Response Optimization of Antenna-Coupled FET Detectors for 0.85-to-1-THz Imaging

This letter presents several configurations of terahertz (THz) pixel structures with different bow-tie antennas and field-effect transistor (FET)-based detectors, implemented in a 0.15-μm standard CMOS technology, operating at a radiation frequency range of 0.85-1 THz for CMOS imaging applications. The innovative FET detector structures are investigated for higher power coupling efficiency with the integrated antennas, aiming to improve the THz detection behavior in terms of responsivity and noise equivalent power. Experimental THz characterization of the fabricated structures provides the guidelines for the future implementation of THz imaging arrays. Images of concealed metallic objects are acquired in a single-pixel mode under continuous THz illumination.