SEMICONDUCTOR MEMORY DEVICE AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A semiconductor memory device and a method for manufacturing the same are provided to obtain a low contact resistance between a plug and a lower electrode of a capacitor by preventing diffusion of oxygen. CONSTITUTION: An interlayer dielectric(201) is formed on a lower structure including a MOS transistor. An oxygen diffusion barrier(202) is formed on the interlayer dielectric(201). A capacitor contact hole is formed by etching selectively the oxygen diffusion barrier(202) and interlayer dielectric(201). A plug conductive layer is formed within the contact hole. A Ti layer(205) and a TiN layer(206) are formed on the plug conductive layer. The second TiN layer(207) is formed thereon. A lower electrode(208) of a capacitor is formed on the second TiN layer(207). A dielectric layer(209) and an upper electrode(210) are formed on the lower electrode(208). An interlayer dielectric(211) and a metal line(212) are formed thereon.