Characterization of On-die Interconnects Exhibiting Slow-Wave Propagation

This paper presents the characterization of on-die interconnects fabricated on SOI technology exhibiting slow-wave propagation. The characterization relies on building a frequency dependent transmission line model from two measured lines of different lengths. The measured S-parameters and TDR data are found to exhibit behaviors unlike those typically observed in PCB interconnects. The odd behaviors are due to the so-called slow-wave mode of propagation. This effect occurs below 1 GHz and manifests itself by very large losses in the stack-up and a low propagation velocity. The frequency dependent model and the measurements are found to correlate well in frequency and time-domains.