Thin films of ZrNx were prepared by reactive rf magnetron sputtering from a Zr target in an At + N-2 atmosphere, with different substrate biases (zero to -200 V) and nitrogen flow ratios (0.5%-24%). The resistivity, density, stoichiometry, and crystal structure of ZrNx films were investigated. With 2% of nitrogen flow ratio, all ZrNx films exhibit the cubic ZrN crystal phase, regardless of the magnitude of substrate bias. The zero-biased ZrNx film contains substantial oxygen and shows high resistivity. Once a negative bias is applied to the substrate, the incorporated oxygen in ZrNx films can be reduced and the (111)(ZrN) preferred orientation is enhanced. Resistivity as low as 67 muOmega cm can be attained with -200 V of substrate bias. At -200 V of substrate bias, all films show the ZrN phase when the nitrogen flow ratio varies from 0.5% to 24%. However, the nitrogen content in ZrNx films increases continuously with the increasing nitrogen flow ratio. Resistivity of ZrNx films first decreases (0.5%-2%), and then increases with increasing nitrogen flow ratio (2%-24%). The best resistivity is obtained for the ZrNx film sputtered with 2% of nitrogen flow ratio and this sample exhibits the optimum grain size, (111)(ZrN) prefer orientation, density, and stoichiometry. The connection among the resistivity, density, stoichiometry, and crystal structure of ZrNx films and how they are influenced by the sputtering conditions (substrate bias, nitrogen flow ratio) are discussed. (C) 2004 American Vacuum Society.