Patent ID: 6573937
Filing Date: 2003-06-03
Classification: H01L

Abstract:
A solid image pick-up device having unnecessary charge discharging section comprising:a semiconductor substrate of first conductive type; a semiconductor well layer of second conductive type formed at the surface of said semiconductor substrate; first device isolation areas of first conductive type formed at the surface of said semiconductor well layer; a plurality of photoelectric conversion sections formed at said first device isolation areas, said photoelectric conversion sections converting optical information into electric signals; a vertical charge transfer section for transferring charges in a vertical direction out of said electric signals converted by said photoelectric conversion sections; a horizontal charge transfer section for transferring charges in a horizontal direction out of said electric signals converted by said photoelectric conversion sections; a second device isolation area of second conductive type formed in contact with said first device isolation areas, said second device isolation area having an impurity density higher than that of said semiconductor well layer; an output circuit section formed at said second device isolation area, said output circuit section outputting charges transferred by said vertical charge transfer section and said horizontal charge transfer section; an unnecessary charge discharging section formed at a side of said horizontal charge transfer section opposite to said vertical charge transfer section, said unnecessary charge discharging section discharging unnecessary charges of said vertical charge transfer section and said horizontal charge transfer section; a third device isolation area of second conductive type formed in a contact with said second device isolation area between said horizontal charge transfer section and said unnecessary charge discharging section, said third device isolation area having an impurity density higher than that of said semiconductor well layer; and a potential barrier section determining electric potential between said horizontal charge transfer section and said unnecessary charge discharging section.