FINFET CONTACTING A CONDUCTIVE STRAP STRUCTURE OF A DRAM

摘要

A conductive strap structure in lateral contact with a top semiconductor layer is formed on an inner electrode of a deep trench capacitor. A cavity overlying the conductive strap structure is filled with a dielectric material to form a dielectric capacitor cap having a top surface that is coplanar with a topmost surface of an upper pad layer. A portion of the upper pad layer is removed to define a line cavity. A fin-defining spacer comprising a material different from the material of the dielectric capacitor cap and the upper pad layer is formed around the line cavity by deposition of a conformal layer and an anisotropic etch. The upper pad layer is removed, and the fin-defining spacer is employed as an etch mask to form a semiconductor fin that laterally contacts the conductive strap structure. An access finFET is formed employing two parallel portions of the semiconductor fin.