Effect of Depletion Layer on the Total Mobility of AlGaN/GaN High Electron Mobility Transistors

An analytical, numerical model for the total mobility of AlGaN/GaN based high electron mobility transistors has been developed that is capable to predict accurately the effects of depletion layer thickness on the total mobility in different temperature, gate source biases and two dimensional electron gas density. Salient features of the model are incorporated of fully and partially occupied sub-bands in the interface quantum well, combined with a self-consistent solution of the Schrodinger and Poisson equations. In addition traps effects in the surface, interface and buffer layers, current in AlGaN barrier and three dimensional electron gas mobilitiy in the barrier of AlGaN and are also taking in to account. The calculated model results are in very good agreement with existing experimental data for high electron mobility transistors device.