CONDUCTANCE TECHNIQUE MEASUREMENTS OF THE DENSITY-OF-STATES BETWEEN SI AND ZNS GROWN BY MOLECULAR-BEAM EPITAXY

Electrical measurements have been performed on Al/ZnS/p-Si diodes, where the ZnS film was grown using the molecular beam epitaxy process. Capacitance-voltage data confirm that the ZnS layer is conducting as shown by the fall of capacitance in accumulation and the associated feature of deep depletion that is frequency independent. A wide dispersion of capacitance at different ac signal frequencies is observed in depletion. Also, admittance measurements are taken, using the conductance technique. The discrete energy-state model provided the best fit to the admittance data, inherently implying a low defect interface has been created. The density of interface states varies between 8.2 X 10(10) cm-2 eV-1 at the Si Fermi-level and 2.7 X 10(10) cm-2 eV-1 at the Si midgap.