This article reports electron field-emission measurements on hydrogenated amorphous carbon [diamond-like carbon (DLC)] films grown by aspirating CH4+N2 gas mixtures into a saddle field fast atom beam source. The electron field-emission behavior of these films is discussed in light of varying power, substrate bias, nitrogen dilution, and film thickness. Specifically, changes in the residual stress and hardness of these films are also estimated. The threshold field (Eturn ON) for electron emission shows a minimum at 3.5 V/μm in DLC films grown with 32 W power applied to the source, which is further reduced to 2.7 V/μm, when a positive bias of 100 V is applied to the substrates. Nitrogen dilution of the feedstock is found to reduce the Eturn ON further and it shows a minimum at 2.4 V/μm at ∼27% nitrogen dilution beyond which the value of Eturn ON is found to increase. Emission current density of ∼1 mA/cm2 has been observed at 4.7 V/μm in these nitrogenated DLC films (at ∼27% nitrogen dilution). Further it has been found that Eturn ON increases with the increase of thickness of DLC films since there also appears to be a correlation between the residual stress of these films and Eturn ON values. Better field-emission behavior is observed in those DLC films which recorded lower values of residual stress. © 2003 American Vacuum Society.