Magnetic properties improvement of Co-Cr-Ta alloy target materials by annealing

We addressed the problem of ferromagnetic Co-Cr-Ta alloy target with low pass through flux (PTF) in synthesis of high density storage thin films by magnetron sputtering. A novel technique (annealing in argon) was developed to fabricate high PTF Co-Cr-Ta alloy target. The impacts of the annealing temperature and time on the microstructures, phases, and PTF, were evaluated X-ray diffraction and differential scanning caliorimetry. The preliminary results show that the annealing significantly affects its surface PTF, bulk texture, microstructures, and phase structures. For example, an increased annealing time resulted in a higher PTF. Annealed under the optimized conditions, the domiant Co-phase changed from bcc into hcp with textures aligned parallel to the rolled target surface, and its PTF incereased by 5 times, We suggest that the phase transition and formation of {12 10} and {10 10} line-textures may account for the PTF enhancement.