Carrier concentration dependence of ballistic mobility and mean free path in a nano-dimensional InAlAs/InGaAs single gate HEMT

Abstract

This paper presents an analytical model for mobility in nano-dimensional InAlAs/InGaAs single gate HEMT. Effect of increase in carrier concentration on ballistic mobility in the nano-dimensional device is presented. The model accounts for quantization effects by solving a one-dimensional (1D) time-independent Schrodinger equation in a nano-scale channel at equilibrium. The eigen energies, thus obtained are employed to evaluate the carrier concentration of the 2DEG in the channel at equilibrium i.e no gate bias applied. The carrier mobility in the short channel is then utilized to calculate the ballistic mean free path. The ballistic mean free path of the carrier in the channel region is found to be substantially larger than the long channel mean free path.