X-ray photoelectron spectroscopy study of magnetic tunnel junctions

Abstract

Magnetic tunnel junction ( MTJ) structures were investigated by x-ray photoelectron spectroscopy. The Al layer was overoxidized and the samples were treated by rapid thermal annealing. It was found that the Mn atoms in the exchange-bias layer diffused into the magnetic layer, but did not reach the oxide barrier. Although slightly higher oxygen concentration was observed at the interface between the magnetic layer and the oxide barrier, strong evidence of the oxidized magnetic-layer interface was not found. Our result is consistent with the high tunneling magnetoresistance of MTJs at room temperature. (C) 2005 American Institute of Physics.