Over the last years, several experimental and theoretical studies of diffusion kinetics on the nanoscale have shown that the time evolution (x t kc) differs from the classical Fickian law (kc =0.5). However, all work was based on crystalline samples or models, so far. In this letter, we report on the diffusion kinetics of a thin amorphous Si layer into amorphous Ge to account for the rising importance of amorphous materials in nanodevices. Employing surface sensitive techniques, the initial kc was found at 0.7±0.1. Moreover, after some monolayers of Si dissolved into the Ge, kc changes to the generally expected classical Fickian law with kc =0.5.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)