Wafer-Scale Synthesis of High-Quality Semiconducting Two-Dimensional Layered InSe with Broadband Photoresponse.
Large-scale synthesis of two-dimensional (2D) materials is one of the significant issues for fabricating layered materials into practical devices. As one of the typical III-VI semiconductors, InSe has attracted much attention due to its outstanding electrical transport property, attractive quantum physics characteristics, and dramatic photoresponse when it is reduced to atomic scale. However, scalable synthesis of single phase 2D InSe has not yet been achieved so far, greatly hindering further fundamental studies and device applications. Here, we demonstrate the direct growth of wafer-scale layered InSe nanosheets by pulsed laser deposition (PLD). The obtained InSe layers exhibit good uniformity, high crystallinity with macro texture feature, and stoichiometric growth by in situ precise control. The characterization of optical properties indicates that PLD grown InSe nanosheets have a wide range tunable band gap (1.26-2.20 eV) among the large-scale 2D crystals. The device demonstration of field-effect transistor shows the n-type channel feature with high mobility of 10 cm2V-1s-1. Upon illumination, InSe-based phototransistors show a broad photoresponse to the wavelengths from ultraviolet to near-infrared. The maximum photoresponsivity attains 27 A/W, plus a response time of 0.5 s for the rise and 1.7 s for the decay, demonstrating the strong and fast photodetection ability. Our findings suggest that the PLD grown InSe would be a promising choice for future device applications in the 2D limit.
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.|The Hong Kong Polytechnic University Shenzhen Research Institute , Shenzhen 518057, P. R. China.
Zhibin
Z
Yang
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.|The Hong Kong Polytechnic University Shenzhen Research Institute , Shenzhen 518057, P. R. China.
Wenjing
W
Jie
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.
Chun-Hin
CH
Mak
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.
Shenghuang
S
Lin
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.
Huihong
H
Lin
Analytical and Testing Center, South China University of Technology , Guangzhou 510641, P. R. China.
Xianfeng
X
Yang
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.
Feng
F
Yan
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.
Shu Ping
SP
Lau
Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Hong Kong P. R. China.|The Hong Kong Polytechnic University Shenzhen Research Institute , Shenzhen 518057, P. R. China.
Jianhua
0000-0002-6186-5169
J
Hao
InSe; monolayer; photoresponse; pulsed laser deposition; wafer-scale synthesis