Monolithic Integration of Air-Clad Optical Through-Silicon Waveguides in Silicon (TH Wildau et al.)

Researchers from various universities and institutes have published a technical paper on the monolithic integration of air-clad optical through-silicon waveguides in silicon for 3D chip-to-chip photonic interconnects. The study focuses on the fabrication of these waveguides using Bosch and cryogenic deep reactive-ion etching, evaluating different designs with varying core sizes and propagation lengths. The results show that cryogenic-etched rib waveguides achieve higher transmission rates compared to Bosch-etched ribs. The technology offers a scalable pathway for 3D photonic interconnects in a complementary metal-oxide semiconductor-compatible manner.