title: Manipulating Surface States of III-V Nanowires with Uniaxial Stress.
abstract: III-V compound semiconductors are indispensable materials for today's high-end electronic and optoelectronic devices and are being explored for next-generation transistor logic and quantum technologies. III-V surfaces and interfaces play the leading role in determining device performance, and therefore, methods to control their electronic properties have been developed. Typically, surface passivation studies demonstrated how to limit the density of surface states. Strain has been widely used to improve the electronic transport properties and optoelectronic properties of III-Vs, but the potential of this technology to modify the surface properties still remains to be explored. Here we show that uniaxial stress induces a shift in the energy of the surface states of III-V nanowires, modifying their electronic properties. We demonstrate this phenomenon by modulating the conductivity of InAs nanowires over 4 orders of magnitude with axial strain ranging between -2.5% in compression and 2.1% in tension. The band bending at the surface of the nanostructure is modified from accumulation to depletion reversibly and reproducibly. We provide evidence of this physical effect using a combination of electrical transport measurement, Raman spectroscopy, band-structure modeling, and technology computer aided design (TCAD) simulations. With this methodology, the deformation potentials for the surface states are quantified. These results reveal that strain technology can be used to shift surface states away from energy ranges in which device performance is negatively affected and represent a novel route to engineer the electronic properties of III-V devices.
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: G
authors.identifier: 0000-0001-7066-0416
authors.initials: G
authors.lastname: Signorello
authors.affiliation: Integrated Systems Laboratory, Department of Electrical Engineering and Information Technology, ETH Zürich , 8092 Zürich, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Sant
authors.affiliation: Electron Microscopy Center, EMPA, Swiss Federal Laboratories for Materials Science and Technology , 8600 Dübendorf, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Bologna
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Schraff
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: U
authors.initials: U
authors.lastname: Drechsler
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: H
authors.identifier: 0000-0002-0228-4268
authors.initials: H
authors.lastname: Schmid
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Wirths
authors.affiliation: Electron Microscopy Center, EMPA, Swiss Federal Laboratories for Materials Science and Technology , 8600 Dübendorf, Switzerland.
authors.forename: M D
authors.initials: MD
authors.lastname: Rossell
authors.affiliation: Integrated Systems Laboratory, Department of Electrical Engineering and Information Technology, ETH Zürich , 8092 Zürich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Schenk
authors.affiliation: IBM Research - Zurich , 8803 Rüschlikon, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Riel
keywords: InAs nanowire; Uniaxial stress; charge modulation; giant gauge-factor; surface accumulation; surface states