Low phase noise SiGe push-push oscillators for cm- and mm-wave applications

In this paper, we present several monolithically integrated push-push oscillators in the frequency range from 47 GHz to 190 GHz. The MMICs are fabricated in a production near SiGe:C bipolar technology developed by Infineon Technologies AG. The transistors show a maximum transit frequency of f_T = 200 GHz and a maximum frequency of oscillation f_max = 275 GHz. The passive circuitry is realized using integrated transmission-line components, integrated spiral inductors, MIM-capacitors and TaN resistors. The frequency of the output signal of the oscillators can be tuned either by varying the bias voltage of the whole oscillator circuit or using the capacitance variation of a base collector junction as a tuning varactor. Some of the oscillators show excellent phase noise behavior, especially the 190 GHz oscillator gives a world record in output power and phase noise for HBT-oscillators.