Semiconductor device and method of manufacturing the semiconductor device

Abstract

Unintended full siliciding of a polysilicon gate electrode is prevented. The invention provides a method of manufacturing a semiconductor device, the method including: forming a stack structure by stacking a gate insulating film and a silicon layer in this order on a substrate; forming an offset spacer along the side surfaces of the stack structure, the offset spacer including a SiN film; cleaning an exposed region of an upper surface of the silicon layer with a chemical solution after the forming the offset spacer; forming a metal film after the cleaning, the metal film covering at least the exposed region; and performing siliciding through a heating process after the forming the metal film. The SiN film of the offset spacer is a SiN film formed by ALD at 450° C. equal to or higher, or a SiN film having a tensile/compressive stress of 1 Gpa or higher. The chemical solution is DHF having a ratio by weight of 1/100 or higher in HF/H2O or buffered hydrofluoric acid.

Dependencies are inferred from the claim text.