Multi-port measurement-based package model extraction for single-ended and differential signaling

This paper presents a hybrid method that combines multi-port measurements, electromagnetic (EM) numerical tools, and extrapolation techniques for accurate characterization and modeling of an entire chip-to-chip interconnection link over tens of gigahertz (GHz) ranges. To characterize multi-line transmission lines, a frequency-dependent RLGC model was found from two-port and four-port measured scattering (S) parameters, and then the tabular W-element models were generalized for N-port models using a numerical electromagnetic (EM) field solver. As for the 3D structures, such as package vias and sockets, high-frequency test structures and fixtures were designed to obtain two-and four-port S-parameters. Again, two- and four-port limited measurement-based model were generalized to N-port three-dimensional problems using an EM tool. An entire chip-to-chip link consisting of 20-port was then generated and modeled using measurement data or measurement-based models after enforcing a certain passivity condition. Using the model, 10Gbps performances were successfully predicted for a generic chip-to-chip interconnection including only passive devices such as a CPU package, a socket, a PCB MB trace, and chipset package.