Negative capacitance of native oxide films on (0001) InSe fracture surfaces

Abstract

A negative capacitance has been found at low frequencies (1 × 105 to 3.7 × 107 Hz) in native oxide films grown in air on InSe(0001) fracture surfaces. The films have the form of a dielectric Se2O5 matrix containing indium metal nanoinclusions. Resistivity and capacitance measurements at frequencies from 100 Hz to 37 MHz have been used to study the polarization mechanisms for the native oxide films in In/native oxide/InSe structures. The results indicate that a negative capacitance (inductive impedance) of native oxide films may be due to carrier capture at traps located at the many metal—dielectric interfaces.