A 250-300 GHz Frequency Multiplier-by-8 Chain in SiGe Technology

This paper presents a fully-differential wideband and low power multiplier-by-8 chain covering the frequency band from 250 to 300 GHz, fabricated in a newly developed 130 nm SiGe:C BiCMOS technology from IHP featuring f(t) / f(max) of about 470 / 650 GHz. The fully differential multiplier chain consists of a Gilbert cell based frequency quadrupler followed by an amplifier and a frequency doubler. Broadband passive baluns are used both in input and in output for enabling single-ended measurements. The designed circuit achieves a measured 3 dB bandwidth of 50 GHz (18 %). The peak saturated output power is -5 dBm and the overall power consumption is 125 mW, for a drain efficiency of 0.25 %, occupying a silicon area of 0.4 mm(2).