SEMICONDUCTOR DEVICE

PROBLEM TO BE SOLVED: To provide a semiconductor device, in which the size is reduced, the operational speed is increased, the electrical reliability is enhanced, and the mounting accuracy is increased. SOLUTION: In the semiconductor device, a first electrode pad 1B of a base substrate 1 is electrically connected to a second electrode pad 1A positioned on the backside. A semiconductor pellet 2 is placed with its main face turned down, on the pellet placement region in the main face of the base substrate 1. An external terminal 2A of the semiconductor pellet 2 and a second electrode pad 1A of the base substrate 1 are electrically connected with a bonding wire 6 through a slit 5 formed in the base substrate 1, and, a plurality of bonding wires are sealed with a resin-sealed body, which is formed on both sides of a first main face and a second main face of the base substrate, and continues into each other via the slit. COPYRIGHT: (C)2007,JPO&INPIT