Image sensor device structure with doping layer in light-sensing region

An image sensor device structure, comprising:

• a p-type substrate, wherein the p-type substrate has a first surface and a second surface;
• an interconnect structure formed on the first surface of the p-type substrate;
• an n-type light-sensing region formed in the substrate;
• a p-type doping region inserted into the n-type light-sensing region from the second surface of the substrate, wherein the p-type doping region comprises a p-type doping layer and an oxide layer formed over the p-type doping layer;
• and
• a deep isolation ring surrounding the n-type light-sensing region, wherein the deep isolation ring comprises the p-type doping layer and the oxide layer.

An image sensor device structure, comprising:

• a substrate, wherein the substrate has a first surface and a second surface;
• an interconnect structure formed on the first surface of the substrate;
• a light-sensing region formed in the substrate;
• a doping region inserted into the light-sensing region, wherein the doping region comprises a doping layer;
• a deep isolation ring surrounding the light-sensing region, wherein the doping layer extends from the doping region to a position which is in the deep isolation ring;
• a plurality of color filters formed on the doping region and the deep isolation ring, wherein the doping layer protrudes into the light-sensing region along a direction farther away from the color filters;
• and
• a plurality of microlens structures formed on the color filters.