A Monolithically Integrated InP HBT-based THz Detector

THz power detection beyond 100 GHz still faces challenges in sensitivity, speed, and the capability of detector arrays. This paper introduces the first measurement outcomes of InP heterojunction bipolar transistor (HBT) THz detectors featuring monolithically integrated antenna structures. These detectors exhibit high sensitivity, rapid response times, and scalability for large arrays, leveraging self-mixing effects. Achieving high sensitivity necessitates tailored adaptation of InP HBT devices to broadband on-chip antennas. Sensitivities surpassing 100mA/W are attained between 100 GHz and 500 GHz, with values exceeding 300mA/W for frequencies below 200 GHz. Notably, lens and substrate losses are not factored into this sensitivity. Expectations are high for sensitivity values to surpass those achieved with FETs in the same frequency range, further establishing the superiority of this approach in THz power detection.