Gate Tunable InSb Quantum Well Structures grown on GaSb (001)

Study of quantum well structures with InSb channels is of special interest to the field of spintronics and quantum computing due to the strong spin orbit coupling and large g-factor of InSb. Gate control of InSb quantum wells is a necessary component in construction of an InSb based Spin-Field Effect Transistor. In this work, InSb quantum well structures have been grown on lattice mismatched GaSb substrates by Molecular Beam Epitaxy. Magneto-transport measurements at low temperatures have been used to investigate the influence of gate voltage on electron mobility and density. A conventional metal top gate, separated from the III-V structure with an Atomic Layer Deposited insulating dielectric, has been used. Use of the conducting GaSb substrate as a potential, bottom gate electrode has also been investigated. Surface morphology of as-grown films has been studied using Atomic Force Microscopy.