A method includes: forming a structure on a frontside of a substrate, the structure including a first and a second source/drain body located in a first and a second source/drain region, respectively, and a channel body including a channel layer extending between the first and second source/drain bodies; forming a trench beside the first source/drain region by etching the substrate such that a lower portion of the trench undercuts the first source/drain region; forming a liner on the trench; forming an opening in the liner underneath the first source/drain region; and forming a dummy interconnect in the trench; where the method further includes exposing the dummy interconnect from a backside of the substrate; removing the dummy interconnect selectively to the liner; and forming a buried interconnect of a conductive material in the trench, where the buried interconnect is connected to the first source/drain body via the opening in the liner.