Buried waveguides written deep inside silicon

摘要

Summary form only given. Silicon waveguides are widely used as optical interconnects and they are particularly important for Si-photonics. Si-based devices, along with other optical elements, are entirely fabricated on the top surface of Si wafers. However, further integration of photonic and electronic devices in the same chip requires a new approach. One alternative is to utilize the bulk of the wafer for fabricating photonic elements. Recently, we reported a direct-laser-writing method that exploits nonlinear interactions and can generate subsurface modifications inside silicon without damaging the surface [1]. Using this method, we fabricated several functional optical elements including gratings [1], lenses [2], and holograms [3]. In this work, we demonstrate optical waveguides entirely embedded in Si.