SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a technique which improves reliability of a semiconductor integrated circuit device with an MISFET, formed in an SOI board. SOLUTION: A 0.05 to 0.2μm-thick thin film silicon layer 3 with an impurity concentration of 10<17> /cm<3> or more is formed between an LOCOS oxide film 4 and a embedded oxide film 2. Since minority carriers generated in a channel region thereby diffuse through the thin-film silicon layer 3 below the LOCOS oxide film 4, change in a threshold voltage of an MISFET by storage of the minority carriers can be restrained.