title: Boosting Hole Mobility in Coherently Strained [110]-Oriented Ge-Si Core-Shell Nanowires.
abstract: The ability of core-shell nanowires to overcome existing limitations of heterostructures is one of the key ingredients for the design of next generation devices. This requires a detailed understanding of the mechanism for strain relaxation in these systems in order to eliminate strain-induced defect formation and thus to boost important electronic properties such as carrier mobility. Here we demonstrate how the hole mobility of [110]-oriented Ge-Si core-shell nanowires can be substantially enhanced thanks to the realization of large band offset and coherent strain in the system, reaching values as high as 4200 cm2/(Vs) at 4 K and 1600 cm2/(Vs) at room temperature for high hole densities of 1019cm-3. We present a direct correlation of (i) mobility, (ii) crystal direction, (iii) diameter, and (iv) coherent strain, all of which are extracted in our work for individual nanowires. Our results imply [110]-oriented Ge-Si core-shell nanowires as a promising candidate for future electronic and quantum transport devices.
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands.|Department of Applied Physics, TU Eindhoven , Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Conesa-Boj
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands.|Department of Applied Physics, TU Eindhoven , Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
authors.forename: A
authors.initials: A
authors.lastname: Li
authors.affiliation: Department of Applied Physics, TU Eindhoven , Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
authors.forename: S
authors.identifier: 0000-0002-6606-9110
authors.initials: S
authors.lastname: Koelling
authors.affiliation: NanoElectronics Group, MESA Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Brauns
authors.affiliation: NanoElectronics Group, MESA Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: J
authors.initials: J
authors.lastname: Ridderbos
authors.affiliation: NanoElectronics Group, MESA Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: T T
authors.initials: TT
authors.lastname: Nguyen
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands.|Philips Innovation Services Eindhoven , High Tech Campus 11, 5656 AE Eindhoven, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Verheijen
authors.affiliation: Department of Applied Physics, TU Eindhoven , Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
authors.forename: P M
authors.initials: PM
authors.lastname: Koenraad
authors.affiliation: NanoElectronics Group, MESA Institute for Nanotechnology, University of Twente , P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: F A
authors.initials: FA
authors.lastname: Zwanenburg
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology , Lorentzweg 1, 2628 CJ Delft, The Netherlands.|Department of Applied Physics, TU Eindhoven , Den Dolech 2, 5612 AZ Eindhoven, The Netherlands.
authors.forename: E P A M
authors.identifier: 0000-0002-8264-6862
authors.initials: EP
authors.lastname: Bakkers
keywords: Nanowire; defect-free; epitaxy; germanium; mobility; silicon