Low phase noise CMOS distributed oscillators using MEMS low loss transmission lines

For the first time, low noise distributed oscillators for millimeter wave signal generation have been realized by using fully IC compatible, monolithically-integrable 3-D RF MEMS transmission lines. The active core circuits of the distributed oscillators have been fabricated using 0.18 μm CMOS processes. On the top of this CMOS circuits, low-loss MEMS transmission lines have been monolithically integrated suspending by 25 μm. Phase noise of the fabricated MEMS distributed oscillators has been measured as -125.7 dBc/Hz at 1 MHz offset frequency from oscillation frequency of 13 GHz. This is the lowest phase noise ever reported on distributed oscillators implemented in CMOS technology.