SEMICONDUCTOR MEMORY DEVICE HAVING DIELECTRIC LAYER WITH IMPROVED DIELECTRIC AND LEAKAGE CURRENT CHARACTERISTIC AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A semiconductor memory device and a manufacturing method thereof are provided to be capable of simultaneously improving dielectric and leakage current characteristics. CONSTITUTION: A semiconductor memory device is provided with a semiconductor substrate(100), a lower electrode(110) formed on the semiconductor substrate, and a dielectric layer(130) formed on the lower electrode. At this time, the dielectric layer is made of an oxide layer containing titanium and tantalum. At the time, the titanium concentration of the dielectric layer becomes different according to the thickness of the dielectric layer. The semiconductor memory device further includes an upper electrode(140) formed on the dielectric layer. Preferably, a reaction restraining layer(120) is located between the lower electrode and the dielectric layer for restraining the reaction of the dielectric layer.