Improved magnetization in sputtered dysprosium thin films

50 nm thick nanogranular polycrystalline dysprosium thin films have been prepared via ultra-high vacuum direct-current sputtering on SiO2 and Si wafers. The maximum in-plane spontaneous magnetization at T = 4 K was found to be μ0MS,4K(C)=(3.28±0.26) T for samples deposited on wafers heated to 350 °C with a Néel point of TN(C)=(173±2) K and a ferromagnetic (FM) transition at TC(C)=(80±2) K, measured via zero-field-cooled–field-cooled magnetization measurements, close to single-crystal values. The slightly reduced magnetization is explained in the light of a metastable face-centred cubic crystal phase which occurred at the seed interface and granularity related effects that are still noticeably influential despite an in-plane magnetic easy axis. As deposited samples showed reduced magnetization of μ0MS,4K(A)=(2.26±0.18) T, however their FM transition shifted to a much higher temperature of TC(A)=(172±2) K and the antiferromagnetic phase was completely suppressed probably as a result of strain. (fast track communication)