Patent ID: 9543352
Date: 2017-01-10
CPC Classifications: H01L

Claim:
1. A backside illuminated CMOS image sensor device, comprising: a substrate having a pixel array on a front surface of the substrate; a dielectric layer disposed on a back surface of the substrate to cover a backside of the pixel array; a buffer oxide layer disposed on the dielectric layer, wherein the buffer oxide layer has a plurality of concave surfaces positioned to respectively align with each photodiode in the pixel array; a grid layer disposed on the dielectric layer and having a plurality of openings to respectively expose the concave surfaces of the buffer oxide layer; a plurality of embedded micro-lenses respectively disposed on the concave surfaces of the buffer oxide layer; and a plurality of color filter sheets respectively disposed on each of the embedded micro-lenses, wherein a refractive index of the micro-lenses is smaller than a refractive index of the buffer oxide layer.