Wideband scaleable electrical model for microwave/millimeter wave flip chip interconnects

We present an original method for developing fully scaleable lumped element models for flip chip interconnects. Measurements of test structures and full wave simulations are used to generate circuit models for various single bump configurations. Furthermore, regression models are developed for scaling the values of the elements with the physical attributes of the circuit. The values of L and C in a simple π model have been scaled with the conductor overlap (o) and the distance from the ground bump to the edge of the ground plane (d). It has been found that high overlaps have not only an increased capacitive effect, but an inductive one also and that there is no variation in the lumped element values with d. By incorporating all the factors involved in the flip chip design, the first comprehensive fully scaleable model for microwave flip chip technology is developed based on this approach