Atomic transport in LaAlO3 films on Si induced by thermal annealing

Abstract

LaAl O3 films sputter-deposited on Si were submitted to rapid thermal annealing at 800 and 1000°C. Atomic transport and chemical changes were investigated using ion beam analysis and X-ray photoelectron spectroscopy. Annealing induced La and Al losses or their migration into a newly formed interfacial layer and Si migration into the film. The mechanism of Si incorporation into the film is influenced by the annealing atmosphere. These instabilities were hampered by a thermal nitridation in N H3 at 700°C performed prior to rapid thermal annealing, indicating a possible route for producing a thermally stable La-based high- κ gate dielectric. © 2006 The Electrochemical Society.