Effect of a thin ionized-metal-plasma deposited Cu layer on the properties and thermal stability of Cu-TaN-SiO/sub 2/-Si structures

Cu-TaN-SiO/sub 2/-Si structures, fabricated in a three-in-one system, were systematically investigated using various techniques. By depositing a thin plasma-metal-plasma (IMP) Cu layer on the TaN barrier prior to the copper film deposited using metal-organic chemical vapor deposition, the sheet resistance, uniformity, and adhesion of the metal in the Cu-TaN-SiO/sub 2/-Si structures can be significantly improved. The thermal stability of the structures can also be enhanced due to the reduction of Cu diffusion and out-diffusion of Si, Ta, and O elements. These observations are of great value for application of chemical vapor deposition Cu-IMP Cu in multilevel interconnects of deep-submicron integrated circuits.