Accurately extracting silicon waveguide dimensions from a single high-order Mach-Zehnder Interferometer

Abstract

We experimentally demonstrate a new methodology for the extraction of dimensions from silicon-on-insulator (SOI) strip waveguides manufactured in IMEC’s iSiPP50G silicon photonics platform. The effective index (neff) and group index (ng) of the waveguide are determined from the spectral data of a single high-order Mach-Zehnder Interferometer (MZI). In this study, we introduce an innovative mapping model that effectively relates the geometric dimensions of the SOI waveguide to its neff and ng, thereby enhancing mapping accuracy and reducing model complexity. Furthermore, we will elucidate the feasibility and constraints for extracting neff and ng through the optical transmission measurement of only a single high-order MZI. Our analysis also addresses the parameter extraction errors that have a significant impact on the results, which have not been previously discussed in the literature.