Bias-controlled spectral response in GaN/AlN single-nanowire ultraviolet photodetectors

Abstract

We present a study of GaN single-nanowire ultraviolet photodetectors with an embedded GaN/AlN superlattice. The heterostructure dimensions and doping profile were designed in such a way that the application of positive or negative bias leads to an enhancement of the collection of photogenerated carriers from the GaN/AlN superlattice or from the GaN base, respectively, as confirmed by electron beam-induced current measurements. The devices display enhanced response in the ultraviolet A ($\approx$ 330-360 nm) / B ($\approx$ 280-330 nm) spectral windows under positive/negative bias. The result is explained by correlation of the photocurrent measurements with scanning transmission electron microscopy observations of the same single nanowire, and semi-classical simulations of the strain and band structure in one and three dimensions.

This document is the unedited Author's version of a Submitted Work that was subsequently accepted for publication in Nano Letters (2017), copyright (C) American Chemical Society after peer review. To access the final edited and published work see http://doi.org/10.1021/acs.nanolett.7b01118

References in corpus (1)

• Long-lived excitons in GaN/AlN nanowire heterostructures

Cited by in corpus (2)

• Nanowire photodetectors based on wurtzite semiconductor heterostructures
• Effect of the nanowire diameter on the linearity of the response of GaN-based heterostructured nanowire photodetectors