摘要
Amorphous NbN x O y C z films were deposited on SiO by metallorganic chemical vapor deposition using ethylimidotris(diethylamido)niobium(V) [NEt=Nb(NEt 2 ) 3 ] source with and without ammonia (NH 3 ) at various temperatures. The diffusion barrier properties of NbN x O y C z films for Cu metallization were investigated. Both deposition temperature and resistivity of the film was found to decrease drastically upon the addition of NH 3 . The activation energy for the surface reaction was measured to be 0.71±0.05 eV in the temperature range of 500-600 °C and decreased to 0.23±0.04 eV by adding 20 sccm NH 3 in the temperature range of 300-425 °C. The NbN x O y C z films were found to be nearly amorphous. The concentration of C in films was reduced significantly and the concentration ratio of N to Nb was varied from 1.67 to 1.1 by using NH 3 as a reactant gas. Fifty nanometer-thick NbN x O y C z film was found to effectively prevent the penetration of Cu into the substrate in samples annealed at 600 °C for 1 h. The barrier failure mechanism in NbN x O y C z is the diffusion of Cu through the barrier layer with the formation of niobium silicide. © 2002 Elsevier Science B.V. All rights reserved.