Patent ID: 8405188

Claim:
A semiconductor device, comprising: a semiconductor substrate; and a ferroelectric capacitor including a lower electrode, a ferroelectric film formed on the lower electrode, and an upper electrode formed on the ferroelectric film, over the semiconductor substrate, wherein the upper electrode includes a first layer formed of a first oxide expressed by a chemical formula AO x1 (A: metal element, O: oxygen) using a stoichiometric composition parameter x 1 and expressed by a chemical formula AO x2 using an actual composition parameter x 2 , a second layer formed of a second oxide having a thickness of 125 nm to 150 nm, formed on the first layer, expressed by a chemical formula BO y1 (B: metal element, O: oxygen) using a stoichiometric composition parameter y 1 and expressed by a chemical formula BO y2 using an actual composition parameter y 2 , in which a ratio of oxidation is set higher than the first layer, and a third layer formed on the second layer and formed of one of noble metal, alloy including noble metal, and oxide of one of noble metal and alloy including noble metal, wherein a relation y 2 /y 1 >x 2 /x 1 is satisfied between the composition parameters x 1 , x 2 , y 1 , y 2 , and a thickness of the first layer is thinner than a thickness of the second layer.