Complementary metal grid and deep trench isolation in CIS application

A CMOS image sensor structure, comprising:

• a substrate;
• and
• a plurality of pixel portions disposed adjacent to each other on the substrate, wherein each of the pixel portions comprises a central area, wherein each of the pixel portions comprises:
• a device layer disposed on the substrate, wherein a plurality of trenches are formed in the device layer and the substrate;
• an anti-reflective coating layer conformally covering the device layer, the substrate, and the trenches;
• a plurality of discrete reflective structures disposed on the anti-reflective coating layer in the trenches respectively;
• a plurality of discrete metal blocking structures overlying the anti-reflective coating layer, wherein each of the reflective structures is located between any two adjacent ones of the metal blocking structures, and the metal blocking structures and the reflective structures are staggered and surround the central area;
• a passivation layer conformally covering the metal blocking structures, the anti-reflective coating layer, and the reflective structures;
• and
• a color filter disposed on the passivation layer.

A CMOS image sensor structure, comprising:

• a substrate;
• and
• a plurality of pixel portions disposed adjacent to each other on the substrate, wherein each of the pixel portions comprises a plurality of intersection areas, a plurality of border areas each of which is located between any two adjacent ones of the intersection areas, and a central area surrounded by the intersection areas and the border areas, wherein each of the pixel portions comprises:
• a device layer disposed in the intersection areas, the border areas, and the central area on the substrate, wherein a plurality of trenches are formed in the device layer and the substrate corresponding to the border areas respectively;
• an anti-reflective coating layer conformally covering the device layer, the substrate, and the trenches;
• a plurality of discrete reflective structures disposed on the anti-reflective coating layer in the trenches respectively;
• a buffer layer disposed on the anti-reflective coating layer and the reflective structures;
• a plurality of discrete metal blocking structures disposed on the buffer layer and overlying the anti-reflective coating layer in the intersection areas respectively, wherein the metal blocking structures and the reflective structures are staggered and surround the central area;
• a passivation layer conformally covering the metal blocking structures and the buffer layer;
• and
• a color filter disposed on the passivation layer in the intersection areas, the border areas, and the central area.