High mobility In0.53Ga0.47As quantum-well metal oxide semiconductor field effect transistor structures

Abstract

In this paper, we demonstrate high electron mobility In_0.53Ga_0.47As quantum-well metal oxide semiconductor field effect transistor (MOSFET) structures. The Al₂O₃ (gate dielectric)/ In_0.53Ga_0.47As-In_0.52Al_0.48As (barrier)/In_0.53Ga_0.47As (channel) structures were fabricated, and the mobility was obtained by Hall measurements. The structures with in-situ chemical vapor deposition (CVD) Al₂O₃ displayed higher mobility than identical structures fabricated with in situ atomic layer deposition Al₂O₃, which indicates that CVD process resulted in a lower Al₂O₃/In_0.53Ga_0.47As interfacial defect density. A gate bias was applied to the structure with CVD Al₂O₃, and a peak mobility of 9243 cm²/V s at a carrier density of 2.7 × 10¹² cm⁻² was demonstrated for the structure with a 4 nm In_0.53Ga_0.47As-In_0.52Al_0.48As barrier. A model based on internal phonon scattering and interfacial defect coulomb scattering was developed to explain the experimental data and predict the mobility of In_0.53Ga_0.47As MOSFET structures.