A semiconductor structure is described. The structure includes a trench opening formed in a semiconductor substrate having a semiconductor-on-insulator (SOI) layer and a buried insulating (BOX) layer; and a filling material formed in the trench opening, the filling material forming a "V" shape within the trench memory cell, wherein the "V" shape includes a top portion substantially adjacent to a top surface of the BOX layer. A method of fabricating the semiconductor structure is also described. The method includes forming a trench opening in a semiconductor substrate having an SOI layer and a BOX layer; laterally etching the BOX layer such that a portion of the trench opening associated with the BOX layer is substantially greater than a portion of the trench opening associated with the SOI layer; filling the trench opening with a filling material; and recessing the filling material.