SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PURPOSE:To eliminate occurrence of latch up completely, by employing a dielectric isolation technique for insulation between a vertical type MOS and a horizontal type MOS in an output circuit part of high breakdown strength. CONSTITUTION:A dielectric isolation substrate on an output circuit part of high breakdown strength is composed mostly of a polycrystalline semiconductor substrate 13. P-type single-crystal semiconductor regions 15 to 17 are buried insularly with a dielectric film 14 in between on a main surface 11 side of this substrate. Two n-type layers and p<+> type layers serving as sources in the n-type layers are formed in the region 15 so as to compose a vertical type p-MOS. Two n<+>type layers serving as a source and a drain respectively are formed in the region 17 so as to compose a horizontal type n-MOS. P-type single-crystal layers 15' and 16' are formed to penetrate through dielectric films on the bottom parts in the region 15 and 16 and extended to an electrode layer 8 formed on a main surface 12 of this substrate. Such composition realizes good endurance to latch up and high integrity.