OPTICAL WAVEGUIDE STRUCTURE WITH WAVEGUIDE COUPLER TO FACILITATE OFF-CHIP COUPLING

摘要

Aspects of the invention are directed to a method for forming an optical waveguide structure. Initially, a base film stack is received with an optical waveguide feature covered by a lower dielectric layer. An etch stop feature is then formed on the lower dielectric layer, and an upper dielectric layer is formed over the etch stop feature. Subsequently, a trench is patterned in the upper dielectric layer and the etch stop feature at least in part by utilizing the etch stop feature as an etch stop. Lastly, a waveguide coupler feature is formed in the trench, at least a portion of the waveguide coupler feature having a refractive index higher than the lower dielectric layer and the upper dielectric layer. The waveguide coupler feature is positioned over at least a portion of the optical waveguide feature but is separated from the optical waveguide feature by a portion of the lower dielectric layer.

主权项

1. A film stack comprising:
an optical waveguide feature; a lower dielectric layer covering the optical waveguide feature; a waveguide coupler feature disposed over at least a portion of the optical waveguide feature but separated from the optical waveguide feature by a portion of the lower dielectric layer; and an upper dielectric layer flanking at least a portion of the waveguide coupler feature; wherein the waveguide coupler feature is characterized by a refractive index higher than the lower dielectric layer and the upper dielectric layer.