METHOD OF FORMING METAL LINE OF SEMICONDUCTOR DEVICE USING PROTECTION LAYER

摘要

PURPOSE: A method of forming a metal line of a semiconductor device is provided to obtain uniform line width in metal lines by preventing a sidewall of the metal line from being etched using a protecting layer. CONSTITUTION: A metal film(210) made of a Cu film, an Al film or a polysilicon layer is formed on a lower layer(200). A mask pattern(220) is formed thereon. A metal line is formed by etching selectively the metal film using an etching gas. At this time, A protection layer(230) is formed at both sidewalls of the metal line by flowing one selected from a group consisting of oxygen, ammonium or CHF3 as a reaction gas.