LASER OPERATION-INDUCED MIGRATION OF BERYLLIUM AT MIRRORS OF GAAS ALGAAS LASER-DIODES/

Laser operation-induced migration of beryllium at laser mirrors was st udied by electron-beam-induced current. The devices investigated were single quantum well graded index separate confinement GaAs/AlGaAs ridg e geometry laser diodes. In these devices, an operation-induced displa cement of the p-n junction towards the n-type cladding has been observ ed close to the mirrors. A similar effect was induced by electron irra diation of the mirror facets in a scanning electron microscope. These effects have been attributed to recombination-enhanced diffusion/migra tion of beryllium from the p-type cladding. We have measured the diffu sion coefficient of beryllium and, from this value, have estimated the average mirror temperature during laser operation. This temperature w as found to be in excellent agreement with recently published measured mirror temperatures.