Study of fast diffusion species in Sc/Si multilayers by W-based marker analysis

Interdiffusion in periodic Sc/Si multilayers with W-based diffusion markers was studied by cross-section transmission electron microscopy and small angle X-ray diffractometry (SAXD). Formation of amorphous ScSi silicide was observed as a result of solid-state amorphization taking place in the Sc/Si multilayers in the 210–250 °C temperature range. The diffusion-governed growth behavior of the amorphous silicide was revealed. The diffusion marker analysis was applied to determine a ratio of intrinsic diffusion coefficients of scandium and silicon. The diffusion-induced shift of the diffusion markers was measured by SAXD with accuracy better than 0.2 nm. It was determined that the intrinsic diffusion coefficient of Si in amorphous silicide was twenty times higher than the one of Sc.