New simulation methodology of 3D surface roughness loss for interconnects modeling

As clock frequencies exceed giga-Hertz, the extra power loss due to conductor surface roughness in interconnects and packagings is more evident and thus demands a proper accounting for accurate prediction of signal integrity and energy consumption. Existing techniques based on analytical approximation often suffer from a narrow valid range, i.e., small or large limit of roughness. In this paper, we propose a new simulation methodology for surface roughness loss that is applicable to general surface roughness and a wide frequency range. The method is based on 3D statistical modeling of surface roughness and the numerical solution of scalar wave modeling (SWM) with the method of moments (MOM). The spectral stochastic collocation method (SSCM) is applied in association of random surface modeling to avoid the time-consuming Monte-Carlo (MC) simulation. Comparisons with existing methods in their respective valid region then verify the effectiveness of our approach.