A Theoretical Study on Electron Tunneling Current in Isotropic High-κ Dielectric Stack-Based MOS Capacitors with Charge Trapping

Abstract

Electron tunneling current in an isotropic metal-oxide-semiconductor (MOS) capacitor with a high-κ dielectric stack has been studied by considering the effect of charge trapping. The transmittance was analytically calculated by employing an Airy-wavefunction approach and including a coupling term between the transverse and longitudinal kinetic energies which is represented by an electron phase velocity in the gate. The transmittance was then applied to obtain tunneling currents in isotropic n+poly-Si/HfSiOxN/trap/SiO2/Si (100) MOS capacitors for different electron gate phase velocities and trap depths and widths. The calculated results show that the transmittance and tunneling current increase as the electron gate velocity decreases. In addition, the increase in the trap depth and width enhances the tunneling current.