AUTHOR=yiyun zhang , Zhang Yiyun , Pan Dong , Xiaoyan Yi , Jianhua Zhao , Jinmin Li 

TITLE=Negative Photoconductive Effects in Uncooled InAs Nanowire Photodetectors

JOURNAL=Frontiers in Physics

VOLUME=9

YEAR=2021

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.725680

DOI=10.3389/fphy.2021.725680

ISSN=2296-424X

ABSTRACT=<p>One-dimensional, direct, and narrow band gap indium arsenide (InAs) nanowires (NWs) have been emerging with great potentials for the next-generation wide-spectrum photodetectors. In this study, metal–semiconductor–metal (MSM) structure InAs NW-based photodetectors were fabricated by transferring MBE-grown NWs onto a sapphire substrate via a mechanical stamping method. These NW detectors exhibit strong negative photoconductive (NPC) effects, which are likely caused by the carrier dynamics in the “core-shell” structure of the NWs. Specifically, under the irradiation of a 405 nm violet laser, the maximum <italic>I</italic><sub><italic>dark</italic></sub>/<italic>I</italic><sub><italic>light</italic></sub> ratio reaches ∼10<sup>2</sup> and the NPC gain reaches 10<sup>5</sup> at a low bias voltage of 0.2 V. At room temperature, the rise and decay times of InAs NW devices are 0.005 and 2.645 s, respectively. These InAs NW devices with a high <italic>I</italic><sub><italic>dark</italic></sub>/<italic>I</italic><sub><italic>light</italic></sub> ratio and NPC gain can be potentially used in the field of vis/near-IR light communication in the future.</p>