Patent ID: 6706550
Filing Date: 2004-03-16
Classification: H01L

Abstract:
A method for forming a pinned photodiode for an image sensor, the method comprising the steps of:preparing a semiconductor layer of a first conductivity type; forming a field oxide layer to isolate an active region from a field region; forming a first ion implantation mask, an edge of which covers a portion of the active region adjacent to the field region; opening the active region; forming a first doping region through two ion implantation processes, each implantation process using a different ion implantation energy; removing the first ion implantation mask; forming a second ion implantation mask, an edge of which is positioned at a boundary between the field and active regions; opening the active region; and forming a second doping region between a surface of the semiconductor layer and the first doping region, wherein a thickness between the first doping region and the surface of the semiconductor layer is made thin by the two ion implantation processes.