Degradation mechanism of (Al · Ga)As double-heterostructure laser diodes

Abstract

This paper reports new observations in degraded (Al · Ga)As double-heterostructure (DH) laser diodes and proposes a mechanism of short-term ([inverted lazy s] 100 h) degradation characteristic to DH structures. Degradation is seen localized as ``dark lines'' of certain crystalline orientations in electroluminescent patterns, as well as junction current patterns using an SEM. X-ray measurement showed internal strain due to heteromismatch. It is suggested that the internal stress accelerates development of the dark lines, which is likely to be a crystalline defect caused by thermal stresses.