Patent ID: 9103972
Filing Date: 2015-08-11
Classification: G02B

Abstract:
1. A method for forming an optical waveguide structure, the method comprising the steps of: receiving a base film stack with an optical waveguide feature covered by a lower dielectric layer; forming an etch stop feature on the lower dielectric layer; forming an upper dielectric layer over the etch stop feature; patterning a trench in the upper dielectric layer and the etch stop feature at least in part by utilizing the etch stop feature as an etch stop; and forming a waveguide coupler feature 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; wherein 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.