Microscopic electronic structure and growth mode of Sn/InSb(111) interfaces

Abstract

The electronic properties and growth mode of Sn/InSb(111) interfaces have been investigated by angular resolved photoemission spectroscopy (ARUPS), high energy electron diffraction (RHEED), and work function measurements. For Sn coverages of ∼1 ML the Fermi level is pinned at the bottom of the conduction band. The interfacial growth is heteroepitaxial and extends to a thickness of ∼5 ML of Sn. This is followed by the formation of diamond structured α-Sn up to ∼40 ML. Beyond this thickness three dimensional island growth starts and the films are a mixture of semiconducting α-Sn and metallic β-Sn. Above ∼120 ML Sn, the surface region consists of pure β-Sn while due to a strong substrate stabilization effect the interface region still consists of the α-Sn phase.

Epitaxially Driven Phase Selectivity of Sn in Hybrid Quantum Nanowires

“…Unleashing the potential of either of the two Sn phasesand excluding the potential for unwanted behaviorsrequires phase-pure crystal growth, which is a challenge in thin films. ,− In particular, the presence of α-Sn significantly reduces the yield of superconducting devices, and phase-mixed materials present problems with regard to fabrication. While research has been undertaken on crystal phase stability in bulk Sn, ,,,,,− a comprehensive study of nanoscale Sn phase formation on semiconductor nanowires (NWs) is yet to be performed. Such knowledge is crucial to determining selective phase growth and controlling the interface properties of the Sn-based hybrid quantum heterostructures.…”