SEMICONDUCTOR DEVICE HAVING A BURIED GATE PATTERN INCLUDING HIGH-K DIELECTRIC CAPPING LAYER AND FABRICATING METHOD THEREOF

摘要

PURPOSE: A semiconductor device with a buried gate pattern including a high-k dielectric protection film pattern and a manufacturing method thereof are provided to form a low dielectric material film on a high dielectric material film to decrease electric fields in source/drain areas, thereby preventing leaked currents. CONSTITUTION: A gate trench is formed on a substrate(10). A buried gate electrode(16) partially fills the gate trench. A protection film pattern(20a) is formed in the gate trench. Source/drain areas(22,24) are formed under the surface of the substrate adjacent to both sides of the buried gate electrode. A gate insulating film(18a) is interposed between the trench and the buried gate electrode.