Al thermal diffusion in a-Si1-xCx:H thin film studied by XAFS

In this work the local structure around the aluminium atoms, diffused by thermal annealing in a-SiC:H thin films was analyzed by x-ray absorption near edge structure (XANES), aiming to obtain information about the Al ordering after annealing. The thermal annealing of the films was performed in ultra high-vacuum (UHV), in order to avoid Al oxidation. The XANES spectra were obtained in-situ at the Al K-edge (1559 eV), immediately after the annealing process, showing that Al diffusion clearly takes place for carbon rich films. The theoretical simulation of these spectra shows that the Al in carbon rich a-SiC:H has structural order similar to that of c-Al4C3.