Patent ID: 7923297

Claim:
A method of manufacturing a semiconductor device, said method comprising the steps of: a) preparing a wiring board having a top surface and a bottom surface opposite to said top surface, said wiring board having a plurality of mounting areas on said top surface for boarding a plurality of semiconductor chips; b) mounting a plurality of semiconductor chips on said plurality of mounting areas on said top surface of said wiring board; c) connecting said plurality of semiconductor chips and said wiring board by a plurality of connecting wires; d) sealing said plurality of semiconductor chips and said plurality of wires in block by resin; e) forming a plurality of soldering balls on said bottom surface of said wiring board; f) forming a plurality of semiconductor packages by individually separating said wiring board with said resin; wherein, each of said plurality of semiconductor chips having: a silicon substrate; a plurality of transistors formed on the surface of said silicon substrate; a first insulating film of silicone oxide formed on said plurality of transistors; a multi layer wiring structure formed on said first insulating film; a second insulating film formed between wiring layers of said multi layer wiring structure, said second insulating film having a lower dielectric constant than said silicon oxide; and wherein, each of said semiconductor chips having an inclined surface on each of side surfaces thereof, said inclined surface being formed by cutting an upper surface of a semiconductor wafer by a blade having a processed V-shape at the tip thereof.