We report the growth of thin films of ferromagnetic Heusler alloy Co2TiSn on Si (100) substrate using KrF excimer pulsed laser ablation. Films of thicknesses ranging from 8 to 220 nm were deposited on Si (100) substrate heated up to 200 +/- 10 degrees C, with an aim to study the structural, morphological and magnetic properties. The grown films are off-stoichiometric, polycrystalline, having single-phase with high degree of (220) texturing. Angle dependent fluorescence measurements suggest no segregation of alloying elements as a function of depth. X-ray reflectivity measurements indicate that all the films are having low density layer at the top as well as at the film-substrate interface. Magneto optical Kerr effect measurements at room temperature reveal clear hysteresis loops suggesting ferromagnetic behavior of the films. Thermal annealing at temperature >= 220 degrees C suggest transformation of Co2TiSn phase into cobalt silicide phase, which confirms the necessity of low substrate temperature (<220 degrees C) to produce such single-phase Co2TiSn films. (C) 2008 Elsevier B.V. All rights reserved.