Quasi optical THz detectors in Si CMOS

Abstract

We report on design and implementation of narrowband and broadband field-effect transistor-based detectors for THz frequency range (TeraFETs) using commercial CMOS fabrication process. Exploiting the plasma wave mixing principle, which becomes important above the transistor's cut-off frequency, we achieve highly sensitive detection at room temperature operation conditions. At 297 GHz, the resonant detector demonstrates optical noise-equivalent power (NEP) including all losses of 31 pW per square root of Hz. For the same conditions, broadband device exhibits NEP below 100 pW per square root of Hz in a frequency range from 500 GHz to 750 GHz. The optical, antenna effective area-limited NEP of resonant device at 620 GHz is below 10 pW per square root of Hz. These performance values are competitive with the best commercially available room temperature THz detectors.