A van der Waals pn heterojunction with organic/inorganic semiconductors

Daowei He; Yiming Pan; Haiyan Nan; Shuai Gu; Ziyi Yang; Bing Wu; Xiaoguang Luo; Bingchen Xu; Yuhan Zhang; Yun Li; Zhenhua Ni; Baigeng Wang; Jia Zhu; Yang Chai; Yi Shi; Xinran Wang

arXiv · 1511.02361

A van der Waals pn heterojunction with organic/inorganic semiconductors

Daowei He·Yiming Pan·Haiyan Nan·Shuai Gu·Ziyi Yang·Bing Wu·Xiaoguang Luo·Bingchen Xu·Yuhan Zhang·Yun Li·Zhenhua Ni·Baigeng Wang·Jia Zhu·Yang Chai·Yi Shi·Xinran Wang

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Abstract

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 hybrid 2D heterostructures with p-type dioctylbenzothienobenzothiophene (C8-BTBT) and n-type MoS2. We find that few-layer C8-BTBT molecular crystals can be grown on monolayer MoS2 by vdW epitaxy, with pristine interface and controllable thickness down to monolayer. The operation of the C8-BTBT/MoS2 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 105 at the room temperature. Our devices also exhibit photovoltaic responses with power conversion efficiency of 0.31% and photoresponsivity of 22mA/W. With wide material combinations, such hybrid 2D structures will offer possibilities for opto-electronic devices that are not possible from individual constituents.

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Daowei He, Yiming Pan, Haiyan Nan, Shuai Gu, Ziyi Yang, Bing Wu, Xiaoguang Luo, Bingchen Xu, Yuhan Zhang, Yun Li, Zhenhua Ni, Baigeng Wang, Jia Zhu, Yang Chai, Yi Shi, Xinran Wang. 2015-11-07. A van der Waals pn heterojunction with organic/inorganic semiconductors. https://arxiv.org/abs/1511.02361

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