Methods of manufacturing a semiconductor integrated circuit using selective disposable spacer technology and semiconductor integrated circuits manufactured thereby. The method includes providing a semiconductor substrate; forming gate patterns on the semiconductor substrate, wherein a first space and a second space wider than the first space are disposed between the gate patterns; forming a first impurity region in the semiconductor substrate under the first space and forming a second impurity region in the semiconductor substrate under the second space; forming insulation spacers on sidewalls of the gate patterns, wherein a portion of the second impurity region is exposed and the first impurity region is covered with the insulation spacers; etching the insulation spacers, wherein an opening width of the second impurity region is enlarged and wherein the etching is carried out with a wet etching process; and forming an interlayer insulating layer on the overall structure including the gate patterns.