Kinetics and moving species during Co₂Si formation by rapid thermal annealing

We have investigated the growth kinetics and identified the moving species during Co₂Si formation by rapid thermal annealing (RTA). For the kinetics study, samples which consisted of a thin Co film on an evaporated Si substrate were used. To study which species moves, samples imbedded with two very thin Ta markers were employed. Upon RTA, only one silicide phase, Co ₂Si, was observed to grow before all Co was consumed. The square root of time dependence and the activation energy of about 2.1±0.2 eV were observed during the Co₂Si formation up to 680 °C. The marker study indicated that Co is the dominant mobile species during Co₂Si formation by RTA. We conclude that Co₂Si grows by the same mechanisms during RTA and conventional thermal annealing.