Semiconductor photodiodes in the VUV: Determination of layer thicknesses and design criteria for improved devices

Abstract Semiconductor photodiodes are shown to be suited as detectors in the vacuum ultraviolet (VUV) spectral region. The spectral responsivity can be described with a simple model, which requires only the knowledge of the thicknesses of the dead layer and of the sensitive volume. These parameters are determined by measuring the angular dependence of the photocurrents. The spectral responsivities calculated with these parameters are in agreement with radiometric measurements of the spectral responsivity. Design criteria for semiconductor detectors to be used in various parts of the VUV are derived from the measurements.