Annealing effect on the dc transport mechanism in dysprosium oxide films grown on Si substrates

Abstract

Crystalline Dy oxide thin films prepared on Si(p) substrates were annealed in vacuum and air at different temperatures and investigated by x-ray diffraction (XRD). Their capacitance-gate voltage characteristics were used to determine the charge densities in the samples and the voltage drop across the oxide layer itself in terms of gate voltage. The surface charge density was device-grade, on the order of 1011 cm−2. The dc current-voltage characteristic measurements show that the main mechanism controlling the current flow is the Richardson-Schottky (RS) mechanism. Parameters of the RS model, such as field-lowering coefficients and dynamic relative permittivity, were determined. The leakage current density of the samples was studied as a function of temperature from 293 to 400 K, and activation energies were determined.