Patent attributes
By performing plasma etching on the second surface of a semiconductor wafer on the first surface of which an insulating film is placed in dividing regions and on the second surface of which a mask for defining the dividing regions are placed, the second surface being located opposite from the first surface, the insulating film is exposed from an etching bottom portion by removing portions that correspond to the dividing regions. Subsequently, by continuously performing the plasma etching in the state in which the exposed surfaces of the insulating film are charged with electric charge due to ions in the plasma, corner portions put in contact with the insulating film are removed. Subsequently, by removing the mask and thereafter performing plasma etching on the second surface, corner portions located on the second surface side are removed.
