A modified layer 5 and an altered layer 8 are formed outside a dicing point of a dicing area 3. Thus without forming another interface between different physical properties on the dicing point, it is possible to prevent chipping from progressing along a crystal orientation from an interface between a semiconductor element 2 and a semiconductor substrate 1 and from a surface of the semiconductor element during dicing, thereby suppressing the development of chipping to the semiconductor element.