Patent ID: 8625941

Claim:
A device having a reflective grating structure, comprising: a substrate; a bottom clad layer on the substrate; a waveguide core layer on the bottom clad layer; a top clad layer on the waveguide core layer; at least one metal grating structure disposed adjacent to an interface between the waveguide core layer and one of the bottom clad layer and the top clad layer, the at least one metal grating structure configured to reflect at least a portion of an incident electromagnetic (EM) radiation coupled into the waveguide core layer; and a reflective layer spaced apart from the waveguide core layer such that one of the bottom clad layer and the top clad layer is disposed between the reflective layer and the waveguide core layer, the reflective layer configured to cause an uncoupled portion of an EM radiation traveling away from the waveguide core layer to reflect back toward the waveguide core layer, wherein a material of the at least one metal grating is different from a material of the bottom clad layer; and wherein a material of the at least one metal grating is different from a material of the top clad layer.