Experimental via characterization for the signal integrity verification of discontinuous interconnect line

Interconnect lines with inter-layer vias are experimentally characterized by using high-frequency S-parameter measurements. Test patterns are designed and fabricated using a package process and measured using Vector Network Analyzer (VNA) up to 25 GHz. Then, by modeling a via as a circuit, its model parameters are determined. It is shown that the circuit model has excellent agreement with the measured S-parameters. The circuit performance of the lines with inter-layer vias is evaluated by using the developed circuit model. Thereby, it is shown that via may have a substantially deteriorative effect on the signal integrity of high-speed integrated circuits.