US Patent 7651909 Method for fabricating metal-insulator-metal capacitor

A method for fabricating a metal-insulator-metal capacitor is described. A first metal layer is formed on a substrate. A plasma treatment is performed on the surface of the first metal layer. Then, a first oxide layer, a nitride layer and a second oxide layer are formed in sequence over the first metal layer. Thereafter, a second metal layer is formed on the second oxide layer. The second metal layer, the second oxide layer, the nitride layer, the first oxide layer and the first metal layer are defined to form the metal-insulator-metal capacitor.