Semiconductor device and manufacturing method thereof

A method of manufacturing a semiconductor device, comprising the steps of:

• (a) providing a wiring substrate including
• a first package substrate-forming area having a first main surface, a first back surface opposite to the first main surface, a first pad formed on the first main surface, and a first plating film formed on the first pad,
• a second package substrate-forming area having a second main surface, a second back surface opposite to the second main surface, a second pad formed on the second main surface, and a second plating film formed on the second pad, and being arranged adjacent to the first package substrate-forming area,
• a dicing groove including a bottom surface, a first side surface, and a second side surface facing the first side surface, and being arranged at four sides of each of said first and second package substrate-forming areas including between the first and second package substrate-forming areas,
• a first wiring line having one end formed in the first package substrate-forming area and connected with the first pad, and another end terminated at the first side surface of the dicing groove, and
• a second wiring line having one end formed in the second package substrate-forming area and connected with the second pad, and another end terminated at the second side surface of the dicing groove;
• (b) mounting first and second semiconductor chips on the first and second package substrate-forming areas, respectively;
• (c) electrically connecting the first and second semiconductor chips with the first and second pads, respectively;
• and
• (d) cutting the wiring substrate by using a dicing blade to separate the first package substrate-forming area from the second package substrate-forming area,
• wherein the step (d) includes arranging the dicing blade inside the dicing groove such that the first and second side surfaces are not contacted by the dicing blade.