Technology for monolithic high-power integrated circuits using polycrystalline Si for collector and isolation walls

The fabrication technology for a high-power monolithic IC improved the breakdown characteristics and the output current capability. The maximum output power increased to 50 W and the supplied voltage of 110 V was realized. Highly doped polycrystalline Si was used as the collector walls and the isolation walls of transistors. Electrical and physical properties of the polycrystalline structure used in the power IC and the fabrication technology are also described.