High-Frequency-Measurement-Based Circuit Modeling and Power/Ground Integrity Evaluation of Integrated Circuit Packages

Abstract

The frequency-variant characteristics of a pair of package power and ground net are experimentally investigated and modeled by using frequency-variant grid-type equivalent circuits, where each cell of the grid is modeled with vertically stacked RLC-ladder circuits. Various test patterns are designed and fabricated by employing a ball grid array (BGA) package process. Then the test patterns are characterized by using impedance analyzer, time domain reflectometry and time domain transmission (TDR/TDT), and vector network analyzer (VNA). Based on the experimental characterizations, not only are material constants and circuit model parameters determined, but also the conductor roughness and other frequency-variant effects are modeled. It is shown that the SPICE-based circuit simulation using the proposed circuit model has an excellent agreement with the measurement data in the range of 100 MHz similar to 15 GHz. Then, it is also shown that the various types of package performance evaluations can be very efficiently as well as accurately achieved with the proposed technique.