Conductance study of silicon nitride/InP capacitors with an In2S3 interface control layer

Abstract

Conductance measurements of the SiNx/n-InP interface with an In2S3 interface control layer show the presence of electron traps, with capture cross section of 5.6×10−18 cm2, near the conduction band that increase in density towards the band edge. Carrier accumulation at the interface and response from bulk traps lead to single time constant conductance peaks. The loss is dominated by interface states in accumulation and by bulk states in depletion and weak inversion. The study indicates that low interface trap densities are achieved in the InP band gap for Ec−E≳0.24 eV in agreement with capacitance-voltage results.