Mid- to far-infrared localized surface plasmon resonance in chalcogen-hyperdoped Si

Mid-infrared plasmonic sensing allows the direct targeting of molecules relevance in the so-called “vibrational fingerprint region”. Presently, heavily doped semiconductors exhibiting the potential to replace and outperform metals in the mid- infrared frequency range to revolutionize plasmonic devices. In this work, we demonstrate the occurrence of localized surface plasmon resonances (LSPR) in Te heavily-doped Si layers developed by ion implantation combined with flash lamp annealing. We fabricate micrometer-sized antennas out of the Te-hyperdoped Si layers by electron-beam lithography and reactive ion etching processes. The optical response characterized by Fourier-transform infrared (FTIR) spectroscopy demonstrates the enhancement of localized plasmon resonances in antennas, from mid- to far- infrared frequency range. Our results set a new path toward integration of plasmonic sensors with the one-chip CMOS platform.