Analysis of Improved Two‐dimensional Electron Gas Mobility in InAlN/AlN/InGaN HEMT with GaN Interlayer

In this work, we systematically elucidate the physical mechanism of GaN interlayer for improving 2DEG mobility in InGaN channel by using an inter-subband scattering model. The model takes into account various scattering mechanisms between the first four subbands, in which the wavefunction of each subband is obtained by self-consistently solving 1D Schr o ¨ dinger-Poisson equations. The total 2DEG mobility is obtained by averaging the subband mobility by the percentage of electrons in the different subbands. The effect of introducing different thicknesses of GaN interlayer on the mobility limited by various scattering mechanisms is discussed in detail, especially polar optical phonon scattering and alloy disorder scattering. The calculated results are well supported by the reported experimental data, validating the correctness of the model.This article is protected by copyright. All rights reserved.