PUB - Publikationen an der Universität Bielefeld

Magnetic tunnel junctions were prepared by deposition of a Ta-buffered Fe-AlOx-Fe trilayer on a thermally oxidized silicon wafer. In order to investigate the influence of different Fe oxides like a spinel-like phase and a spinel (Hycernite) on the tunneling magnetoresistance effect, a Fe-57 tracer was deposited at the lower barrier interface. Using conversion electron Mossbauer spectroscopy the evolution of chemical, structural, and magnetic changes in the tracer was monitored starting from the as-prepared state and after several annealing steps. The nuclear probe technique enables to resolve phase formation at the interface with submonolayer resolution. (c) 2006 American Institute of Physics.