Silicon Oxycarbide Platform for Integrated Photonics

Abstract—In this article we present silicon oxycarbide (SiOC) as a potential dielectric platform for integrated photonic applications. By controlling the amount of carbon and oxygen in the composition of SiOC films, which in this work are deposited by using a reactive RF magnetron sputtering process, the refractive index of the material can be widely tuned from less than that of silica 1.40 to almost that of silicon carbide (3.0), while keeping high transparency in the near-infrared wavelength range. An in-depth analysis of the structural, morphological and optical properties of the deposited SiOC thin films is reported, pointing out the relationship between the change in the film composition and the tuneability of the refractive index. Single mode optical waveguide with a refractive index contrast of up to 28% and propagation loss as low as 2 dB/cmat 1550 nmare demonstrated. An integrated Mach-Zehnder interferometer is presented as a first example ofPIC realized on high refractive index SiOC platform. Results show that SiOCis a promising alternative to conventional dielectric platforms for the realization of PICs.