Passivation of Edge States in Etched InAs Sidewalls

Abstract

We investigate different methods of passivating sidewalls of wet etched InAs heterostructures in order to suppress inherent edge conduction that is presumed to occur due to band bending at the surface leading to charge carrier accumulation. Passivation techniques including sulfur, positively charged compensation dopants and plasma enhanced chemical vapor deposition of ${\mathrm{SiN}}_{\mathrm{x}}$ do not show an improvement. Surprisingly, atomic layer deposition of ${\mathrm{Al}}_2{\mathrm{O}}_3$ leads to an increase in edge resistivity of more than an order of magnitude. While the mechanism behind this change is not fully understood, possible reasons are suggested.

References in corpus (3)

• Quantum Spin Hall Effect in Inverted Type II Semiconductors
• Edge transport in InAs and InAs/GaSb quantum wells
• Influence of etching processes on electronic transport in mesoscopic InAs/GaSb quantum well devices

Cited by in corpus (3)

• Counterflowing edge current and its equilibration in quantum Hall devices with sharp edge potential: Roles of incompressible strips and contact configuration
• Gate-tunable Electronic Transport in p-type GaSb Quantum Wells
• Few-electron Single and Double Quantum Dots in an InAs Two-Dimensional Electron Gas