Millimeter-wave VCO using striped inductor

Millimeter wave striped inductor VCO has been studied. To obtain lower phase noise, the enhancement of Q-factor of inductor is essential, although it is difficult in the case of dozens gigahertz region due to skin effect. In our previous results, quasi-millimeter wave striped inductor VCO can be obtained lower phase noise by suppression of skin effect. In this work, we have been investigated corner frequency of striped inductors and the phase noise of several oscillation frequencies VCO with striped inductor. The corner frequency of striped inductor achieves approximately two times higher than that of conventional inductor. The minimum phase noise of several types of striped inductor VCOs show −106, −102, and −97 dBc/Hz at 1-MHz offset from fosc = 23, 25, and 40 GHz, respectively. It exhibits 2–4 dB better phase noise compare than conventional inductor VCO. The process technology using all experiments is 65-nm standard CMOS with thick Cu metal.