A method for fabricating a semiconductor device is provided. The method includes forming a plurality of gate structures having asymmetric sidewalls including a tall side and a short side. Adjacent ones of the plurality of gate structures are separated by a tall side-tall side region and a short side-short side region. The method further comprises forming a spacer layer over the plurality of gate structures and a bottom surface of the tall side-tall side region and the short side-short side region, depositing an oxide layer over the spacer layer, etching the bottom surface portions of the oxide layer, and selectively etching the sidewall portions of the oxide layer in the tall side-tall side region.