Nanometric CMOS-SOI-NEMS Transistor for Uncooled THz Sensing

This paper reports the design (electrical, mechanical, and thermal), fabrication technology by post-complementary metal–oxide–semiconductor (CMOS) nano- machining, and characterization of CMOS-silicon on insulator (SOI)-nanoelectromechanical systems (NEMS) transistors fabricated in 180-nm technology. The thermally isolated, nanomachined CMOS-SOI-NEMS transistor reported here is designed for monolithic uncooled passive terahertz sensing and is dubbed “TeraMOS,” while the fabrication technology is dubbed “CMOST.” With responsivity of ${\sim}0.5~{\rm A}/{\rm W}$ , noise equivalent power (NEP) of the order of NEP/ $\surd {\rm Hz}\vert _{1,{\rm Hz}}=7.8~{\rm pW}/\surd {\rm Hz}$ , ${\rm D}^{\ast }$ of $0.34\cdot 10^{10}~{\rm cm}\surd {\rm Hz}/{\rm Wa\tt}$ , and evaluated noise equivalent temperature difference of ${\sim}{\rm 1.25}~{\rm K}$ , this uncooled THz sensor in standard CMOS-SOI technology may enable monolithic uncooled passive THz imagers.