a fourth pn junction between the deep n u2212 doping region 706 and the lower p epi layer 702 of course this multiple pn junction structure can be provided by alternatively forming the n type doping regions and the p type doping regions within the p epi layer 702 in order to insure that the p type doping regions have the same potential in the p epi layer 702 the shallow p 0 doping region 705 the middle p u2212 doping region 708 and the p epi layer 702 should be directly in contact with each other in the vicinity of the field oxide layer accordingly it becomes possible to accomplish complete implantation in cmos image sensor using power supply voltage of less than 3 3v eventually the ppd according to another embodiment of the present invention lets the charge capacity be larger than the prior art in fig1 which has only two pn junctions that is the increased capacity to save photogenerated charges makes it possible to obtain a desired sufficient quantum efficiency which an excellent sensor wants furthermore it is possible to obtain the deeper depletion depth than the prior art since the middle p u2212 doping region 708 the deep n u2212 doping region 706 and the shallow n u2212 doping region 710 are all completely implanted thereby.