THz Detection Using +/n-Well Diodes Fabricated in 45-nm CMOS

Electronic-detection up to [Formula Omitted] THz using +/n-well junction diodes in a 45-nm bulk CMOS process is demonstrated. Because the 1/f noise corner frequency is [Formula Omitted] kHz instead of [Formula Omitted] MHz common to Schottky and diode-connected nMOS transistor detectors, despite lower responsivity, detectors using a +/n-well diode with an optimized transit time achieve competitive noise equivalent power (NEP) while exhibiting smaller variations. The junction diode has a measured zero-bias cutoff frequency ([Formula Omitted]) of [Formula Omitted] THz. The direct-antenna matched structure can reach a peak optical responsivity ([Formula Omitted]) of 558 V/W at 0.781 THz with a minimum optical NEP of 56 pW/Hz0.5 at a modulation frequency of 100 kHz.