METHOD FOR REDUCING TUNGSTEN FILM ROUGHNESS AND IMPROVING STEP COVERAGE

摘要

PURPOSE: A method for reducing tungsten film roughness and enlarging a step coverage is provided to add nitrogen to a processing gas flow, thereby reducing tungsten film roughness and enlarging a step coverage. CONSTITUTION: A semiconductor substrate is arranged on a deposition chamber(301). The semiconductor substrate is heated up to a temperature required for forming a tungsten core(303). The temperature for forming a core is between 200 and 475°C. A thin tungsten core forming layer is formed on the semiconductor substrate(305). A tungsten bulk layer is formed on the core forming layer(307).