US Patent 11686906 Self-aligned structure and method on interposer-based PIC

Alignment aid structures and the method of formation of these structures on an interposer comprised of a planar waveguide layer and a base structure, facilitate the alignment of the optical axes of optical and optoelectrical devices formed from and mounted to the interposer. Alignment aids formed from a common hard mask on the planar waveguide layer of the interposer structure include vertical and lateral alignment structures and fiducials. Optical losses for signals propagating in interposer-based photonic integrated circuits are reduced with effective alignment structures and methods.