Patent ID: 11892681
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. A coupling system comprising:
an optical fiber configured to carry an optical signal;
a substrate;
a waveguide layer on a first side of the substrate;
a grating optically connected to the waveguide layer, wherein the grating is configured to receive the optical signal;
an interconnect structure on the first side of the substrate, wherein the waveguide layer is between the interconnect structure and the substrate, and the interconnect structure defines a cavity aligned with the grating;
a first polysilicon layer over the grating on the first side of the substrate; and
a second polysilicon layer on a second side of the substrate, wherein a maximum thickness of the first polysilicon layer is equal to a maximum thickness of the second polysilicon layer.