Optical properties of carbon and carbon nitride films prepared by mass-separated energetic negative carbon and carbon nitrogen ions

Carbon and carbon nitride (CN) films were prepared under:ultrahigh vacuum c ondition;by ion beam deposition using isotopically mass-separated, energeti c (50-400 eV) negative C-12(2)- and (CN-)-C-12-N-14 ions, respectively. The optical properties as well as structures and chemical composition of the f ilms have been characterized and discussed as a function of the kinetic ene rgy of C-2(-) and CN- ions, The structures of carbon and CN films in this s tudy were hydrogen-free amorphous carbon (a-C) like. The N/C composition ra tio of the CN films was N/C similar to 0.4,:although the arrival ratio of N /C was N/C = 1. The CN film properties depended weakly on kinetic energy of CN- ions, while on a-C films there were kinetic energy dependence of C-2(- ) ions of optical constant observed. (C) 1999 American Vacuum-Society. [S07 34-2101(99)13604-2].