We report a preliminary survey of the effects of dc substrate bias and residual gas contamination on the average composition, internal stress, electrical conductivity, and crystal structure of molybdenum films deposited by rf sputtering. We find strong interrelations among all these parameters. Thus films sputtered in residual pressure approximately 10−5 Torr exhibit stress changing from tensile to compressive with increasingly negative bias, passing through neutrality at about −15 V. Quantitative analysis, however, reveals that stress relief is attained only at the expense of the incorporation of large (30 at.%) amounts of oxygen and nitrogen. This in turn substantiates the attribution of the fcc structure observed in such films to a MoNx phase rather than a new polytype of Mo. Deposition at lower residual pressure with floating bias results in bcc structure, negligible gas incorporation, closer approach to bulk conductivity, but compressive stress. These results suggest the necessity for compromise in the choice of deposition parameters for practical applications.