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arXiv · 1906.02848

Si-based GeSn photodetectors towards mid-infrared imaging applications

Huong Tran·Thach Pham·Joe Margetis·Yiyin Zhou·Wei Dou·Perry C. Grant·Joshua M. Grant·Sattar Alkabi·Greg Sun·Richard A. Soref·John Tolle·Yong-Hang Zhang·Wei Du·Baohua Li·Mansour Mortazavi·Shui-Qing Yu
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Abstract

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.

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Huong Tran, Thach Pham, Joe Margetis, Yiyin Zhou, Wei Dou, Perry C. Grant, Joshua M. Grant, Sattar Alkabi, Greg Sun, Richard A. Soref, John Tolle, Yong-Hang Zhang, Wei Du, Baohua Li, Mansour Mortazavi, Shui-Qing Yu. 2019-06-07. Si-based GeSn photodetectors towards mid-infrared imaging applications. https://arxiv.org/abs/1906.02848

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