A 0.65 THz Focal-Plane Array in a Quarter-Micron CMOS Process Technology

A focal-plane array (FPA) for room-temperature detection of 0.65-THz radiation has been fully integrated in a low-cost 0.25$ mu$m CMOS process technology. The circuit architecture is based on the principle of distributed resistive self-mixing and facilitates broadband direct detection well beyond the cutoff frequency of the technology. The 3 $,times,$5 pixel array consists of differential on-chip patch antennas, NMOS direct detectors, and integrated 43-dB voltage amplifiers. At 0.65 THz the FPA achieves a responsivity $(R_v)$ of 80 kV/W and a noise equivalent power (NEP) of 300 pW/ $sqrt{hbox{Hz}}$. Active multi-pixel imaging of postal envelopes demonstrates the FPAs potential for future cost-effective terahertz imaging solutions.