Field insulator FET device and fabrication method thereof

摘要

A FinFET and a fabrication method thereof. The FinFET device includes an SOI substrate realized through a substrate, a buried oxide layer formed on the substrate, and a silicon epitaxial layer formed on predetermined areas of the buried oxide layer. A gate oxide layer is formed on the silicon epitaxial layer, and a gate electrode is formed on the gate oxide layer. A field insulator is formed on exposed areas of the buried oxide layer to thereby separate adjacent silicon epitaxial layers. Side surfaces of the silicon epitaxial layer are flattened through heat treatment. The fabrication method for a FinFET device includes forming the gate oxidation layer and the gate electrode on the SOI substrate; forming the mask pattern on the gate electrode; forming the trench by etching using the mask pattern as a mask; performing heat treatment to flatten the side surfaces of the silicon epitaxial layer; and forming the field insulator in the trench.