A method of forming a semiconductor device includes forming a spacer layer over a plurality of transistor gate structures, the transistor gate structures being formed over both active and shallow trench isolation (STI) regions of a substrate. The spacer layer is subjected to a directional etch so as to form sidewall spacers adjacent the plurality of transistor gate structures, and a horizontal fill portion of the spacer layer remains in one more recesses present in the STI regions so as to substantially planarize the STI region prior to subsequent material deposition thereon.