded Ga1−xAlxAs LED were observed by transmission electron microscopy (TEM). Dislocation networks, which contain dislocation dipoles and a number of dislocation loops, were associated with 〈100〉 DLD’s. The dipole extended in the 〈100〉 or 〈210〉 direction and was extrinsic in character; its Burgers vector was a/2 〈011〉 inclined at 45° to the junction plane. These results were very similar to those of GaAs‐Ga1−xAlxAs double‐heterostructure (DH) lasers.