Goldstar Electron Co., Ltd.

Seo K Lee

Uja Shinji

Uya Shinji

Yong Seung Park

A horizontal charge coupled device (HCCD) is provided with a multiple reset gate in order to establish a more stable, less noisy voltage in an output node floating diffusion. Charges are transferred from an input of the HCCD to the floating diffusion by multiple, overlapping gate structures. Signal charges are detected or read out from the floating diffusion through an amplifier/inverter circuit. Periodically, the voltage of the floating diffusion is established to a reference level by application of a reset signal to a multiple reset gate structure, which results in charges in the floating diffusion being transferred to a reset drain. Noise induced by the reset operation is lessened on average due to the multiple reset gate structure.

Horizontal charge coupled device having a multiple reset gate

A CCD type solid-state image sensor a n type silicon substrate, a first p type well formed over the substrate, photodiode regions deeply and widely formed in the first well, second p type wells formed in the first well, each of the second well being overlapped with each corresponding photodiode region and each photodiode region preceding to the corresponding photodiode region, n type VCCD channel regions respectively formed in the second wells, p type transfer gate channel regions each formed in each one of the second p type wells between each photodiode region and each corresponding VCCD channel region, p type channel stop regions respectively formed in the second wells, each of the channel stop regions being adapted to isolate each corresponding VCCD channel region from each corresponding preceding photodiode region, p type impurity regions respectively formed beneath surfaces of the photodiode regions, a thin insulating film formed over the entire exposed surface of the resulting structure, transfer gates formed on the thin insulating film to be respectively disposed over the second wells, an interlayer insulating film formed on the thin insulating film to cover the transfer gate electrodes, and a photoshield film formed over the entire exposed surface of the resulting structure except for portions respectively disposed over the photodiode regions.

CCD type solid-state image sensor

A CCD image sensor comprising: a semiconductor substrate of a first conductivity type connected to a ground; an impurity region of a second conductivity type formed in the surface of the semiconductor substrate of the first conductivity type, to serve as a blooming prevention layer; an impurity region of the first conductivity type formed in the surface of the semiconductor substrate, so that it encloses the impurity region of the second conductivity type serving as a blooming prevention layer, to serve as a potential barrier layer; an impurity region of the second conductivity type formed in the surface of the semiconductor substrate of the first conductivity type so that it encloses the impurity region of the first conductivity type serving as a potential barrier layer, to serve as a light receiving region; an insulation film which is formed on the surface of the semiconductor substrate of the first conductivity type and has contact holes at both edges of the impurity region of the second conductivity type, serving as a blooming prevention layer; silicide films filled in the contact holes; and a light shield conductor film which is formed on the surface of the remaining insulation film, except for a portion between the silicide films and the surfaces of the silicide films, and is connected to a voltage source.

Method of making charge coupled device image sensor

A charge transfer device and a solid state image sensor using the same, capable of transferring signal charge at a high signal to noise ratio (S/N ratio) and preventing an occurrence of dark current. They include a double-layered charge transfer path structure provided by forming a surface channel region on a buried channel region formed in a semiconductor substrate, the surface channel region having a conductivity opposite to that of the buried channel region. The surface channel region of the doubled-layered structure is used for accumulating dark current generated from boundary surfaces between the substrate and a gate insulating film, whereas the buried channel region is used for transferring optical signal charge. Where minus and/or plus drive voltages are applied to the transfer electrodes, there is no increase in dark current, in accordance with the present invention. The quantity of transferred signal charge can be greatly increased.

Charge transfer device and solid state image sensor using the same

Charge coupled device image sensor

A CCD image sensor of an interlaced scanning type comprising a plurality of uniformly spaced photodetectors arranged in series in vertical and horizontal directions, a plurality of VCCD regions arranged between sets of said photodetectors arranged in the vertical directions, a plurality of channel stop regions for electrically isolating said plurality of photodetectors from one another, a plurality of gate electrodes formed on said VCCD regions, each of said plurality of gate electrodes being connected simultaneously to transfer gate electrodes of adjacent ones of said plurality of photodetectors on odd and even horizontal lines, a plurality of barrier layers, each formed at a portion of each of said VCCD regions corresponding to a boundary with each of said gate electrodes on said VCCD regions, for forming a desired potential barrier, and a HCCD region formed under said plurality of VCCD regions, for transferring signal charges from said VCCD regions to an output stage. Therefore, in accordance with the present invention, the gate electrodes can be reduced from four of the prior art to two in number, resulting in simplification in construction and manufacturing process thereof. Also, the reduction in number of the gate electrodes to two allows the driving system to be simple.

CCD image sensor of interlaced scanning type

This invention relates to a method of forming a charge coupled device (CCD) channel which has a trench-type multi-potential profile. To form the multi-potential profile, ion implantation is performed several times with a self-alignment mask using a polysilicon layer. This method simplifies the fabrication process and prevents charges from diffusing over the entire CCD channel laterally when the amount of charge is small. This results in charge confinement in a trench in the middle of the channel, enhancing self-induced field and fringing field. Consequently, charge transfer efficiency is improved for small amount of charge.

Growing community of inventors

Sungnam, South Korea

Seo K Lee