Passivation of the facets of 980 nm GaAs pump lasers by a pulsed UV laser-assisted technique

It is reported on the passivation of the mirror facets, opened in the air, of ridge waveguide InGaAs/GaAs/AlGaAs single quantum well (lambda = 980 nm) laser diodes. The passivation concept consists of two steps, namely, oxide removal by irradiation of the mirror facets with a pulsed KrF laser, immed iately followed by the deposition of a thin silicon layer. The experimental arrangement (the process operation and the aging behavior-resistance to ca tastrophic optical damage) of the lasers thus treated are described. The st ructural modification of the laser facets, as probed by micro-Raman spectro scopy and Rutherford backscattering spectroscopy, and the calibration techn ique used to assess the rate of oxide removal are also presented.