SOI SUBSTRATE AND SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an SOI substrate and a semiconductor integrated circuit device which do not require a dedicated region where a structure for reducing noises, such as a decoupling capacitor, and guard ring, is arranged. SOLUTION: A p--type silicon support substrate 2 is provided, a p+-type silicon layer 3 is provided on the support substrate 2, and n+-type silicon layers 4 and p+-silicon layers 12 are alternately formed thereon. The p+-type silicon layer 3 and the n+-type silicon layers 4 are set higher in impurity concentration than the support substrate 2. A buried oxide film 5 and an SOI layer 6 are provided on all the surfaces of the n+-type silicon layers 4 and the p+-silicon layers 12. The p+-silicon layer 3 is connected to a grounding potential interconnect line GND, and the n+-type silicon layers 4 are connected to a power supply potential interconnect line VDD. By this setup, the decoupling capacitor C1 connected to a power supply in parallel is provided between the p+-type silicon layer 3 and the n+-type silicon layers 4. COPYRIGHT: (C)2004,JPO&NCIPI