Effect of a thin Ta layer on the C49-C54 transition

The effect of a thin Ta layer at the Ti/Si interface on the kinetics of the C49-C54 transition is reported. The transformation kinetics were monitored in detail by in situ sheet resistance measurements, which, coupled to stru ctural characterisation, allowed us to evidence the presence of an intermed iate phase before C54 formation. The temperature at which the C53 phase is formed decreases at a Ta concentration of 4.5 X 10(15) cm(-2). mu -Raman im ages of partially transformed samples indicates that the density of C54 gra ins in the presence of Ta is about one order of magnitude higher with respe ct to pure Ti/Si samples. (C) 2001 Elsevier Science BN. All rights reserved .