A review of the electrical properties of semiconductor nanowires: Insights gained from terahertz conductivity spectroscopy

Journal article

Accurately measuring and controlling the electrical properties of semiconductor nanowires is of paramount importance in the development of novel nanowire-based devices. In light of this, terahertz conductivity spectroscopy has emerged as an ideal non-contact technique for probing nanowire electrical conductivity and is showing tremendous value in the targeted development of nanowire devices. THz spectroscopic measurements of nanowires enable charge carrier lifetimes, mobilities, dopant concentrations and surface recombination velocities to be measured with high accuracy and high throughput in a contact-free fashion. This review spans seminal and recent studies of the electronic properties of nanowires using terahertz spectroscopy. A didactic description of terahertz time-domain spectroscopy, optical pump–terahertz probe spectroscopy, and their application to nanowires is included. We review a variety of technologically important nanowire materials, including GaAs, InAs, InP, GaN and InN nanowires, Si and Ge nanowires, ZnO nanowires, nanowire heterostructures, doped nanowires and modulation-doped nanowires. Finally, we discuss how terahertz measurements are guiding the development of nanowire-based devices, with the example of single-nanowire photoconductive terahertz receivers.

Authors: Joyce, H; Boland, J; Davies, C; Baig, S; Johnston, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Institute of Physics
• Journal: Semiconductor Science and Technology
• Volume: 31
• Issue: 10
• Publication date: 2016-09-01
• Acceptance date: 2016-07-13
• DOI: 10.1088/0268-1242/31/10/103003
• ISSN: 0268-1242 and 1361-6641
• Keywords: terahertz spectroscopy; InP; mobility; GaAs; nanowire; InAs; silicon; ultrafast; spectroscopy; surface recombination velocity; ZnO; contact-free; germanium; Semiconductor; lifetime; III–V