title: Highly ordered vertical GaAs nanowire arrays with dry etching and their optical properties.
abstract: We report fabrication methods, including metal masks and dry etching, and demonstrate highly ordered vertical gallium arsenide nanowire arrays. The etching process created high aspect ratio, vertical nanowires with insignificant undercutting from the mask, allowing us to vary the diameter from 30 nm to 400 nm with a pitch from 250 nm to 1100 nm and length up to 2.2 μm. A diameter to pitch ratio of ∼68% was achieved. We also measured the reflectance from the nanowire arrays and show experimentally diameter-dependent strong absorption peaks resulting from resonant optical mode excitations within these nanowires. The reflectance curves match very well with simulations. The work done here paves the way towards achieving high efficiency solar cells and tunable photodetectors using III-V nanowires.
authors.affiliation: Department of Electrical and Computer Engineering, University of Waterloo, 200 University Ave West, Waterloo, ON, N2L 3G1, Canada. Waterloo Institute of Nanotechnology, University of Waterloo, 200 University Ave West, Waterloo, ON, N2L 3G1, Canada.
authors.forename: Navneet
authors.initials: N
authors.lastname: Dhindsa
authors.forename: Andrew
authors.initials: A
authors.lastname: Chia
authors.forename: Jonathan
authors.initials: J
authors.lastname: Boulanger
authors.forename: Iman
authors.initials: I
authors.lastname: Khodadad
authors.forename: Ray
authors.initials: R
authors.lastname: LaPierre
authors.forename: Simarjeet S
authors.initials: SS
authors.lastname: Saini