Enhanced performance of AlGaN/GaN HEMT-Based THz detectors at room temperature and at low temperature

We present optimized THz detectors based on AlGaN/GaN field-effect transistors with integrated broadband bow-tie antennas (bow-tie TeraFETs). Designed with a comprehensive circuit model and fabricated with a recently developed AlGaN/GaN MMIC process, the devices reach a performance at room temperature which hitherto has only been achieved with Si CMOS TeraFETs. Capable of broadband detection from 0.2 to at least 1.2 THz, they exhibit a remarkable optical NEP of 25.4 pW/√Hz at 500 GHz. For further refinement of the device model including thermoelectric contributions and the extraction of temperature-dependent physical parameters, we extend device characterization to cryogenic temperatures.