ON THE OPTICAL AND ELECTRICAL PROPERTIES OF DYSPROSIUM AND YTTERBIUM MONOPHOSPHIDES

Dysprosium and ytterbium monophosphides were prepared by solid state reaction. Their crystal structure, energy gaps, resistivitY and Hall coefficient were investigated by x-ray powder diffraction, absorption spectromotry, four-probe and Van de Pauw method. The monophosphides were found to be N-type semiconductor with energy gaps of 1.15eV for DyP and 1.30eV for YbP, resistivities 10-2Ω-cm, carrier concentrations of 1018-1019cm-3 and corresponding Hall mobilities of 8.5-80cm2/v.s. The p-n junction is formed on DYP/Si and YbP/Si and it shows a rcctifYing character. Possible energy band schemes are Proposed which well explain the optical and electrical ProPerties of the compounds.