PURPOSE: To eliminate the limitation of the position of a GND pad to a place near an island supporting lead, by providing a convex part in an island of a lead frame located near the GND pad, and by connecting the convex part to the GND pad on a pellet by wire bonding.

CONSTITUTION: A lead frame is prepared by providing a convex part 8 in an island 2 on a pellet 1 which is located near a GND pad 4, and by connecting a specified GND lead 5 to an island supporting lead 7. The lead frame thus prepared being used, the GND pad 4 is connected to the convex part 8 by wire bonding. By providing the convex part 8 in this way and by applying wire bonding to this part as a part to which a brazing material 6 for fixing the pellet does not expand, the same effect as by applying earth bonding directly to the island is obtained. This constitution has the effects that the limitations to the position and the number of the GND pads can be eliminated and that the width of a wiring connected to the GND pad, which is enlarged more than required in some kinds of products, can be minimized, etc. and makes it possible to facilitate the design of pellets, etc.