Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8042253 | Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms | 2013 | 15 Pages |
Abstract
The displacement of atoms in a magnetic trilayer Fe (10Â nm)/Cr (0.7Â nm)/Fe (10Â nm) system by 30Â keV Ga+ ion irradiation was studied by 3D Atom Probe Tomography (APT). From APT, the positions of individual Cr and Fe atoms could be located with sub-nm spatial resolution, both before and after ion bombardment. In the pristine specimen the presence of the 0.7-nm Cr layer was identified and individual lattice planes with a distance of â¼0.15Â nm were observed which would correspond to the monolayer spacing of the Fe lattice, in agreement with the growth process. Upon irradiation, the Cr layer broadens to â¼1.2Â nm at a fluence of 3Â ÃÂ 1014Â Ga+/cm2 and to â¼3.4Â nm at 3Â ÃÂ 1015Â Ga+/cm2. From this broadening the mean squared relocation distance of (Cr) atoms was derived, ãr2ã â¼0.4Â nm2. Computer simulations indicate that, at a fluence of 3Â ÃÂ 1014Â Ga+/cm2, each Cr atom in the intermediate layer is displaced on average once in the collision processes. The distribution of implanted Ga ions appears to exhibit discontinuities at the Fe/Cr interfaces which might be caused by a demixing of Ga at the Cr layer.
Related Topics
Physical Sciences and Engineering
Materials Science
Surfaces, Coatings and Films
Authors
Hubert Gnaser, Rüdiger Schiller, Michael Wahl, Bernhard Reuscher,