| 摘要 |
PURPOSE:To improve the yield of taping and mounting of a chamfered semiconductor device by forming leads in such a manner that the bent end folded obliquely downwardly from the course of the end is coincident to the lower surface of a package or slightly retracted. CONSTITUTION:Long leads 3 are stepwisely formed by clamping lower and upper molds 10, 11 to be sufficiently long, and the accuracy of bending size is preferable. Short leads 5 are fixed at the root with holding parts 12, 13 by clamping the molds 10, 11, and bend at 45 deg. with a retainer, punching unit 17, 18 for obliquely bending by the downward movement of the punch 14. The unit 18 is always contacted with the leads 2, thereby effectively bending them. Since bending at a right angle is not applied, a force of pulling the leads 2 from the package 1 is small. The variation in the length of the leads 5 at the lead cutting time or in the end position of the leads 5 due to irregular position of the package 1 is presented in a triangular function, and the irregularity of the height of the ends of the leads 5 is made small. |
