Patent ID: 8896734
Filing Date: 2014-11-25
Classification: H01L

Abstract:
1. A solid-state image sensor comprising: a first semiconductor region of a first conductivity type; a second semiconductor region of a second conductivity type that is arranged to contact a lower face of the first semiconductor region and functions as a charge accumulation region; a third semiconductor region including an upper face contacting the second semiconductor region, a lower face, and a side face surrounded by the second semiconductor region, the third semiconductor region not contacting the first semiconductor region; a fourth semiconductor region of the second conductivity type that is arranged apart from the second semiconductor region; a fifth semiconductor region of the second conductivity type that is arranged to contact the lower face of the third semiconductor region and a lower face of the second semiconductor region; and a transfer gate that forms a channel to transfer charges accumulated in the second semiconductor region to the fourth semiconductor region, wherein a portion extending from the upper face of the third semiconductor region to the lower face of the third semiconductor region consists of (a) a semiconductor region of the first conductivity type, or (b) a semiconductor region of the second conductivity type whose impurity concentration is lower than that in the second semiconductor region.