On a plane of a semiconductor wafer, two types of in-plane regions comprising full-width non-ion-implantation regions and partial ion implantation regions, which are alternately arranged one or more times in a direction orthogonal to a scanning direction of an ion beam are created. During the creation of the partial ion implantation regions, reciprocating scanning using the ion beam can be repeated until the target dose can be satisfied while performing or stopping ion beam radiation onto the semiconductor wafer in a state in which the semiconductor wafer can be fixed. During the creation of the full-width non-ion-implantation regions, the semiconductor wafer can be moved without performing the ion beam radiation onto the semiconductor wafer. Then, by repeating fixing and movement of the semiconductor wafer plural times, ion implantation regions and non-ion-implantation regions are created in desired regions of the semiconductor wafer.
