We have investigated the laser-induced damage morphology using femtosecond laser pulse at 0.8 μm on InGaAs surface.
Damage morphology has been analyzed by a scanning electron microscope (SEM). The diameter of the damage spot
increased, on increasing the laser fluence. The damage morphology at the central portion differs from the one at the
periphery of the spot. The roughness and the step height of the damage spot were measured through XP Stylus Profiler
which is a computerized, high-sensitivity surface profiler. The depth morphology of the damage spot shows the ablation
of material. After the laser-induced damage studies of material, laser-induced damage in 256 elements front-illuminated
InGaAs detectors arrays are reported. Prior to irradiation, the dark current is dominated by the diffusion current
indicating that the junctions are of good quality. The dark
current-voltage curves before laser irradiation are compared
with the ones irradiated at different laser power density and we find that the laser irradiation may produce an increase in
the dark current. The spectral response was also measured to evaluate the laser-induced effects on the detectors.