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A. Watanabe, Y. Imai, M. Mukaida, K. Osato, T. Kameyama, and K. Fukuda
[Proc. 1st. Int. Conf. on Processing Materials for Properties, p.1245, 1993]
Tantalum oxide films were prepared by KrF excimer laser chemical vapor deposition under various partial pressures (0.4-3.2 mTorr) of Ta(OCH_{3})_{5} and various laser repetition rates (20-120 Hz) at the fixed laser fluence (=450 Jm^{-2}) and the total pressure (=1 Torr) with coexisting helium gas. Deposits with the XRD patterns corresponding to Ta_{2}O_{5} have been obtained though the chemical shift of Ta 4f core electron levels measured by X-ray photoelectron spectroscopy suggests a formation of non-stoichiometric oxides. The (1 -1-1 0) planes are preferentially oriented parallel to the substrate surfaces under the conditions of relatively high supersaturation of the photolytically decomposed monomer, while the (1 -1-1 1) planes of the deposits are under the conditions of lower supersaturation. A correlation between the preferential orientation of specified crystal plane and the supersaturation of the monomer was discussed in terms of Pangarov's crystal growth model.