New algorithm for interconnect capacitance extraction based on a fictitious domain method

We propose a new approach for fast and accurate extraction of capacitance in multiconductor cells embedded in multiple dielectric media. We use the so-called fictitious domain method with Lagrange multipliers for the problem formulation. It leads to a coupled linear system which unknowns are the potential on a regular 3D grid of a simple-shaped domain, imbedding the dielectric media, and the charge on a mesh of the conductor surfaces. Thanks to the regular grid, the storage of information related to the volumic mesh is not necessary and we can use fast solvers. Numerical results on 3D complex structures show that the method is more efficient, both in time and memory, than a finite elements or a boundary elements method.