The present invention relates to a method of forming a solid-state image pickup device. A part of Si, which is a component element of a P-type wafer, is converted into P, which is an N-type impurity, by nucleus conversion induced by the application of a neutron beam and an Si substrate 4 whose conductivity type is converted into N-type and whose specific resistivity is 10-100 OMEGA.cm, preferably 40-60 OMEGA.cm, is formed. On the Si substrate obtained as described above, a solid-state image pickup device is formed comprising a number of photodetecting parts, a vertical shift registors, a horizontal shift registor. |