SPECTRAL SHIFTS ASSOCIATED WITH DARK LINE DEFECTS IN DEGRADED II-VI LASER-DIODES

Spectral shifts associated with [100] dark line defects of degraded II -VI laser diodes based on ZnCdSe/ZnSSe/MgZnSSe separate confinement he terostructures have been studied by spatially resolved cathodoluminesc ence at room temperature. Dark line defects were induced by electron-b eam bombardment. Peak shifts as large as 2 nm were observed towards th e blue or the red depending on the local circumstances. Peak widths us ually became narrower after degradation. Redshifts and blueshifts are explained in terms of strain relaxation and Cd out-diffusion associate d locally with degradation, as well as the kinetic energy dependence o f the degradation-related carrier capture cross section. (C) 1998 Amer ican Institute of Physics. [S0003-6951(98)04114-X].