A Monolithic On-chip 15 GHz Phase-Shifter

This paper presents a monolithic on-chip phase-shifter designed to work at 15 GHz on a p-type silicon substrate. Using a simple process with only two photolithography masks, the active elements are some $\mathrm{N}^{+} \mathrm{P P}^{+}$junctions integrated in the substrate and optimized at the same time as the transmission lines with a co-design approach. These junctions allow to commute the signal transmission between two paths and the difference in the paths length offers a phase difference which can be chosen depending on the application. In the proposed demonstrator, the measured phase difference is 160°.