A manufacturing method of a semiconductor device in which a semiconductor substrate having a plurality of semiconductor chips formed on one of principal surfaces of the substrate is cut into the plurality of semiconductor chips through dicing, comprising the steps of:
- performing a first cutting process on one of the principal surfaces of the substrate to produce two cutting grooves between two neighbouring ones of the plurality of semiconductor chips, each cutting groove being adjacent to one of the neighbouring ones of the plurality of semiconductor chips;
- and
- performing a second cutting process on the other of the principal surfaces of the substrate to produce a cutting groove overlapping the two cutting grooves produced by the first cutting process.