Characterization of Light propagation loss in Photonics devices using High-Resolution CDSEM metrology

Abstract

Photonic devices manufactured on core materials (by example Si or SiN) wafers, using a semiconductor fabrication technique, was demonstrated to increase data transmission speed, consume less power, and generate less heat than conventional electronic circuits. Light propagation loss strongly dependents on the Waveguide edge roughness. To reduce roughness, three patterning methods are evaluated, dry vs wet lithography, OPC (Optical proximity correction) and Hydrogen anneal on two types of waveguides, RIB and STRIP, fabricated on SOI wafer. In this paper, we demonstrate innovative methods to measure edge roughness of straight and curved WGs with a CDSEM. CD roughness measurements are correlated with light propagation loss.