An investigation of the silicon—Sapphire interface using the MIS capacitance method

Measurements of the MIS capacitance as a function of voltage were carried out on aluminum-sapphire-silicon structures. The results were used to determine the doping of the silicon and the interface-state density and flat-band charge density at the silicon-sapphire interface. The density of states function Ds(cm^-2eV^-1) is found to be qualitatively similar to that reported for the Si-SiO2interface but is larger in magnitude by a factor of 5-10.