Direct Photoelectric Measurement of the Interface-State Density at a Pt-Si Interface

From infrared photoelectric measurements, we have obtained a density of the interface states lying between 0.745 and 0.825 eV from the silicon conduction band at a Pt-Si interface. We show the following: The transitions occur preponderantly from a level {~} 0.3 eV below the platinum Fermi level; a peak exists in the interface-state density at 0.79 eV from the silicon conduction band; and the pseudo Fermi level in the semiconductor moves up with forward bias.