4F2 DRAM Including Buried Bitline

Disclosed are approaches for forming 4F2 vertical DRAM devices including buried bitlines. One DRAM device may include a plurality of bitlines between a plurality of vertical structures extending from a substrate, and a bottom source/drain formed in each of the plurality of vertical structures in a saddle area, wherein the saddle area comprises a saddle trench formed through the plurality of vertical structures. The DRAM device may further include a dielectric film formed over the plurality of vertical structures in the saddle area, wherein the dielectric film is present along a portion of the plurality of bitlines and along just a first sidewall the plurality of vertical structures in the saddle area, and a fill material over the plurality of vertical structures of the saddle area, wherein the fill material directly contacts the plurality of bitlines.