Method of manufacturing semiconductor devices and semiconductor devices

Abstract

In a method of manufacturing a semiconductor device, a fin structure including a stacked layer of first semiconductor layers and second semiconductor layers is formed, an isolation insulating layer is formed so that the stacked layer are exposed from the isolation insulating layer, a sacrificial cladding layer is formed over at least sidewalls of the exposed stacked layer, a sacrificial gate electrode is formed over the exposed stacked layer, an interlayer dielectric layer is formed, the sacrificial gate electrode is partially recessed to leave a pillar of the remaining sacrificial gate electrode, the sacrificial cladding layer and the first semiconductor layers are removed, a gate dielectric layer wrapping around the second semiconductor layer and a gate electrode over the gate dielectric layer are formed, the pillar is removed, and one or more dielectric layers are formed in a gate space from which the pillar is removed.