The effect of edge metal profiles on the accuracy of electrical modeling of advanced packages

Electronic package edge metal profiles have an effect on package characteristics on an order increasingly close to the tolerances expected for the package electrical performance. Several two-dimensional (2-D) tools are available that can be used to evaluate predesign and layout issues with nonrectangular edge profiles. However, tools that extract models from actual designs using the most up-to-date computer-aided design/computer-aided engineering (CAD/CAE) design and modeling flows do not yet take into account these real-world metal geometries. Variations in impedance and crosstalk associated with real profiles versus rectangular idealizations are identified for some typical cases and a computational procedure is discussed which may efficiently address this problem.