According to a CMOS image device and a method of manufacturing same, dark current is decreased by a local impurity region. The image device includes a semiconductor substrate, and a transfer gate formed on a predetermined portion of the semiconductor substrate and electrically insulated from the semiconductor substrate. A photodiode is formed in the semiconductor substrate on one side of the transfer gate, and a floating diffusion region is formed on the semiconductor substrate in the other side of the transfer gate. A local impurity region of a first conductivity type is formed to be partially overlapped the transfer gate between the photodiode and the floating diffusion region.

A pixel image sensor has a high shutter rejection ratio that prevents substrate charge leakage to a floating diffusion storage node of the pixel image sensor and prevents generation of photoelectrons within the floating diffusion storage node and storage node control transistor switches of the pixel image sensor. The pixel image sensor that prevents substrate charge leakage of photoelectrons from pixel image sensor adjacent to the pixel image sensor. The pixel image sensor is fabricated on a substrate with an isolation barrier and a carrier conduction well. The isolation barrier formed underneath the floating diffusion storage node allows effective isolation by draining away the stray carriers and preventing them from reaching the floating diffusion storage node. The carrier conduction well in combination with the deep N-well isolation barrier separates the pinned photodiode region from the deep N-well isolation barrier that is underneath the floating diffusion storage node.

A structure (and method for forming the same) for an image sensor cell. The structure includes (a) a semiconductor substrate; (b) a charge collection well on the substrate, the charge collection well comprising a semiconductor material doped with a first doping polarity; (c) a surface pinning layer on and in direct physical contact with the charge collection well, the surface pinning layer comprising a semiconductor material doped with a second doping polarity opposite to the first doping polarity; and (d) an electrically conducting push electrode being in direct physical contact with the surface pinning layer but not being in direct physical contact with the charge collection well.

A novel image sensor cell structure and method of manufacture. The imaging sensor comprises a substrate, a gate comprising a dielectric layer and gate conductor formed on the dielectric layer, a collection well layer of a first conductivity type formed below a surface of the substrate adjacent a first side of the gate conductor, a pinning layer of a second conductivity type formed atop the collection well at the substrate surface, and a diffusion region of a first conductivity type formed adjacent a second side of the gate conductor, the gate conductor forming a channel region between the collection well layer and the diffusion region. Part of the gate conductor bottom is recessed below the surface of the substrate. Preferably, a portion of the gate conductor is recessed at or below a bottom surface of the pinning layer to a depth such that the collection well intersects the channel region.

A method for fabricating a photodiode of a CMOS image sensor is disclosed, to improve a charge accumulation capacity in the photodiode, which includes the steps of defining a semiconductor substrate as an active area and a field area by forming an STI layer; firstly implanting impurity ions for formation of the photodiode to the semiconductor substrate of the active area; secondarily implanting impurity ions for formation of the photodiode to the semiconductor substrate being adjacent to the STI layer; and forming a photodiode ion-implantation diffusion layer by diffusing the implanted impurity ions with a thermal process.