Broadband 0.4-4 THz Generation in 90nm SiGe BiCMOS

This paper presents a silicon-based source that can radiate power beyond 1 THz. A PIN diode frequency multiplier is driven by a Colpitts oscillator designed at a fundamental frequency of 130 GHz. The PIN diode exhibits a sharp reverse recovery, which can be exploited for strong harmonic generation in THz band. Wireless injection locking is also demonstrated to lock the chip to an external source and reduce phase noise. The design is implemented in GlobalFoundries 90 nm SiGe BiCMOS process and has an effective isotropic radiated power (EIRP) of 13 dBm and a 6% tuning range at 390 GHz. Fourier-transform infrared (FTIR) spectroscopy with a room temperature deuterated triglycine sulfate (DTGS) detector is used to measure the radiated power. Measurement results confirm the presence of tones well beyond 1 THz, with an SNR of 13.7, 8.9, 4.9, and 3.1 dB at 1.17, 2.21, 3.25, and 4.03 THz, respectively.