SEMICONDUCTOR INTEGRATED CIRUCIT DEVICE

PURPOSE:To stabilize an operation by disposing a power source plate provided in a cavity of an IC package in parallel with the main surface of a semiconductor chip, and connecting the plate to the chip via bonding wires extending in a direction perpendicular to the main surfaces. CONSTITUTION:A power source plate 12 is provided in parallel with a main surface of a semiconductor chip 7 in a gap between the chip 7 and a cap 4 in the cavity 6 of an IC package 1. A constant-potential plate 12a of the plate 12 and a reference potential plate 12b are insulated by an insulating layer 13, and connected to outer leads 11 and the chip 7 via through holes and bonding wires 14. The connection of the chip 7 via the wires 14 is conducted via an opening 15a, constant-potential, reference potential bonding pads are provided directly thereabove, and the wires 14 are extended in a direction perpendicular to the main surface of the chip 7 and the plate 12. Thus, stabilization of an IC in a microwave band and reduction in influences of a particle beam and an electromagnetic wave can be performed.