Characterization of InGaAsP surface corrugation used for distributed feedback lasers by means of Raman spectroscopy

Abstract
Thermally deformed surface corrugations on both an InP substrate and an InGaAsP layer have been analyzed by means of x-ray photoelectron spectroscopy and laser Raman spectroscopy. From the spectra of the deformed surface corrugations on an InP substrate on which a GaAs wafer was placed during its heat treatment, it has been found that material formed in the grooves is an InGaAsP alloy single crystal.