A FDTD method for fast simulation of decoupling capacitors on multilayer multichip modules

We present a new method for the simulation of the power supply system on multilayer substrates of multichip modules (MCM). In particular we investigate the efficiency of extended high capacitance layers used as decoupling capacitors. The proposed method works with a lumped element FDTD technique which facilitates electromagnetic simulation of the substrate simultaneous with simulation of the mounted electronic circuit. The stratified configuration of multilayer structures allows division of the 3D problem into separate 2D problems. This yields an efficient algorithm. The algorithm has been implemented in C++ and tested with different examples. Furthermore we present reference data derived by analytical investigation of a circular plate capacitor. This data is used to evaluate the simulation results.