A memory device including an SOI substrate with a buried dielectric layer having a thickness of less than 30 nm, and a trench extending through an SOI layer and the buried dielectric layer into the base semiconductor layer of the SOI substrate. A capacitor is present in a lower portion of the trench. A dielectric spacer is present on the sidewalls of an upper portion of the trench. The dielectric spacer is present on the portions of the trench where the sidewalls are provided by the SOI layer and the buried dielectric layer. A conductive material fill is present in the upper portion of the trench. A semiconductor device is present on the SOI layer that is adjacent to the trench. The semiconductor device is in electrical communication with the capacitor through the conductive material fill.