title: Growth, structure, morphology, and magnetic properties of Ni ferrite films.
abstract: The morphology, structure, and magnetic properties of nickel ferrite (NiFe2O4) films fabricated by radio frequency magnetron sputtering on Si(111) substrate have been investigated as functions of film thickness. Prepared films that have not undergone post-annealing show the better spinel crystal structure with increasing growth time. Meanwhile, the size of grain also increases, which induces the change of magnetic properties: saturation magnetization increased and coercivity increased at first and then decreased. Note that the sample of 10-nm thickness is the superparamagnetic property. Transmission electron microscopy displays that the film grew with a disorder structure at initial growth, then forms spinel crystal structure as its thickness increases, which is relative to lattice matching between substrate Si and NiFe2O4.
authors.affiliation: Key Lab for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, People's Republic of China. jiangchj@lzu.edu.cn.
authors.forename: Chunhui
authors.initials: C
authors.lastname: Dong
authors.forename: Gaoxue
authors.initials: G
authors.lastname: Wang
authors.forename: Dangwei
authors.initials: D
authors.lastname: Guo
authors.forename: Changjun
authors.initials: C
authors.lastname: Jiang
authors.forename: Desheng
authors.initials: D
authors.lastname: Xue