METHOD FOR MANUFACTURING BURIED GATE IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a buried gate of a semiconductor device is provided to prevent the deterioration of a gate insulation layer due to fluorine by using metal organic source without fluorine as source gas when a tungsten containing nitride layer is deposited. CONSTITUTION: A trench(26) is formed by etching a semiconductor substrate(21). A gate insulation layer(27) is formed on the surface of a trench. A tungsten containing nitride layer(28A) with nitrogen concentration gradient is formed on the gate insulation layer. A first tungsten layer(29) is formed on the surface of the tungsten containing nitride layer by removing nitrogen. A second tungsten layer(30) is formed on the first tungsten layer to fill the trench.