New formulas of interconnect capacitances based on results of conformal mapping method

The work presents new formulas for the capacitances of the most common two-dimensional (2-D) interconnect structures. The results have been obtained by using a physically-based approach: each geometry has been divided into elementary components studied rigorously with the conformal mapping method. The capacitances of structures composed by one, two, or three lines on a ground plane are then written as a weighted sum of such elements. Since the elementary terms already account for the correct geometrical dependencies, very few numerical simulations have been required to tailor the formulas, attaining an accuracy higher than previously known results, over a wide range of the geometrical parameters of the lines.