High-Frequency Behavior of Coupled CMOS Interconnects Built in Different Metallization Layers

In this paper we apply a broadband measurement method to determine the propagation characteristics of coupled-line structures fabricated in different metallization layers of a 0.25 μm CMOS technology. We show that the matrices of frequency-dependent line parameters, as extracted from calibrated four-port S-parameter measurements, agree well with data predicted by numerical calculations, and discuss the impact of metal level height above the substrate on the transmission characteristics.