To provide a manufacturing method for a semiconductor device capable of forming the impurity introduction region of a photodiode having a part formed at the lower part of a gate electrode without oblique rotation implantation or excessive thermal diffusion.

By a photoengraving method, a photoresist 30 having a pattern in which the end of a gate structure 15 and the formation scheduled region of the photodiode 18 adjacent to the end are opened is formed. Then, by using the photoresist 30 for an implantation mask, N-type impurities 31 such as phosphorus are vertically implanted under an implantation condition that energy is 300 to 700 keV and a dosage is 1E12 to 1E14 ions/cm2. Thus, an N-type impurity introduction region 17 is formed within the upper surface of a P well 11. At the time, since the N-type impurities 31 can reach the inside of the P well 11 through the gate structure 15, the N-type impurity introduction region 17 is formed at the lower part of the gate structure 15 as well.