摘要 |
A semiconductor process is described as follows. A plurality of dummy patterns is formed on a substrate. A mask material layer is conformally formed on the substrate, so as to cover the dummy patterns. The mask material layer has an etching rate different from that of the dummy patterns. A portion of the mask material layer is removed, so as to form a mask layer on respective sidewalls of each dummy pattern. An upper surface of the mask layer and an upper surface of each dummy pattern are substantially coplanar. The dummy patterns are removed. A portion of the substrate is removed using the mask layer as a mask, so as to form a plurality of fin structures and a plurality of trenches alternately arranged in the substrate. The mask layer is removed. |