Capacitance calculation for a shared-antipad via structure using an integral equation method based on partial capacitance

An integral equation method used for capacitance extraction for axially symmetric geometries is extended in this paper to calculate the via-plane capacitances in shared-antipad via structures, by changing the circular ring cells to arc ones. The proposed method is validated with a commercial finite element method based tool for a typical structure used in modern high-speed printed circuit design.