Analysis of In_0.53Ga_0.47As n-MOSFET Characteristics using Quantum Drift Diffusion Model

Abstract

In this study, we have analyzed the I_d-V_g characteristics of In_0.53Ga_0.47As n-MOSFETs using a quantum drift-diffusion (QDD) model with Fermi-Dirac (FD) distribution. In_0.53Ga_0.47As is a material with a smaller energy band gap than that of Si. The I_d-V_g characteristics using FD distribution are compared with that using Maxwell-Boltzmann (MB) distribution. The difference of the characteristics between FD and MB distributions is observed as the applied gate voltage is increased. To investigate the difference, we have evaluated the electron density distributions and electrostatic potentials. We have calculated the energy difference between the bottom of the conduction band and the Fermi level derived from the electrostatic potential. It is found that the energy difference becomes smaller as the gate voltage is increased. The energy difference affects the difference in the I_d-V_g characteristics. We have clarified that the relationship between the energy band gap and quantum confinement effects. It is found that it is necessary for the device simulation model using FD distribution to simulate MOSFETs with semiconductor materials with a smaller energy band gap.