Tungsten layer formation method for semiconductor device and semiconductor device using the same

摘要

A tungsten layer formation method for a semiconductor device reduces resistivity of the tungsten layer without requiring modification of the conventional manufacturing system. The method includes treating the surface of a barrier metal layer formed over a semiconductor substrate in a pressure environment of over 40 Torr using SiH4 gas; forming a tungsten seed layer on the treated barrier metal layer using WF6 and SiH4 gases, a mixing ratio {WF6}/{SiH4} of the gases being less than or equal to one; and forming a tungsten layer on the treated barrier metal layer using WF6 gas, the treated barrier metal layer having the tungsten seed layer formed thereon.