| AVS 59th Annual International Symposium and Exhibition | |
| Thin Film | Thursday Sessions |
| Session TF-ThP |
| Session: | Thin Film Poster Session |
| Presenter: | H.F. Kirby, University of South Florida |
| Authors: | H.F. Kirby, University of South Florida D.D. Belyea, University of South Florida J.T. Willman, University of South Florida C.G. Hendryx, Newsome High School C.W. Miller, University of South Florida |
| Correspondent: | Click to Email |
The effects of deposition temperature, post-deposition annealing, and chamber gettering were investigated on the magnetocaloric properties in Ta(5nm)/Gd(30nm)/Ta(5nm) grown by magnetron sputtering. The magnetocaloric effect (MCE) in these thin films, as indicated by the magnetic entropy change around the ordering temperature, increases with both growth temperature and post-deposition annealing of samples grown under ambient conditions. The full width at half max of the entropy change peak generally decreased toward the value for bulk Gd with increasing deposition and annealing temperature. Similarly, the temperature of the maximum entropy change increased toward the bulk Gd ordering temperature. Overall the relative cooling power increased as deposition and annealing temperatures were increased. Gettering proved useful in limiting oxidation of the Gd especially for high temperature growth: ungettered samples grown at 600°C were purely diamagnetic GdO (111), while gettered samples, though still containing some GdO, were ferromagnetic.