Thin films sputtered from Ba2NdFeNb4O15 multiferroic targets on BaFe12O19 coated substrates

Abstract

Ba2NdFeNb4O15 tetragonal tungsten bronze (TTB) / BaFe12O19 (BaM) hexaferrite bilayers have been grown by RF magnetron sputtering on Pt/TiO2/SiO2/Si (PtS) substrates. The BaM layer is textured along (00l) while the TTB layer is multioriented regardless of the PtS or BaM/PtS substrate. Dielectric properties of TTB films are similar to those of bulk, i.e.,  ~ 150 and a magnetic hysteresis loop is obtained from TTB/BaM bilayers, thanks to the BaM component. This demonstrates the possibility of transferring to 2 dimensional structures the composite multiferroic system TTB/BaM previously identified in 3 dimensional bulk ceramics.

Dependence of the Structural and Magnetic Properties on the Growth Sequence in Heterostructures Designed by YbFeO3 and BaFe12O19

“…In Figure 4b, we assume that the mass densities of the substrate YSZ as well as of the YbFO and BaM layers are constant as they are limited by short dashed vertical lines. Furthermore, the mass densities of the targets BaFe 12 O 19 , YbFeO 3 , and YSZ(111) are given by ρ BaFe12O19 = 5.296 g/cm 3 , ρ YbFeO3 = 6.8 g/cm 3 , and ρ YSZ = 5.92 g/cm 3 , respectively, and are drawn by the horizontal gray dashed lines in Figure 4b. The transition regions which correspond to the interfaces with the YSZ(111) substrate (i.e., BaM/YSZ for M2 and YbFO/YSZ for M1) and between the bilayers (BaM/YbFO for M1 and YbFO/BaM for M2) are highlighted by green and gray rectangles to be investigated with higher magnification for the thickness x-axis scale in Figure 4c.…”

“…Different devices were recently produced by combining barium ferrite BaFe 12 O 19 (BaM) with ferroelectric materials to form multiferroic systems with magneto-electric coupling at the well-defined and characterized interface in terms of sharpness, atomic step, and chemical interdiffusion. It has covered thin-film heterostructures such as SrBa 2 Ta 2 O 9 /BaM [ 1 , 2 ], Ba 2 EuFeNb 4 O 15 /BaM [ 3 , 4 ], multilayers composed of BaM layers with Pb(Zr,Ti)O 3 (PZT) [ 5 ] or (Ba,Sr)TiO 3 (BST) [ 6 , 7 , 8 ] or BaTiO 3 perovskite layers [ 9 ], and multiferroic composites [ 10 , 11 , 12 ]. BaM is a very attractive material due to the high anisotropy H a and coercivity H C fields [ 13 , 14 ], which are beneficial for obtaining performant film in perpendicular recording media.…”

Фазовый состав, кристаллическая структура, диэлектрические и сегнетоэлектрические свойства тонких пленок Ba-=SUB=-2-=/SUB=-NdFeNb-=SUB=-4-=/SUB=-O-=SUB=-15-=/SUB=-, выращенных на подложке Si(001) в атмосфере кислорода

“…В слу-чае тонких пленок, как известно, важную роль играет не только метод их синтеза, но также механизм роста и структурное совершенство [7], что в настоящее время в случае сегнетоэлектриков и мультиферроиков анализируется редко. Как показал анализ литературы, пленки Ba 2 LnFeNb 4 O 15 к настоящему времени получены главным образом несколькими промышленно используемыми методами: импульсно-лазерным напылением [8], магнетронным распылением [9] и совершенствуемым нами методом ВЧ-катодного распыления [10,11].…”

Obtaining, crystal structure and nanostructure of Ba2NdFeNb4O15 heteroepitaxial films fabricated by RF sputtering on MgO(001) substrates

“…The partial replacement of Nd ions by Pr ions leads to the appearance of relaxor properties in the BNFNO [16]. The BNFNO in the form of nanosized films obtained only in 2016 on the MgO (001), STO (001) and Si (001) substrates [18][19][20][21]. The appearance of orientation domains with a rotation of the film axes relative to the substrate by ±18.4°was found in BNFNO on STO substrate, while in the case of MgO substrate there are both ±18.4°and ±31°domains.…”