A van der Waals pn heterojunction with organic/inorganic semiconductors

Journal Article · Mon Nov 02 04:00:00 EST 2015 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4935028· OSTI ID:22486011

He, Daowei; Yang, Ziyi; Wu, Bing; Xu, Bingchen; Zhang, Yuhan; Li, Yun; Shi, Yi; Wang, Xinran ^[1]; Pan, Yiming; Wang, Baigeng ^[2]; Nan, Haiyan; Luo, Xiaoguang; Ni, Zhenhua ^[3]; Gu, Shuai; Zhu, Jia ^[4]; Chai, Yang ^[5]

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1. National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)
2. National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093 (China)
3. Department of Physics, Southeast University, Nanjing 211189 (China)
4. College of Engineering and Applied Science, Nanjing University, Nanjing 210093 (China)
5. Department of Applied Physics, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)

van der Waals (vdW) heterojunctions formed by two-dimensional (2D) materials have attracted tremendous attention due to their excellent electrical/optical properties and device applications. However, current 2D heterojunctions are largely limited to atomic crystals, and hybrid organic/inorganic structures are rarely explored. Here, we fabricate the hybrid 2D heterostructures with p-type dioctylbenzothienobenzothiophene (C{sub 8}-BTBT) and n-type MoS{sub 2}. We find that few-layer C{sub 8}-BTBT molecular crystals can be grown on monolayer MoS{sub 2} by vdW epitaxy, with pristine interface and controllable thickness down to monolayer. The operation of the C{sub 8}-BTBT/MoS{sub 2} vertical heterojunction devices is highly tunable by bias and gate voltages between three different regimes: interfacial recombination, tunneling, and blocking. The pn junction shows diode-like behavior with rectifying ratio up to 10{sup 5} at the room temperature. Our devices also exhibit photovoltaic responses with a power conversion efficiency of 0.31% and a photoresponsivity of 22 mA/W. With wide material combinations, such hybrid 2D structures will offer possibilities for opto-electronic devices that are not possible from individual constituents.

• OSTI ID: 22486011
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 18 Vol. 107; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHANNELING
EFFICIENCY
ELECTRIC POTENTIAL
EPITAXY
HETEROJUNCTIONS
HYBRIDIZATION
INTERFACES
MOLECULAR CRYSTALS
MOLYBDENUM SULFIDES
OPTICAL PROPERTIES
PHOTOVOLTAIC EFFECT
RECOMBINATION
SEMICONDUCTOR MATERIALS
TUNNEL EFFECT
TWO-DIMENSIONAL SYSTEMS
VAN DER WAALS FORCES