Fang–Howard wave function modelling of electron mobility in AlInGaN/AlN/InGaN/GaN double heterostructures*

Abstract

To study the electron transport properties in InGaN channel-based heterostructures, a revised Fang-Howard wave function is proposed by combining the effect of GaN back barrier. Various scattering mechanisms, such as dislocation impurity (DIS) scattering, polar optical phonon (POP) scattering, piezoelectric field (PE) scattering, interface roughness (IFR) scattering, deformation potential (DP) scattering, alloy disorder (ADO) scattering from InGaN channel layer, and temperature-dependent energy bandgaps are considered in the calculation model. A contrast of AlInGaN/AlN/InGaN/GaN double heterostructure (DH) to the theoretical AlInGaN/AlN/InGaN single heterostructure (SH) is made and analyzed with a full range of barrier alloy composition. The effect of channel alloy composition on InGaN channel-based DH with technologically important Al(In,Ga)N barrier is estimated and optimal indium mole fraction is 0.04 for higher mobility in DH with Al0.4In0.07Ga0.53N barrier. Finally, the temperature-dependent two-dimensional electron gas (2DEG) density and mobility in InGaN channel-based DH with Al0.83In0.13Ga0.04N and Al0.4In0.07Ga0.53N barrier are investigated. Our results are expected to conduce to the practical application of InGaN channel-based heterostructures.