Abstract: In a semiconductor integrated circuit consisting of a plurality of semiconductor chips each having a plurality of islands, two or more bonding wires each having different potential are connected to bonding pads formed on the surface of semiconductor chips. The islands are isolated by a dielectric isolation region comprising polysilicon film and isolation film formed in an isolation groove. The polysilicon film is exposed at a dicing line region around the semiconductor chip and a surface of the polysilicon film is made highly resistive. If two or more bonding wires come into contact with the polysilicon film exposed at a peripheral region of the semiconductor chip to cause short circuit, parasitic conductance does not occur between two or more bonding wires because the peripheral region of the semiconductor chip has high resistivity, whereby variation in characteristics of the semiconductor integrated circuit can be suppressed.

Abstract: A bidirectional semiconductor switch employs two insulated gate semiconductor devices such as insulated gate bipolar transistors (IGBTs) that are connected oppositely in parallel, with the collector of one of the IGBTs being connected to the emitter of the other. The gates of the IGBTs are biased by gate controllers that are potentially independent of each other. The semiconductor switch is capable of controlling a direct current as well as an alternating current at a low ON-state voltage, reducing a conduction loss, and improving efficiency.