Silicon interface passivation studied by modulated surface photovoltage spectroscopy

Abstract We demonstrate that the modulated surface photovoltage spectroscopy (modulated SPS) technique can be applied to investigate interface states in bandgap, i.e. passivation, of crystalline silicon coated with a downshift layer such as hydrogenated aluminum nitride embedded terbium ions by suppressing straylight cut-off filter. Different hydrogen contents influence spectra at photon energies below bandgap silicon. Modulated SPS reveals higher content there is lower signal and, thus, density defect states. Our experiments show become powerful tool for characterizing interfaces which cannot easily studied other methods.