Semiconducting nanowires are widely studied as building blocks for electro-optical devices; however, their limited cross-section and hence photo-response hinder the utilization of their full potential. Herein, we present an opto-electronic device for broad spectral detection ranging from the visible (VIS) to the short wavelength infra-red (SWIR) regime, using SiGe nanowires coupled to a broadband plasmonic antenna. The plasmonic amplification is obtained by deposition of a metallic nanotip at the edge of a nanowire utilizing a bottom-up synthesis technique. The metallic nanotip is positioned such that both optical plasmonic modes and electrical detection paths are coupled, resulting in a specific detectivity improvement of ∼1000 compared to conventional SiGe NWs. Detectivity and high gain are also measured in the SWIR regime owing to the special plasmonic response. Furthermore, the temporal response is improved by ∼1000. The fabrication process is simple and scalable, and it relies on low-resolution and facile fabrication steps with minimal requirements for top-down techniques.
Bibliographical noteFunding Information:
AT, ZS, LJL, DNS and RY acknowledge partial funding support from the United States – Israel Binational Science Foundation (grant number 2012088). The LEAP tomograph at NUCAPT was purchased and upgraded with grants from the NSF-MRI (DMR-0420532) and ONR-DURIP (N00014-0400798, N00014-0610539, N00014-0910781, N00014-1712870) programs. NUCAPT received support through the MRSEC program (NSF DMR-1720139) at the Materials Research Center and the SHyNE Resource (NSF ECCS-1542205), NUCAPT from the Initiative for Sustainability and Energy (ISEN), at Northwestern University. GCS thanks DOE grant DE-AC02-06CH11357. AZ would like to acknowledge the support of the Israeli Ministry of Science, Technology and Space.
© The Royal Society of Chemistry.