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arXiv · 1310.0436

NIR Schottky Photodetectors Based on Individual Single-Crystalline GeSe Nanosheet

Bablu Mukherjee·Yongqing Cai·Hui Ru Tan·Yuan Ping Feng·Eng Soon Tok·Chorng Haur Sow
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Abstract

We have synthesized high-quality, micrometer-sized, single-crystal GeSe nanosheets using vapor transport and deposition techniques. Photoresponse is investigated based on mechanically exfoliated GeSe nanosheet combined with Au contacts under a global laser irradiation scheme. The nonlinearship, asymmetric, and unsaturated characteristics of the I-V curves reveal that two uneven back-to-back Schottky contacts are formed. First-principles calculations indicate that the occurrence of defects-induced in-gap defective states, which are responsible for the slow decay of the current in the OFF state and for the weak light intensity dependence of photocurrent. The Schottky photodetector exhibits a marked photoresponse to NIR light illumination at a wavelength of 808 nm. The significant photoresponse and good responsitivity suggests its potential applications as photodetectors.

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Bablu Mukherjee, Yongqing Cai, Hui Ru Tan, Yuan Ping Feng, Eng Soon Tok, Chorng Haur Sow. 2013-10-01. NIR Schottky Photodetectors Based on Individual Single-Crystalline GeSe Nanosheet. https://doi.org/10.1021/am402550s

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