Structural investigations of the C49-C54 transformation in TiSi2 thin films

A detailed analysis of the microstructure of TiSi2 thin films has been perf ormed by X-ray diffraction, transmission electron microscopy (TEM) and Rama n spectroscopy. Samples were obtained by rapid thermal annealing or by anne aling under vacuum in a high-temperature diffraction stage. C49 films obtai ned by rapid annealing give broadened X-ray diffraction profiles that canno t be explained by using simple grain-size considerations. The diffraction p rofiles recorded from C54 films are close to powder patterns. Long annealin g gives films where grain-size is close to film thickness. Some 022 texturi ng is present in C54 films, Raman spectra do not depend on the annealing ty pe. In the C49 series, as film thickness increases, a line-shift towards hi gher wavenumber is detected. In thinner C54 films, a polarization effect su ggesting a possible in-plane preferred orientation has been observed. (C) 2 001 Elsevier Science B.V. All rights reserved.