This paper reports a comprehensive study of Si-based GeSn mid-infrared photodetectors, which includes: 1) the demonstration of a set of photoconductors with Sn compositions ranging from 10.5% to 22.3%, showing the cut-off wavelength has been extended to 3.65 um. The measured maximum D* of 1.1x10^10 cmHz^(1/2)W(-1) is comparable to that of commercial extended-InGaAs detectors; 2) the development of surface passivation technique on photodiode based on in-depth analysis of dark current mechanism, effectively reducing the dark current. Moreover, mid-infrared images were obtained using GeSn photodetectors, showing the comparable image quality with that acquired by using commercial PbSe detectors.
@article{arxiv.1906.02848,
title = {Si-based GeSn photodetectors towards mid-infrared imaging applications},
author = {Huong Tran and Thach Pham and Joe Margetis and Yiyin Zhou and Wei Dou and Perry C. Grant and Joshua M. Grant and Sattar Alkabi and Greg Sun and Richard A. Soref and John Tolle and Yong-Hang Zhang and Wei Du and Baohua Li and Mansour Mortazavi and Shui-Qing Yu},
journal= {arXiv preprint arXiv:1906.02848},
year = {2019}
}