Admittance and nonlinear capacitance of a multilayer metal-semiconductor structure

Abstract

Nonlinear properties of capacitance and frequency dependence of admittance for a multilayer metal-semiconductor structure are studied theoretically. It is shown that admittance of such structure depends on the frequency of a small probe signal. The voltage dependence of capacitance measured using a low-frequency probe signal can be nonmonotonic. The behavior of the structure’s capacitance at a large amplitude of external signal is studied. After some time from the instant of switching-on of the high-frequency signal, the system is found in a steady state with certain charge of the metal layer and predefined capacitance of the system. In the steady state, the charge of metal and the capacitance do not depend on the instantaneous value of the voltage; rather, they are governed by the signal’s amplitude.