US Patent 7365384 Trench buried bit line memory devices and methods thereof

A memory device includes isolation trenches that are formed generally parallel to and along associated strips of active area. A conductive bit line is recessed within each isolation trench such that the uppermost surface of the bit line is recessed below the uppermost surface of the base substrate. A bit line contact strap electrically couples the bit line to the active area both along a vertical dimension of the bit line strap and along a horizontal dimension across the uppermost surface of the base substrate.