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

Claim 18:
19. A coupling system comprising:
an optical fiber configured to carry an optical signal; and
a chip in optical communication with the optical fiber, wherein the chip comprises:
a substrate;
a grating on a first side of the substrate, wherein the grating is configured to receive the optical signal;
an interconnect structure over the grating on the first side of the substrate, wherein the interconnect structure defines a cavity aligned with the grating; and
a first polysilicon layer on a second side of the substrate, wherein the second side of the substrate is opposite to the first side of the substrate; and
a second polysilicon layer on the first side of the substrate, wherein a maximum thickness of the first polysilicon layer is equal to a maximum thickness of the second polysilicon layer.