Patent attributes
In a method of manufacturing a semiconductor device according to an embodiment, a lead frame is provided, the lead frame having a trench part formed thereon so as to communicate bottom surfaces of a first lead and a second lead, which are coupled to each other between device regions adjacent to each other. Then, after a part of a coupling part between the first and second leads is cut by using a first blade, metal wastes formed inside the trench part are removed. Then, after the metal wastes are removed, a metal film is formed on exposed surfaces of the first and second leads by a plating method, and then, a remaining part of the coupling part between the first and second leads is cut by using a second blade. At this time, the cutting is performed so that the second blade does not contact the trench part.