A novel structure of non-planar RF spiral inductor based on silicon

In this paper, a novel structure of non-planar inductor based on silicon is presented. The simulation plot of the magnetic distribution reveals that magnetic field reaches its maximum intensity near the inner turns of planar inductor, so it is necessary to deal with the peak value of the magnetic field in the centre of the inductor which causes great substrate loss. An extra layer of silicon dioxide under central several turns of the inductor is proposed in this novel design, and then the inductor becomes non-planar. The simulation results show this method can increase the peak Q factor by nearly 10%