Patent ID: 6734114
Filing Date: 2004-05-11
Classification: H01L

Abstract:
A method of manufacturing a semiconductor integrated circuit device, comprising the steps of:(a) forming a first insulation film having a relative dielectric constant higher than that of silicon nitride on the main surface of a semiconductor substrate, and then forming an oxidation prevention film on the first insulation film; (b) covering the oxidation prevention film on a first region of the semiconductor substrate, and etching the oxidation prevention film and the first insulation film on a second region of the semiconductor substrate to thereby expose the semiconductor substrate surface of the second region of the semiconductor substrate; (c) after the (b) step, subjecting the semiconductor substrate to thermal oxidation to thereby form a second insulation film comprised of silicon oxide on the semiconductor substrate surface of the second region; and (d) forming a gate electrode of a first MISFET on the first insulation film of the first region and a gate electrode of a second MISFET on the second insulation film of the second region after the oxidation prevention film on the first region is removed.