Patent ID: 7880259

Claim:
A solid-state image sensor comprising: an output gate electrode formed on a semiconductor substrate; a first impurity region formed on said semiconductor substrate at a first distance from said output gate electrode for receiving signal charges; a reset gate electrode formed at a second distance from said first impurity region for discharging unnecessary said signal charges after extraction of a voltage signal from said first impurity region; and a second impurity region having the same conductivity type as said first impurity region, said second impurity region being formed on a partial region of said semiconductor substrate located between said first impurity region and said output gate electrode at a third distance from said output gate electrode, wherein said second impurity region has an impurity concentration higher than the impurity concentration of the remaining region of said semiconductor substrate excluding said second impurity region located between said first impurity region and said output gate electrode, said remaining region has the same conductivity type as said second impurity region, said second impurity region has an average impurity concentration lower than an average impurity concentration of said first impurity region, said first distance between said first impurity region and said output gate electrode is larger than said second distance between said first impurity region and said reset gate electrode, and an insulating film is formed between said output gate electrode and said reset gate electrode, and said first impurity region.