Characteristics of amorphous tungsten nitride diffusion barrier for metal-organic chemical vapor deposited Cu metallization

Abstract

Copper thin films are deposited on amorphous' tungsten nitride diffusion barrier by metalorganic chemical vapor deposition method. The resistivity of Cu film is considerably higher than those of Cu films deposited on SiO,, borophospho-silica glass, and Si due to substratedriven reaction. RBS, XTEM and XRD measurements clearly show that 100-800 A amorphous W,N,, layer successfully executes the role of diffusion barrier for Cu during the annealing process at 800 OC for 30 min.