On-chip graded index of refraction optical waveguide and damascene method of fabricating the same

摘要

A graded index of refraction optical waveguide is formed in interlayer dielectric material located above a substrate an integrated circuit-like structure. The waveguide includes a refractive layer of optically transmissive material surrounding a core of optically transmissive material within a trench in the dielectric material. The material of the core has a higher index of refraction than the refractive layer and the material of the refractive layer has a higher index of refraction than the dielectric material. More than one refractive layer may also be formed in the trench, with the inner refractive layer having an index of refraction higher than the outer refractive layer and less than the core.