Method of manufacturing image sensor

A method of manufacturing an image sensor, comprising:

• providing a substrate;
• forming a storage node in the substrate;
• forming a gate dielectric layer over the substrate;
• sequentially forming a storage gate electrode, an etch stop layer, and a first dielectric layer over the gate dielectric layer;
• forming a stop layer over the first dielectric layer;
• removing a portion of the stop layer and a portion of the first dielectric layer to form an opening, wherein the opening exposes at least a portion of the etch stop layer;
• forming a protection layer over the etch stop layer and the first dielectric layer;
• forming a shielding layer over the protection layer such that the protection layer covers a bottom surface and sidewalls of the shielding layer;
• and
• forming a second dielectric layer over the shielding layer.

A method of manufacturing an image sensor, comprising:

• forming a photosensitive device in a substrate;
• and
• forming a storage device adjacent to the photosensitive device, comprising:
• forming a P-N junction in the substrate;
• sequentially forming a gate dielectric layer, a storage gate electrode, and a first dielectric layer over the substrate;
• removing a portion of the first dielectric layer to form an opening;
• filling a protection layer into the opening to cover sidewalls and a bottom surface of the opening;
• depositing a shielding layer on the protection layer to fill up the opening;
• and
• forming a second dielectric layer over the shielding layer.