Activation energy of nonradiative processes in degraded II-VI laser diodes

摘要

A spatially resolved cathodolluminescence study of 〈100〉 dark line defects (DLDs) of degraded II-VI laser diodes based .on a ZnCdSe/ZnMgSSe separate confinement heterostructure has been carried out at temperatures between room temperature and 8 K. Cathodohuminescence line scans were used to measure the change of contrasts between the DLDs and the adjacent material; The contrast decreased with decreasing temperature, which suggests that the nonradiative recombination processes associated with DLDs are thermally activated. Activation energies were found to be about 16 and 6 meV for temperatures above and below 200 K. respectively, which may reflect a transition between free carriers and bound excitons at this temperature. # 1997 American Institute of Physics. S0003-6951 (97)00205-2