Titanium nitride (TiN) films were synthesized at ambient temperature on (1 0 0) silicon substrates by a filtered vacuum cathodic arc source and simultaneous bombardment from nitrogen ion beam. The effects of N ion energy on the film morphology, composition, microstructure, resistivity and mechanical properties were systematically investigated. With increasing N ion energy, the film was initially composed of many small spiky grains separated by deep boundaries, and then of many domed grains isolated by shallow boundaries, and finally of far smaller and much more spiky grains with the deepest boundaries. The chemical composition did not vary much with the ion energy. Increasing N ion energy also resulted in the change of the film phase composition and texture, where the competition between the strain energy and the stopping energy determined the film orientation. As the ion energy increased, the film resistivity increased while the film hardness decreased. The films possessed adhesion property independent of N ion energy and superior to that of the films deposited by magnetron sputtering. Some explanation will be given in detail. (C) 2003 Elsevier Science B.V. All rights reserved.