Patent ID: 9299740
Filing Date: 2016-03-29
CPC Classification: H01L

Claim Text:
1. A method comprising: providing a device wafer having a conductive feature formed at a back-side of the device wafer and having a photo diode formed at a front-side of the device wafer; forming a dielectric layer at the front-side of the device wafer, wherein the dielectric layer comprises one or more metallization layers formed therein, and wherein the photo diode is located between the dielectric layer and the back-side of the device wafer in a thickness direction of the device wafer; lining the back-side of the device wafer and the conductive feature with a passivation layer, the passivation layer physically contacting the back-side of the device wafer; forming a grid film over the passivation layer, wherein the grid film comprises a first portion over the conductive feature and a second portion over the photo diode, and wherein a top surface of the first portion of the grid film and a top surface of the second portion of the grid film are at different levels; reducing the first portion of the grid film; patterning the second portion of the grid film to form a grid pattern over the photo diode, the grid pattern exposing portions of the passivation layer; and forming a color filter in the grid pattern and over the photo-diode, wherein no portion of the color filter is disposed over the conductive feature, and wherein the color filter physically contacts the passivation layer lining the back-side of the device wafer.