METHOD FOR FABRICATING GATE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a gate of a semiconductor device is provided to form a dual gate having a pair of metals of the same kind, by forming a metal nitride layer having a work function different from that of the first metal layer in either one of an n-type metal oxide semiconductor(NMOS) or p-type metal oxide semiconductor(PMOS) region. CONSTITUTION: A semiconductor substrate(11) is prepared in which a dummy gate is formed on the PMOS region(13b) and the NMOS region(13a), respectively. An interlayer dielectric(20) is deposited on the semiconductor substrate. The interlayer dielectric is polished until the dummy gate on the substrate is exposed. The dummy gate is exposed to expose a predetermined portion of the substrate including the PMOS and NMOS regions. A gate insulation layer and the first metal layer(22) are sequentially deposited on the substrate including a region where the dummy gate is removed. A nitrogen containing process is performed regarding either one of the NMOS or PMOS region where the first metal layer is formed so that the first metal layer is nitridized. The second metal layer is formed on the resultant structure. The second metal layer, the first metal layer, the nitridized first metal layer(22a) and the gate insulation layer are sequentially eliminated until the interlayer dielectric is exposed.