Experimental Study of the Effect of Interconnects on Phase Noise of K-Band VCO in $0.18\ \mu \mathrm{m}$ CMOS Technology

In this paper, to characterize the effect of interconnects inductance on VCO's phase noise precisely, two K-band VCO circuits that employ DGS as an inductor are designed and analyzed. It's shown that not only the quality factor of the inductor in resonator has a significant effect on VCO's phase noise, the parasitic inductance of the interconnecting transmission lines will also inflect the phase noise severely. To get the Quantitative analysis, a K-band (25 GHz) VCO is implemented in the
$0.18- \mu \mathrm{m}$
1P6M CMOS process and measured.