Patent ID: 6893903

Claim:
A method for manufacturing a semiconductor device, comprising preparing a lead frame having at least one mounting portion including at least an island, leads, and lifting leads, and fixedly attaching a semiconductor element to the island of said lead frame, forming an insulating resin for each mounting portion after said semiconductor element is electrically connected to said leads via a thin metal wire, and separating said insulating resin individually for each said mounting portion by cutting said lead frame, wherein in said forming said insulating resin, said lead frame located at an end portion of said insulating resin is sandwiched with a plastic encapsulation mold, plastic is filled in the plastic encapsulation mold through an air vent provided on said lead frame, air and plastic are exhausted from the plastic encapsulation mold through an air vent provided on said lead frame, said air vent being located at said sandwiched lead frame, wherein said air vent includes at least one vent path including a first vent portion with a height substantially equal to a thickness of said lead frame and delineated at least partly by a first cutout in said lead frame, and further includes a second vent portion delineated at least partly by a second cutout in said lead frame outward of said first cutout.