METHOD FOR FORMING GATE ELECTRODE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a gate electrode of a semiconductor device is provided to form a grain having a proper size by performing a rapid thermal heat treatment process in two steps. CONSTITUTION: A gate oxide layer(15) is deposited on a semiconductor substrate(10). Then, a gate electrode(20) consisting of a tungsten layer, a tungsten nitride layer and a polysilicon layer is formed on the gate oxide layer(15). After depositing a tungsten nitride layer, the first heat-treating process is carried out in a predetermined temperature thereby growing a grain size. After that, the second heat-treating process is carried out by increasing the temperature so that the grain of the tungsten nitride layer is recrystallized. The first heat-treating process is carried out in the temperature less than 800°C.