A method for fabricating a semiconductor device includes forming a plurality of gate structures on a semiconductor substrate. The plurality of gate structures are arranged in a plurality of lines, wherein an end-to-end spacing between the lines is smaller than a line-to-line spacing between the lines. The method further includes forming an etch stop layer over the gate structures, forming an interlayer dielectric over the gate structures, and forming a dielectric film over the gate structures before the interlayer dielectric is formed. The dielectric film merges in end-to-end gaps formed in the end-to-end spacing between the gate structures.