Metal-Semiconductor-Metal GeSn Photodetectors on Silicon for Short-Wave Infrared Applications
Soumava Ghosh,
Kuan-Chih Lin,
Cheng-Hsun Tsai,
Harshvardhan Kumar,
Qimiao Chen,
Lin Zhang,
Bongkwon Son,
Chuan Seng Tan,
Munho Kim,
Bratati Mukhopadhyay,
Guo-En Chang
Affiliations
Soumava Ghosh
Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-Tech Innovations (AIM-HI), National Chung Cheng University, Chiyai County 62102, Taiwan
Kuan-Chih Lin
Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Chiyai County 62102, Taiwan
Cheng-Hsun Tsai
Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Chiyai County 62102, Taiwan
Harshvardhan Kumar
Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-Tech Innovations (AIM-HI), National Chung Cheng University, Chiyai County 62102, Taiwan
Qimiao Chen
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
Lin Zhang
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
Bongkwon Son
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
Chuan Seng Tan
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
Munho Kim
School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798, Singapore
Bratati Mukhopadhyay
Institute of Radio Physics and Electronics, University of Calcutta, Kolkata 700009, India
Guo-En Chang
Department of Mechanical Engineering, and Advanced Institute of Manufacturing with High-Tech Innovations (AIM-HI), National Chung Cheng University, Chiyai County 62102, Taiwan
Metal-semiconductor-metal photodetectors (MSM PDs) are effective for monolithic integration with other optical components of the photonic circuits because of the planar fabrication technique. In this article, we present the design, growth, and characterization of GeSn MSM PDs that are suitable for photonic integrated circuits. The introduction of 4% Sn in the GeSn active region also reduces the direct bandgap and shows a redshift in the optical responsivity spectra, which can extend up to 1800 nm wavelength, which means it can cover the entire telecommunication bands. The spectral responsivity increases with an increase in bias voltage caused by the high electric field, which enhances the carrier generation rate and the carrier collection efficiency. Therefore, the GeSn MSM PDs can be a suitable device for a wide range of short-wave infrared (SWIR) applications.
