In this work we studied titanium silicide formation by cosputtering onto silicon dioxide. Samples deposited with various (Si/Ti) atomic ratios were analyzed by Rutherford Backscattering Spectrometry (RBS). Isocronal annealings were conducted by means of Rapid Thermal Processing (RTP) in two types of furnaces: a vacuum and an atmospheric pressure (argon). Phase formation was monitored by resistivity measurements, X-Ray diffraction (XRD), and Scanning Electron Microscopy (SEM). It is observed that the final phase formation follows the thennodynamic equilibrium diagram, determined by stoichiometry, occurring at 800°C for the vacuum furnace, and at 900°C for the atmospheric RTP furnace. Sequential thermal treatments indicated the formation of TiSi2-C49 and/or TiSi after 400°C.