Method for fabricating semiconductor device

摘要

A gate pattern is formed on a first region of a substrate. An epitaxial layer is formed on a second region of the substrate. A recess is formed in the second region of the substrate by etching the epitaxial layer and the substrate underneath. The first region is adjacent to the second region.

主权项

1. A method for fabricating a semiconductor device comprising:
forming a gate pattern on a first region of a substrate; forming an epitaxial layer on a second region of the substrate; and forming a recess in the second region of the substrate by etching the epitaxial layer and the substrate underneath the epitaxial layer, wherein the first region is adjacent to the second region, wherein the etching of the epitaxial layer and the substrate comprises:
etching the epitaxial layer and the substrate to form a recessed portion in the substrate, wherein the recessed portion includes a flat bottom in the second region and a curved surface extended from the flat bottom to the gate pattern; andetching the recessed portion using an etchant having different etch rates depending on a crystallographic orientation, thereby forming the recess having a tip thereof under the gate pattern, and wherein the epitaxial layer is entirely removed during forming the recess in the second region of the substrate.