Accurate Q prediction for RFIC spiral inductors using planar EM solvers

In this work, we show how to estimate the Q of a spiral inductor using a planar electromagnetic (EM) simulator based on integral equation technique and the Method-of-Moments. The method´s main advantage is that a 3D EM simulator that calculated electromagnetic field inside non-perfect metal shapes is not needed. Rather, a planar simulator combined with available cross-sectional transmission line models can be used to obtain a useful estimate of the Q. The method gives agreement with experimental results to a few percent, as opposed to much larger errors with conventional planar solvers, or unrealistic run times with 3D simulators when meshing of the interior of the conductors is used.