By comparing the spatial distribution of Ti atom density in front of a planar substrate with a diffusion model proposed by Chantry [P. J. Chantry, J. Appl. Phys. 62, 1141 (1987)], the authors evaluated the sticking probability of Ti atoms in magnetron sputtering deposition. The spatial distribution of Ti atom density was measured precisely by laser-induced fluorescence imaging spectroscopy. They found that the sticking probability of Ti atoms during the growth of Ti film was 0.9 +/- 0.2. This result suggests the possibility that the sticking probability is less than unity, which is widely assumed in many simulation studies. The sticking probability was almost unchanged when the discharge pressure and power were varied. In addition, heating the substrate at 250 degrees C and biasing it at a self-bias voltage of -200 V by a rf power had no significant influence on the sticking probability. (c) 2007 American Vacuum Society.