Integrated High-Performance Infrared Phototransistor Arrays Composed of Nonlayered PbS-MoS2Heterostructures with Edge Contacts.
Molybdenum disulfide (MoS2) has attracted a great deal of attention in optoelectronic applications due to its high mobility, low off-state current and high on/off ratio. However, its intrinsic large bandgap limits its application in infrared detection. Here, we have developed a high-performance infrared photodetector by integrating nonlayered PbS and layered MoS2nanostructures via van der Waals epitaxy. Density functional theory (DFT) calculations indicate that PbS nanoplates are in contact with MoS2edges through strong chemical hybridization, which is expected to offer a fast transmission path for carriers that enhances the response speed. The phototransistor exhibits a fast response (τrising= τdecay= 7.8 ms) as well as high photoresponsivity (4.5 × 104A·W-1) and Ilight/Idark(1.3 × 102) in the near-infrared spectral region at room temperature. In particular, the detectivity (D*) is as high as 3 × 1013Jones, which is even better than that of commercial Si and InGaAs photodetectors. Furthermore, by controlling the growth and microfabrication patterning, periodic device arrays of PbS-MoS2that are capable of infrared detection are achieved on Si/SiO2substrates. Our work provides a possible method for the integration of photodetector arrays on Si-based electronic devices and lays a solid foundation for the practical applications of MoS2-based devices in the future.
University of Chinese Academy of Sciences , Beijing 100049, China.
Yao
Y
Wen
University of Chinese Academy of Sciences , Beijing 100049, China.
Lei
L
Yin
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology , Beijing 100029, China.
Peng
P
He
Zhenxing
Z
Wang
State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing , Beijing 100083, China.
XianKun
X
Zhang
Department of Electrical and Computer Engineering, National University of Singapore , 117576 Singapore.
Qisheng
Q
Wang
University of Chinese Academy of Sciences , Beijing 100049, China.
Tofik Ahmed
TA
Shifa
University of Chinese Academy of Sciences , Beijing 100049, China.
Kai
K
Xu
University of Chinese Academy of Sciences , Beijing 100049, China.
Fengmei
F
Wang
Xueying
X
Zhan
University of Chinese Academy of Sciences , Beijing 100049, China.
Feng
F
Wang
Chao
C
Jiang
Jun
J
He
edge contact; infrared phototransistor; integration; nonlayered PbS−MoS2 heterostructure