SEMICONDUCTOR DEVICE AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To improve performance of a semiconductor device by improving stability of operations at the time of writing and at the time of reading of an SRAM on an SOI substrate.SOLUTION: A manufacturing method of a semiconductor device comprises: composing a MOSFETQT2 for transfer which composes an SRAM on an SOI substrate; and forming a diffusion layer D2 into which a high-concentration p-type impurity is introduced on a top face of a semiconductor substrate SB just below a source-drain region connected to a storage node to make an impurity distribution in the semiconductor substrate SB be asymmetric centered on a region just below a gate electrode G1. Accordingly, a threshold voltage of the MOSFETQT2 for transfer at the time of writing of the SRAM is decreased and a threshold voltage at the time of reading of the SRAM is increased.