METHOD FOR FABRICATING CAPACITOR OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for fabricating a capacitor of a semiconductor device is provided to reduce resistance by forming a concave pad instead of a conventional buried contact plug, and to prevent a bridge phenomenon by disposing the lower surface of a lower electrode inside a buried contact hole. CONSTITUTION: A pad interlayer dielectric is formed on a semiconductor substrate(101). The pad interlayer dielectric is patterned to form the buried contact hole(117) exposing a predetermined region of the semiconductor substrate. A conformal pad conductive layer is formed on the substrate including the inside of the buried contact hole. A sacrificial insulation layer filling the buried contact hole is formed on the pad conductive layer. The sacrificial insulation layer and the pad conductive layer are planarized until the pad interlayer dielectric is exposed, so that the concave pad(118a) and a sacrificial insulation layer pattern are formed. An etch barrier layer(120) and a mold insulation layer are sequentially formed on the concave pad and the sacrificial insulation layer pattern. The mold insulation layer, the etch barrier layer and the sacrificial insulation layer pattern are continuously patterned to form a lower electrode hole exposing the concave pad. A lower electrode layer is formed on the substrate including the inside of the lower electrode hole. The lower electrode layer is separated to form a cylindrical lower electrode(123a). The concave pad is formed of a conductive layer having etch selectivity to the sacrificial insulation layer pattern.