Fast Computational Model for Electrical Characterization of Complex 3D-packaging

With the relentless scaling down of the modern semiconductor devices, the size of the transistors is approaching to nano-scale while the clock frequency is operating at multi- gigahertz regime(1). This shall compel the system integration towards to be 3D packaging tech- nology, which achieves a high integration and miniaturization. The high density integration will result in the high power density, signal rise time and power supply voltage decreasing, the fast signal rise will induce the switching noise at the power distribution network(PDN). These switch- ing noise leads to the unwanted efiects such as the ground bounce, power supply compression and electromagnetic interference on the power distribution network, which must be designed out during the design stage. In general, a high integrated package is constructed with multilayer of power/ground planes and signal planes with hundreds or thousand of high-density vias. The signal will pass through number of layers with difierent structures like microstrip lines, vias and bumps. Due to the impedance difierence between the via and signal traces, it will deteriorate the signal integrity and cause the EMI problems. To minimize the noise level and enhance the signal integrity, it necessities to analyze the entire package electrical performance at the package design stage. But, due to the complexity of the package and board conflguration, it is not possible to deal with the entire problem based on the conventional electromagnetic computation techniques such as FEM, FDTD and MOM. Hence, a fast yet accurate electromagnetic simulation method is required. In this paper, we shall present a novel semi-analytical method which couples with the integral equation (named as 2.5D method). This coupled 2.5D method is then accelerated by the fast algorithm to model the electrical performance of the complex package problems. The formulation and simulation results shall be presented.