10GHz Varactor-less VCO with Helium-3 Ion Irradiated Inductor

This paper presents a 10GHz varactor-less voltage-controlled oscillator (VCO) with helium-3 ion irradiated inductor. The purpose of this paper is to recover VCO tank quality factor at high frequency due to the degradation of varactor and inductor. The proposed VCO adopts variable supply method to tune the resonant frequency instead of using a standalone varactor. The helium-3 ion irradiation is applied to further improve inductor quality factor by reducing substrate loss. The VCO has been implemented in a standard 180nm CMOS process for validation. It achieves phase noise of −139.5dBc/Hz at 10MHz offset frequency with 10mW power consumption, which is comparable with other state-of-the art VCOs implemented in more advanced process.