Three-Dimensional Topological Insulator Bi2Te3/Organic Thin Film Heterojunction Photodetector with Fast and Wideband Response from 450 to 3500 Nanometers

Ming Yang; Jun Wang; Yafei Zhao; Liang He; Chunhui Ji; Xianchao Liu; Hongxi Zhou; Zhiming Wu; Xinran Wang; Yadong Jiang

doi:10.1021/acsnano.8b08056

Three-Dimensional Topological Insulator Bi₂Te₃/Organic Thin Film Heterojunction Photodetector with Fast and Wideband Response from 450 to 3500 Nanometers

ACS Nano. 2019 Jan 22;13(1):755-763. doi: 10.1021/acsnano.8b08056. Epub 2018 Dec 21.

Authors

Ming Yang¹, Jun Wang^{1

2}, Yafei Zhao³, Liang He³, Chunhui Ji¹, Xianchao Liu¹, Hongxi Zhou¹, Zhiming Wu^{1

2}, Xinran Wang³, Yadong Jiang^{1

2}

Affiliations

¹ School of Optoelectronic Science and Engineering , University of Electronic Science and Technology of China , Chengdu 610054 , P.R. China.
² State Key Laboratory of Electronic Thin Films and Integrated Devices , University of Electronic Science and Technology of China , Chengdu 610054 , P.R. China.
³ National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering, and Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , P.R. China.

PMID: 30566317
DOI: 10.1021/acsnano.8b08056

Abstract

In the pursuit of broadband photodetection materials from visible to mid-IR region, the fresh three-dimensional topological insulators (3D TIs) are theoretically predicted to be a promising candidate due to its Dirac-like stable surface state and high absorption rate. In this work, a self-powered inorganic/organic heterojunction photodetector based on n-type 3D TIs Bi₂Te₃ combined with p-type pentacene thin film was designed and fabricated. Surprisingly, it was found that the Bi₂Te₃/pentacene heterojunction photodetector exhibited a fast and wideband response from 450 to 3500 nm. The optimized responsivity of photodetector reached 14.89 A/W, along with the fast response time of 1.89 ms and the ultrahigh external quantum efficiency of 2840%. Moreover, at the mid-IR 3500 nm, our devices demonstrated a responsivity of 1.55 AW^-1, which was several orders of magnitude higher than that of previous 3D TIs photodetector. These excellent properties indicate that the inorganic/organic heterojunction, that is, the combination of 3D TIs with organic materials, is an exciting structure for high performance photodetectors in the wideband detection region. On account of the fact that the device is constructed on mica substrate, this work also represents a potential scenario for flexible optoelectronic devices.

Keywords: Bi2Te3 thin films; fast response; flexible; inorganic/organic heterojunction; self-powered; wideband photodetector.