| A design of experiments method for the first comprehensive RF and microwave flip-chip design rule development is proposed. First, the factors involved in the design process are identified. These include the type of transmission line launch used, the material chosen, the bump geometry and placement, the use of multiple bumps, the effect of underfill, as well as compensation techniques such as bump misalignment and use of transmission line sections. The parasitic effects of these factors are included in a fully scaleable lumped element model of the bump transition that can be easily implemented in simulation during the system design process. The quantification of the effects of the factors involved and the prediction of the behavior of the interconnection in the intervals defined for each factor are done using a design of experiments (DOE) approach. Input variables are established for each experiment and analysis intervals are defined; then the outputs are obtained using high-order computational methods, electromagnetic (EM) field simulation, circuit simulation and measurements of test structures. The results are summarized in a design rule set for the specific fabrication process similar to RF integrated circuits (RFIC) design rules. |
