1.Shanghai Normal University， Shanghai 200234， China;2.State Key Laboratory of Infrared Physics， Shanghai Institute of Technical Physics， Chinese Academy of Sciences， Shanghai 200083， China
Supported by National Natural Science Foundation(61474130) and Shanghai Natural Science Foundation（ 19ZR1465400, 18590780100, 19590711600）
The low intrinsic absorption and the existence of the inherent defects hamper the monoatomic layer graphene from being a high-performance photoelectric material, which leads to the strategy to form heterostructure by combining graphene with semiconductor materials. In this work, a graphene/GaAs heterostructure based photodetector has been designed and fabricated, in which the two-dimensional electron gas are enhanced to improve the photoresponse ability at the band of sub-millimeter and Terahertz (THz) wave ranging from 20 GHz to 0.12 THz. Under 25 GHz radiation, the responsivity of photodetector at room temperature (RT) reaches 20.6 V?W-1, with the response time of 9.8 μs and the noise equivalent power (NEP) of 3.2×1010 W?Hz-1/2 under a bias of 400 mV. At 0.12 THz, the responsivity is determined to be 4.6 V?W-1, with the response time of 10 μs. And a NEP of 1.4×10-9 W?Hz-1/2 can be achieved under the bias of 400 mV. These results exhibit great application potential for the graphene/GaAs heterostructure based THz photodetectors.
XU Kai-Qi, XU Huang, ZHANG Jia-Zhen, WU Xiang-Dong, YANG Lu-Han, ZHOU Jie, LIN Fang-Ting, WANG Lin, CHEN Gang. Graphene/GaAs heterostructure based Millimeter/Terahertz wave photodetector[J]. Journal of Infrared and Millimeter Waves,2020,39(5):533~539Copy