An intermediate semiconductor structure in fabrication includes a substrate. A plurality of gate structures is disposed over the substrate, with at least two of the gate structures separated by a sacrificial material between adjacent gate structures. A portion of the sacrificial material is removed to form openings within the sacrificial material, which are filled with a filler material having a high aspect ratio oxide. The excess filler material is removed. A portion of the gate structures is removed to form gate openings within the gate structures. The gate openings are filled with gate cap material and the excess gate cap material is removed to create a substantially planar surface overlaying the gate structures and the sacrificial material to control sacrificial oxide recess and gate height.