Patent ID: 11862650
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. An image sensor, comprising:
a plurality of photodetectors disposed in a semiconductor substrate;
a light filter grid structure disposed over a back-side of the semiconductor substrate;
a light filter disposed in the light filter grid structure;
a dielectric layer disposed over the back-side of the semiconductor substrate and vertically between the plurality of photodetectors and the light filter; and
a plurality of noise reducing structures disposed vertically between the light filter and the back-side of the semiconductor substrate, wherein the plurality of noise reducing structures overlie the plurality of photodetectors, respectively, and wherein the plurality of noise reducing structures have a higher refractive index than the dielectric layer,
wherein
a first group of photodetectors of the plurality of photodetectors are disposed in a central region of the image sensor and a second group of photodetectors of the plurality of photodetectors are disposed in a peripheral region of the image sensor;
a first group of noise reducing structures of the plurality of noise reducing structures are disposed in the central region of the image sensor and a second group of noise reducing structures of the plurality of noise reducing structures are disposed in the peripheral region of the image sensor; and
the second group of noise reducing structures are shifted toward the central region of the image sensor in relation to the second group of photodetectors.