Center Potential Based Analysis of Si and III-V Gate all around Field Effect Transistors (GAA-FETs)

Abstract

In this brief, the center potential based analysis of Si and AlGaN/GaN gate all around field effect transistors (GAA-FET) is presented. The center potential is calculated for different values of channel length, channel height, doping concentration, and thickness of oxide layer using numerical simulations and analytical modeling. The results obtained using numerical simulations through TCAD are validated and found in decent accord with the analytical modeling. The lower effective mass of the III-V channel material results in the lower density of states (DOS), so quantum capacitance reduces significantly in III-V GAA-FET as compared to Si. This small DOS of III-V directly results in a low sheet carrier concentration at a certain gate overdrive voltage for III-V GAA-FET. The analog and linearity/distortion parameters of III-V and Si GAA-FET are calculated and compared. The utility of the III-V GAA-FET extends in high speed and low power digital logic applications, RF design applications including low noise and very high frequency due to better electron transport properties than Si.