DRY ETCHING METHOD OF METAL GATE

摘要

PROBLEM TO BE SOLVED: To obtain an etching shape having no p-n difference while preventing a base HfSiON film from penetrating during dry etching of metal gates. SOLUTION: In the dry etching method of a wafer having the base HfSiON film 16 formed on a surface of a silicon substrate, metal gates composed of a TaSiN film 14 and a TiN film 15 formed thereupon, a W film 13 formed thereupon, an SiN film 12, an antireflection film 11, and a resist film 10, the metal gates 14 and 15 are dry-etched under a pressure of≤0.5 Pa using mixed gas of a CF-based gas (CHF3, CF4, etc.), and chlorine and nitrogen gases which has a high selection ratio for the base HfSiON film 16. COPYRIGHT: (C)2009,JPO&INPIT