PURPOSE: To eliminate the variation of leads and the floating of hanging leads above the upper surface of a die in a semicoductor manufacturing apparatus used to isolate a semiconductor device from a lead frame by providing a protruding member which is operated independently from a punch and a pressing plate on a die set.

CONSTITUTION: When the die set 13 of a semiconductor manufacturing apparatus 11 is operated in the direction of an arrow (y) to reach the vicinity of a bottom dead point, a punch 18 and a pressing plate 20 are respectively approximately simultaneously contacted with leads 5 and a semiconductor element placing unit 8. At this time, a protruding member 34 is contained in through holes 33, 19a, 20b. While a die set 12 is further operated to reach a bottom dead point, the punch 18 and the plate 20 respectively cut the leads 5 and hanging leads 2. On the other hand, the member 34 is protruded from the end 20a of the plate 20 at the same time of slightly delayed upon cutting, i.e., by the operation of an air cylinder 31 at the end at the bottom dead point of the die set 13, thereby dropping downwardly a semiconductor device 7.