Real-time RBS of solid-state reaction in thin films

Selected examples of real-time RES are shown to underline the strengths of the technique. Due to the simultaneous depth and compositional profiling ca pabilities of RES it is possible in combination with a linearly ramped heat treatment, to determine both the pre-exponential factor and the activation energy of phase formation from a single sample. Other in situ, real-time t echniques also use linearly ramped temperature anneals but require several different temperature ramps to obtain the same parameters. In inert marker experiments the movement of a thin, inert layer is used to determine the at omic transport during growth. The example shown highlights the advantages o f the real-time RES technique where slight movements of the marker layer ar e significant. Linear reaction kinetics is shown for CrSi2 formation. Two l inear regimes were found. The second regime coincided with unintentional ox idation of the Cr surface. An added advantage of kinetic analysis by real-t ime RES is the fact that in those cases where sample preparation is difficu lt and at times irreproducible, e.g. due to experimental details, the fact that the sample kinetics can be measured from a single sample provide far b etter results. This is illustrated by considering growth kinetics of Ni-Si samples, where the Si had been intentionally doped with oxygen. (C) 2000 El sevier Science B.V. All rights reserved.