METHOD FOR FABRICATING BURIED WORD LINE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a buried word line of a semiconductor device is provided to prevent the degradation of threshold voltages by controlling the loss of a gate dielectric layer in a recess process of a conductive layer. CONSTITUTION: A recess groove(101) is formed on a semiconductor substrate(100). An oxide layer(200) is formed on a surface of the recess groove. A metal layer filling the recess groove is formed. A buried word line(410) is formed by etching back the metal layer by using the plasma of an etching gas, a helium gas, and an oxygen gas for the metal layer.