Phase Change Material Based Phase Trimming for Integrated Photonics

Silicon-on-insulator (SOI) is a preferred platform for fabricating photonic integrated circuits (PICs) due to its favorable properties. However, the high refractive index contrast in SOI waveguides makes silicon photonic circuits highly susceptible to fabrication imperfections, where even minor variations in waveguide dimensions can induce significant phase errors. These phase errors are particularly critical in applications such as waveguide optical gyroscopes, where precise phase control is essential for accurate sensing. To address this challenge, RMD Inc. is developing and evaluating the design, fabrication, and manufacturability of PICs featuring chalcogenide phase-change material (PCM)-integrated waveguides for phase trimming. These PCM-based trimmers will operate within the 700-900 nm spectral range, achieving a low insertion loss of < 0.02 dB per p phase shift and enabling a full 2p optical phase shift.