Analysis of loss mechanisms in coplanar waveguides integrated on bulk CMOS substrates

In mm-wave on-chip applications, integrated transmission lines may have a fundamental role in determining the ultimate performance of the RF blocks of transceivers, due to their rather high losses. A variety of different lines designs on many CMOS processes has already been presented, but a rigorous and systematic investigation on the factors responsible for the final performance of these lines has rarely been shown. In this paper we present a rigorous study of the loss mechanisms occurring in coplanar waveguide transmission lines, which have proved to be the most flexible solution to provide competitive performances even on standard bulk CMOS processes, when a careful optimization of the design is done.