The diffusion of silicon from an underlying silicon substrate into a Ti film has been investigated as a function of the annealing temperature and time of a Rapid Thermal Annealer, using Auger spectroscopy. It was found that at 600°C, silicide formation is initiated witin 10 sec. and the thickness of the silicide formed increased approximately as the square root of time, at this temperature. The rate of silicide formation is higher than that ex-pected from the kinetics obtained for conventional diffusion furnace anneals. It was found that the interfacial native oxide between the Ti and Si greatly affected both the kinetics of silicide formation and the quality of the film. By using a high dose (1x1016 ions/cm2) heavy ion implantation through the Ti film (ion beam mixing) the interfacial oxide could be dispersed. As a consequence, for a given temperature and time of anneal, the ion-beam mixed films show more silicide formed than a non ion-beam mixed film. Also, the ion-mixed films retained a smooth surface and interface after annealing.
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