Broadband photodetector based on SnTe nanofilm/n-Ge heterostructure

Liyuan Song; Libin Tang; Qun Hao; Kar Seng Teng; Hao Lv; Jingyu Wang; Jiangmin Feng; Yan Zhou; Wenjin He; Wei Wang

doi:10.1088/1361-6528/ac80cc

Broadband photodetector based on SnTe nanofilm/n-Ge heterostructure

Nanotechnology. 2022 Jul 29;33(42). doi: 10.1088/1361-6528/ac80cc.

Authors

Liyuan Song^{1

2

3}, Libin Tang^{1

2

3}, Qun Hao¹, Kar Seng Teng⁴, Hao Lv², Jingyu Wang², Jiangmin Feng², Yan Zhou², Wenjin He², Wei Wang²

Affiliations

¹ The Laboratory of Photonics Information Technology, Ministry of Industry and Information Technology, School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
² Kunming Institute of Physics, Kunming 650223, People's Republic of China.
³ Yunnan Key Laboratory of Advanced Photoelectronic Materials & Devices, Kunming 650223, People's Republic of China.
⁴ Department of Electronic and Electrical Engineering, Swansea University, Bay Campus, Fabian Way, Swansea SA1 8EN, United Kingdom.

PMID: 35830829
DOI: 10.1088/1361-6528/ac80cc

Abstract

Combining novel two-dimensional materials with traditional semiconductors to form heterostructures for photoelectric detection have attracted great attention due to their excellent photoelectric properties. In this study, we reported the formation of a heterostructure comprising of tin telluride (SnTe) and germanium (Ge) by a simple and efficient one-step magnetron sputtering technique. A photodetector was fabricated by sputtering a nanofilm of SnTe on to a pre-masked n-Ge substrate.J-Vmeasurements obtained from the SnTe/n-Ge photodetector demonstrated diode and photovoltaic characteristics in the visible to near-infrared (NIR) band (i.e. 400-2050 nm). Under NIR illumination at 850 nm with an optical power density of 13.81 mW cm^-2, the SnTe/n-Ge photodetector exhibited a small open-circuit voltage of 0.05 V. It also attained a high responsivity (R) and detectivity (D*) of 617.34 mA W^-1(at bias voltage of -0.5 V) and 2.33 × 10¹¹cmHz^1/2W^-1(at zero bias), respectively. Therefore, SnTe nanofilm/n-Ge heterostructure is highly suitable for used as low-power broadband photodetector due to its excellent performances and simple device configuration.

Keywords: Ge; SnTe; heterostructure; photodetector.