Self-Powered UV-Near Infrared Photodetector Based on Reduced Graphene Oxide/n-Si Vertical Heterojunction.
A novel self-powered photodetector based on reduced graphene oxide (rGO)/n-Si p-n vertical heterojunction with high sensitivity and fast response time is presented. The photodetector contains a p-n vertical heterojunction between a drop-casted rGO thin film and n-Si. Contacts between the semiconductor layer (rGO, n-Si) and source-drain Ti/Au electrodes allow efficient transfer of photogenerated charge carriers. The self-powered UV-near infrared photodetector shows high sensitivity toward a spectrum of light from 365 to 1200 nm. Under the 600 nm illumination (0.81 mW cm-2), the device has a photoresponsivity of 1.52 A W-1, with fast response and recover time (2 ms and 3.7 ms), and the ON/OFF ratios exceed 104when the power density reaches ≈2.5 mW cm-2. The high photoresponse primarily arises from the built-in electric field formed at the interface of n-Si and rGO film. The effect of rGO thickness, rGO reduction level, and layout of rGO/n-Si effective contact area on device performance are also systematically investigated.
i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Ruoshui Road, Suzhou, 215123, China.
Guanghui
G
Li
Department of Environmental Science, Xi'an Jiaotong-Liverpool University, 111 Ren'ai Road, Suzhou, 215123, China.
Lin
L
Liu
i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Ruoshui Road, Suzhou, 215123, China.
Guan
G
Wu
i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Ruoshui Road, Suzhou, 215123, China.
Wei
W
Chen
Department of Environmental Science, Xi'an Jiaotong-Liverpool University, 111 Ren'ai Road, Suzhou, 215123, China.
Sujie
S
Qin
C&N Intl. Co. Ltd, Beijing, 102206, China. wangy@c-nintl.com.cn.|Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China. wangy@c-nintl.com.cn.
Yi
Y
Wang
i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Ruoshui Road, Suzhou, 215123, China. tzhang2009@sinano.ac.cn.
Ting
T
Zhang
graphene; p-n vertical heterojunction; photodetectors; self-powered