Patent ID: 7517777

Claim:
A method of manufacturing a semiconductor device comprising a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type in contact with a first major surface of the first semiconductor layer, the second semiconductor layer being doped more heavily than the first semiconductor layer; a first electrode in electrical contact with the second semiconductor layer; a third semiconductor layer of the first conductivity type in contact with a second major surface of the first semiconductor layer, the third semiconductor layer being doped more heavily than the first semiconductor layer; and a second electrode in electrical contact with the third semiconductor layer, the method comprising the steps of: irradiating a charged particle beam to one of the first major surface or the second major surface of the first semiconductor layer to introduce crystal defects into the first semiconductor layer after forming the second semiconductor layer and the first electrode on the first major surface of the first semiconductor layer; grinding the one major surface of the first semiconductor layer into which the crystal defects have been introduced; implanting impurity ions of the first or second conductivity type from the surface of the first semiconductor layer exposed by the grinding step; and irradiating laser beams to the exposed surface of the first semiconductor layer to a predetermined depth from the defective state caused by the crystal defects introduced therein, to make the implanted impurity atoms electrically active and to recover the region from the surface of the first semiconductor layer irradiated by the laser beams.