MACHINING METHOD FOR DAM BAR AND SEMICONDUCTOR DEVICE

摘要

PURPOSE:To prevent a dross from projecting from a lead frame even when a dam bar is cut off by means of a laser beam. CONSTITUTION:A part 3 stretching from a lead frame 2 is formed by press, for example, substantially in the center of a dam bar 1. A semiconductor chip is then mounted and each terminal thereof is connected electrically with each lead of the lead frame. It is then sealed integrally by resin molding and the stretching part 3 is irradiated with a laser beam thus cutting off the stretching part 3, i.e., the dam bar 1. Consequently, a dross 6 adhering to the vicinity of cut end face 5 on the rear side of the lead frame 2 enters into a recessed space 7 on the rear side at the stretching part 3 and does not project from the rear surface of the lead frame 2.