Kinetic shape formation during Gd thin film and Si(100) solid phase reaction

The initial stage of the solid phase reaction between gadolinium thin film and Si(100) substrate was investigated by x-ray diffraction and scanning el ectron microscopy. The interdiffusion was retarded by deliberate contaminat ion of the Gd/Si interface to slow down the extremely rapid reaction. The s urface of the reacted film showed pattern formation in separate spots. The fractal-like development of this rare-earth silicide indicates a kinetic-ty pe process-modified by the structure of the Gd film and by the emerging str esses-rather than a previously proposed nucleation-controlled growth. (C) 1 999 American Institute of Physics. [S0003-6951(99)00112-6].