Layout Optimization of Short De-embedding Structure for Accurate On-Chip Inductor Characterization

A potentially significant limitation of typical short structure in de-embedding launch line inductance with ground-signal-ground (GSG) padsets is revealed in this paper. It is shown that the calculated inductance (L) value with conventional open-short-pad (OSP) de-embedding is significantly higher than the actual value. With the help of electro-magnetic (EM) simulations, the mechanism behind this inaccurate short de-embedding for L calculation is demonstrated. A simple alternative short structure is proposed to alleviate this issue. The proposed structure is extensively validated using well calibrated EM simulations across inductor geometries. Finally, measured result of spiral inductor with GSG padsets validate the merit of the proposed approach.