Patent ID: 8026181

Claim:
A manufacturing method for semiconductor chips, the method comprising: performing plasma etching on a second surface of a semiconductor wafer, the semiconductor wafer having a first surface on which an insulating film and semiconductor devices are disposed, wherein the semiconductor devices are placed in a plurality of device-formation-regions defined by dividing regions and the insulating film is placed in the dividing regions, wherein a mask for defining the dividing regions is placed on the second surface of the semiconductor wafer, the second surface being located opposite from the first surface, whereby portions that correspond to the dividing regions are removed and the insulating film is exposed; removing corner portions on a first surface side of the semiconductor wafer in contact with the insulating film in the device-formation-regions by continuously performing the plasma etching in a state in which exposed surfaces of the insulating film are charged with electric charge due to ions in plasma; after said removing the corner portions on the first surface side, removing the exposed insulating film from the second surface so that the device-formation-regions are separated into individual semiconductor chips; removing the mask from surfaces of the semiconductor chips corresponding to the second surface of the semiconductor wafer; and after said removing the mask, removing corner portions on the surfaces of the semiconductor chips from which the mask has been removed by further performing plasma etching on the surfaces of the semiconductor chips from which the mask has been removed, whereby the semiconductor chips each of which includes one of the semiconductor devices are manufactured.