forming a plurality of first recesses in a semiconductor substrate at a first side of the semiconductor substrate, the first recesses extending in an X-direction and arranged in a Y-direction transverse to the X-direction;

forming a hard mask layer in the first recesses;

etching the semiconductor substrate to form a plurality of second recesses that extend along the Y-direction at the first side of the semiconductor substrate;

removing a portion of the hard mask layer in the second recesses;

forming an epitaxial layer in the second recesses to form first features of semiconductor devices of the semiconductor circuit;

forming second features of the semiconductor devices at the first side of the semiconductor substrate, the second features overlapping a remaining portion of the hard mask layer that remains after removing the portion of the hard mask layer; and

etching a to-be-removed portion of the epitaxial layer from a second side of the semiconductor substrate, wherein the second side is opposite to the first side, and the remaining portion of the hard mask layer covers portions of the second features of the semiconductor devices during the etching of the to-be-removed portion of the epitaxial layer to protect the portions of the second features of the semiconductor devices from being damaged.