边界元法在数模混合集成电路衬底耦合参数提取中的应用

Boundary Element Method for Extraction Substrate Coupling Parameter in Mixed\|Signal ICs

把边界元方法运用到数模混合集成电路衬底耦合电阻参数的提取 .求出了满足衬底边界条件的格林函数 ,而不是采用三维自由空间的格林函数 ,从而使需离散的边界仅仅是衬底表面的端口区 .在计算阻抗元素时 ,利用基于快速富立叶变换 ( FFT)的离散余弦变换 ( DCT)使计算速度大大提高 .和有限差分法相比 ,精度差不多而计算速度提高一个数量级以上 .

Boundary Element Method(BEM) is used in substrate coupling parameter extraction of mixed\|signal ICs. Green Function that satisfies the substrate boundary conditions is solved out in this paper. Using this Green Function instead of the Green Function in free space makes only the ports area on the substrate top surface need to be discretized. Discrete Cosine Transform which is based on FFT is used when determine impedance element, which improves the solution speed dramatically. Comparing to Finite Difference Method, the solution speed is improved by one order of magnitude, but the accuracy is kept. Comparing to Wemple's result where Voronoi tessellation is used to partition the layout and analytical method is used to compute substrate coupling, the accuracy of BEM is improved significantly.