In this paper we show the use of a nondestructive method, thermal-wave imaging, for characterizing the formation of titanium disilicide. We indicate that it is possible to have information on its structure. The observation of thermal-wave signals and images allows us to recognize the metastable C49 phase and the equilibrium C54 phase of the disilicide. The thermal-wave topographic signals and images give information on the stability of the titanium disilicide after deposition and thermal annealing of low pressure chemical vapor deposition tetraethylorthosilicate oxide.