Gas sensing devices using doped silicon material at mid-infrared region

Mid-infrared (MIR) region is an important region for sensing applications because it contains vibrational resonance for many gases such as methane, carbon monoxide, carbon dioxide, sulfuric acid, ammonia, and acetone. Doped silicon with negative permittivity in MIR region can be used in plasmonic technology to design gas sensors which combining both benefits of silicon and plasmonic technology in MIR region. Fabricating plasmonic integrated devices became easier with current progress in Nanotechnology. Small foot print could be achieved by using Plasmonics technology. Additionally, silicon is CMOS compatible, tunable, and it has high mobility. In this paper we proposed a Fabry-Perot resonator made of doped silicon. Moreover, we studied the response of the Fabry-Perot resonator as a gas sensor in the presence of air, methane and carbon dioxide gases. Consequently, the sensitivity, quality factor and the figure of merit are calculated.