Surface states and buried interface states studies in semiconductors by photothermal deflection spectroscopy

Abstract
A method is presented which, through the simultaneous analysis of the photothermal deflection spectroscopy (PDS) signal amplitude and phase spectra, enables to detect surface states and buried interface states and to measure their absorption. A theoretical model for the PDS signal suitable for the present approach has been developed and the measurements were performed on single crystalline GaAs wafers with ion-implanted layers on the front surface or buried beneath the front surface.