Image sensors and methods of manufacturing the same

A method of manufacturing an image sensor, comprising:

• forming a plurality of photodiodes inside a photoelectric conversion area of a substrate on which a floating diffusion area is separated from the photoelectric conversion area, wherein the plurality of photodiodes are arranged in a vertical direction;
• forming a recess on the substrate between the photoelectric conversion area and the floating diffusion area;
• forming a gate insulation layer along a surface profile of the substrate having the recess, wherein the gate insulation layer is formed on a sidewall and bottom of the recess and on the surface of the substrate around the recess;
• forming a pure polysilicon layer on the gate insulation layer along the surface profile of the substrate;
• implanting impurities into the pure polysilicon layer to form a gate conductive layer including polysilicon doped with impurities on the gate insulation layer along the surface profile of the substrate having the recess;
• and
• patterning the gate insulation layer and the gate conductive layer to form a transfer gate electrode including a gate insulation pattern and a gate conductive pattern including the polysilicon doped with the impurities along the surface profile of the substrate having the recess, wherein the transfer gate electrode is formed on the sidewall and the bottom of the recess and on the surface of the substrate around the recess and includes a cavity over a central portion of the recess.