Enhancement of silicon sub-bandgap photodetection by helium-ion implantation

Zhao Wang; Xiaolei Wen; Kai Zou; Yun Meng; Jinwei Zeng; Jian Wang; Huan Hu; Xiaolong Hu

doi:10.1007/s12200-023-00096-x

Enhancement of silicon sub-bandgap photodetection by helium-ion implantation

Front Optoelectron. 2023 Dec 6;16(1):41. doi: 10.1007/s12200-023-00096-x.

Authors

Zhao Wang^{1

2}, Xiaolei Wen³, Kai Zou^{1

2}, Yun Meng^{1

2}, Jinwei Zeng^{4

5}, Jian Wang^{4

5}, Huan Hu^{6

7}, Xiaolong Hu^{8

9

10}

Affiliations

¹ School of Precision Instrument and Optoelectronic Engineering, Tianjin University, Tianjin, 300072, China.
² Key Laboratory of Optoelectronic Information Science and Technology, Ministry of Education, Tianjin, 300072, China.
³ Center for Micro and Nanoscale Research and Fabrication, University of Science and Technology of China, Hefei, 230026, China.
⁴ Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.
⁵ Optics Valley Laboratory, Wuhan, 430074, China.
⁶ ZJUI Institute, International Campus, Zhejiang University, Haining, 311400, China. huanhu@intl.zju.edu.cn.
⁷ State Key Laboratory of Fluidic Power & Mechanical Systems, Zhejiang University, Hangzhou, 310027, China. huanhu@intl.zju.edu.cn.
⁸ School of Precision Instrument and Optoelectronic Engineering, Tianjin University, Tianjin, 300072, China. xiaolonghu@tju.edu.cn.
⁹ Key Laboratory of Optoelectronic Information Science and Technology, Ministry of Education, Tianjin, 300072, China. xiaolonghu@tju.edu.cn.
¹⁰ Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China. xiaolonghu@tju.edu.cn.

Abstract

Silicon sub-bandgap photodetectors can detect light at the infrared telecommunication wavelengths but with relatively weak photo-response. In this work, we demonstrate the enhancement of sub-bandgap photodetection in silicon by helium-ion implantation, without affecting the transparency that is an important beneficial feature of this type of photodetectors. With an implantation dose of 1 × 10¹³ ions/cm², the minimal detectable optical power can be improved from - 33.2 to - 63.1 dBm, or, by 29.9 dB, at the wavelength of 1550 nm, and the photo-response at the same optical power (- 10 dBm) can be enhanced by approximately 18.8 dB. Our work provides a method for strategically modifying the intrinsic trade-off between transparency and strong photo-responses of this type of photodetectors.

Keywords: Helium-ion implantation; Non-invasive photodetection; Silicon photodetector; Sub-bandgap optical absorption.

Publication types

Letter