Patent attributes
In a semiconductor device manufacturing method, a first semiconductor region which includes a narrow portion and a wide portion is formed in an upper portion of a semiconductor substrate, a gate insulating film is formed on at least side surfaces of the narrow portion, a gate electrode is formed on the gate insulating film, a mask pattern that covers the wide portion is formed, ion implantation of an impurity is performed with the mask pattern as a mask to form an extension impurity region in the narrow portion, the mask pattern is removed, a heat treatment is performed to activate the impurity, a gate sidewall is formed on a side surface of the gate electrode, epitaxial growth of a semiconductor film is performed on the narrow portion and the wide portion after the formation of the gate sidewall, and source-drain regions is formed on both sides of the gate electrode.