Back Cover: Epitaxial upward transport of Al at the beginning of the Al-induced layer exchange process (Phys. Status Solidi RRL 5-6/2011)

Abstract

The Rapid Research Letter by Birajdar et al. on pp. 172–174 reports on the Al transport during the early stage of Al-induced layer exchange (ALILE) and crystallization reaction, a promising process for the fabrication of polycrystalline Si films to be used in thin film transistors and solar cells. The authors report that not only vertical but also lateral redistribution of Al occurs during the ALILE and crystallization reaction. This yields Al deficient dendritic cell centers surrounded by an about 10 μm wide Al excess zone containing epitaxial islands of “pushed-up” Al whose number density and size decrease with increasing distance from the reaction front as illustrated in the Al elemental map acquired in the transmission electron microscope. The corresponding sketches in the cross-section geometry are shown on the right.