Raman and photoluminescence analyses of the crystalline InAlAs layer grown on InP substrate

Photoluminescence and Raman measurements are used to characterize the In x Al 1‐x As (0.48 < × <0.573)epilayers grown on InP substrate by molecular beam epitaxy. It is found that as In composition, x, deviates too much from 0.52, misfit dislocations may be introduced. These dislocations will dramatically reduce the radiative efficiency of the InAlAs epilayers. Raman spectra become broader and more asymmetry due to alloy potential fluctuations as the mismatch becomes large.