FePt/Ag thin films were deposited by magnetron sputtering onto 7059 glass substrates, then were annealed at 550 ℃ for 30 min. Nanostructured FePt/Ag films were successfully obtained with the magnetic easy axis of L10...FePt/Ag thin films were deposited by magnetron sputtering onto 7059 glass substrates, then were annealed at 550 ℃ for 30 min. Nanostructured FePt/Ag films were successfully obtained with the magnetic easy axis of L10 FePt perpendicular to the film plane. It was found that the development of （001） texture depended strongly on the thicknesses of FePt magnetic layer and Ag underlayer. The L10 ordered FePt（15 nm）/Ag（50 nm） with （001） orientation can be obtained. And the perpendicular coercivity of FePt（15 nm）/Ag（50 nm） film reached to 7.2× 10^5 A/m, whereas the longitudinal one was only 3.2×10^4 A/m. The non-magnetic Ag underlayer can not only induce （001） orientation and ordering of FePt grains, but also reduce the intergrain interactions.展开更多
The Fe/Pt multilayer films with different structures were deposited by RF magnetron sputtering on glass substrates, and the L10-FePt films were obtained after the asdeposited samples were subjected to vacuum annealing...The Fe/Pt multilayer films with different structures were deposited by RF magnetron sputtering on glass substrates, and the L10-FePt films were obtained after the asdeposited samples were subjected to vacuum annealing at various temperatures. Results show that the Fe/Pt multilayer structure can effectively reduce the ordering temperature of FePt film, and the in-plane coercivity of [Fe （5.2 nm）/Pt （5.2 nm）]7 multilayers can reach 161.2 kA/m after annealed at 350℃ for 30 min. When Fe and Pt layer thickness is equal, the coercivity of the film is the largest. On the other hand, the different Fe-Pt crystalline phases such as Fe3Pt and FePt3 phases are formed after annealing when the thickness ratio of Fe/Pt deviates from 1 after annealing. When Fe and Pt have the same thickness, the thinner single layer gets the lower ordering temperature and the larger coercivity.展开更多
[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied...[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied to study the magnetic properties and microstructures of the films. The results show that without Ag underlayer [SiO2/FePt]5 films deposited onto the glass are FCC disordered; with the addition of Ag underlayer [SiO2/FePt]5/Ag films are changed into L10 and (111) mixed texture. The variation of the SiO2 nonmagnetic layer thickness in [SiO2/FePt]5/Ag films indicates that SiO2-doping plays an important role in improving the order parameter and the perpendicular magnetic anisotropy, and reducing the grain size and intergrain interactions. By controlling SiO2 thickness the highly perpendicular magnetic anisotropy can be obtained in the [SiO2 (0.6 nm)/FePt (3 nm)]5/Ag (50 nm) films and highly (001)-oriented films can be obtained in the [SiO2 (2 nm)/FePt (3 nm)]5/Ag (50 nm) films.展开更多
FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin...FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin films, effects of Ag addition on the structure and properties of FePt thin films were investigated. Proper Ag addition was found helpful for FePt phase transition at lower annealing temperature. With Ag addition, the magnetic domain pattern of FePt thin film changed from maze-like pattern to more discrete island-like domain pattern in [FePt/Ag]n multilayer thin films. In addition, introducing nonmagnetic Ag hindered FePt grains from growing larger. The in-depth defects in FePt films and [FePt/Ag]n multilayer films verify that Ag addition is attributed to a large number of pinning site defects in [FePt/Ag]n film and therefore has effects on its magnetic properties and microstructure.展开更多
FePt films with a high degree of order S of the L10 structure （S 〉 0.90） and well defined [001] crystalline growth perpendicular to the film plane are fabricated on thermally oxidized Si substrates by the addition ...FePt films with a high degree of order S of the L10 structure （S 〉 0.90） and well defined [001] crystalline growth perpendicular to the film plane are fabricated on thermally oxidized Si substrates by the addition of ZnO and a successive rapid thermal annealing （RTA） process. The optimum condition to prepare high-ordering L10 FePtZnO films is 20 vol% ZnO addition and 450 ℃ annealing. The effect of the ZnO additive on the ordering process of the L10 FePtZnO films is discussed. In the annealing process, Zn atoms move to the film surface and evaporate. The motion of the Zn atoms accelerates the intergrain exchange and decreases the ordering temperature.展开更多
The monolayer film of FePt nanoparticles with the mean size about 4 nm was fabricated on a silicon substrate by the Langmuir-Blodgett(LB) technology. The properties of the monolayer film were characterized by π-A iso...The monolayer film of FePt nanoparticles with the mean size about 4 nm was fabricated on a silicon substrate by the Langmuir-Blodgett(LB) technology. The properties of the monolayer film were characterized by π-A isotherms, atomic force microscope(AFM) and small-angle X-ray diffraction. The results showed that the monolayer of FePt nanoparticles has a smooth surface and a dense structure as shown by the AFM image. Small-angle X-ray diffraction(SXRD) measurement of multilayer structure for the FePt nanoparticles indicated that the superlattices consist of well-defined smooth layers.展开更多
基金supported by the National Natural Science Foundation of China(Grant No:10274018)the Foundation of Hebei Provincial Education Department(Grant No:002013)the Key Foundation of Hebei Normal University(Grant No:120203).
文摘FePt/Ag thin films were deposited by magnetron sputtering onto 7059 glass substrates, then were annealed at 550 ℃ for 30 min. Nanostructured FePt/Ag films were successfully obtained with the magnetic easy axis of L10 FePt perpendicular to the film plane. It was found that the development of （001） texture depended strongly on the thicknesses of FePt magnetic layer and Ag underlayer. The L10 ordered FePt（15 nm）/Ag（50 nm） with （001） orientation can be obtained. And the perpendicular coercivity of FePt（15 nm）/Ag（50 nm） film reached to 7.2× 10^5 A/m, whereas the longitudinal one was only 3.2×10^4 A/m. The non-magnetic Ag underlayer can not only induce （001） orientation and ordering of FePt grains, but also reduce the intergrain interactions.
基金supported by the National Natural Science Foundation of China(No.60571010)Natural Science Foundation of Hubei province.
文摘The Fe/Pt multilayer films with different structures were deposited by RF magnetron sputtering on glass substrates, and the L10-FePt films were obtained after the asdeposited samples were subjected to vacuum annealing at various temperatures. Results show that the Fe/Pt multilayer structure can effectively reduce the ordering temperature of FePt film, and the in-plane coercivity of [Fe （5.2 nm）/Pt （5.2 nm）]7 multilayers can reach 161.2 kA/m after annealed at 350℃ for 30 min. When Fe and Pt layer thickness is equal, the coercivity of the film is the largest. On the other hand, the different Fe-Pt crystalline phases such as Fe3Pt and FePt3 phases are formed after annealing when the thickness ratio of Fe/Pt deviates from 1 after annealing. When Fe and Pt have the same thickness, the thinner single layer gets the lower ordering temperature and the larger coercivity.
基金Project(10574085) supported by the National Natural Science Foundation of ChinaProject(207020) supported by the Science Technology Key Project of the Ministry of Education, China
文摘[SiO2/FePt]5/Ag thin films were deposited by RF magnetron sputtering on the glass substrates and post annealing at 550 ℃ for 30 min in vacuum. Vibrating sample magnetometer and X-ray diffraction analyser were applied to study the magnetic properties and microstructures of the films. The results show that without Ag underlayer [SiO2/FePt]5 films deposited onto the glass are FCC disordered; with the addition of Ag underlayer [SiO2/FePt]5/Ag films are changed into L10 and (111) mixed texture. The variation of the SiO2 nonmagnetic layer thickness in [SiO2/FePt]5/Ag films indicates that SiO2-doping plays an important role in improving the order parameter and the perpendicular magnetic anisotropy, and reducing the grain size and intergrain interactions. By controlling SiO2 thickness the highly perpendicular magnetic anisotropy can be obtained in the [SiO2 (0.6 nm)/FePt (3 nm)]5/Ag (50 nm) films and highly (001)-oriented films can be obtained in the [SiO2 (2 nm)/FePt (3 nm)]5/Ag (50 nm) films.
基金the National Natural Science Foundation of China (No. 60571010)the Open Foundation of the Key Laboratory of Ferroelectric and Piezoelectric Materials and Devices of Hubei Province in Hubei University
文摘FePt thin films and [FePt/Ag]n multilayer thin films were prepared by magnetron sputtering technique and subsequent annealing process. By comparing the microstructure and magnetic properties of these two kinds of thin films, effects of Ag addition on the structure and properties of FePt thin films were investigated. Proper Ag addition was found helpful for FePt phase transition at lower annealing temperature. With Ag addition, the magnetic domain pattern of FePt thin film changed from maze-like pattern to more discrete island-like domain pattern in [FePt/Ag]n multilayer thin films. In addition, introducing nonmagnetic Ag hindered FePt grains from growing larger. The in-depth defects in FePt films and [FePt/Ag]n multilayer films verify that Ag addition is attributed to a large number of pinning site defects in [FePt/Ag]n film and therefore has effects on its magnetic properties and microstructure.
文摘FePt films with a high degree of order S of the L10 structure （S 〉 0.90） and well defined [001] crystalline growth perpendicular to the film plane are fabricated on thermally oxidized Si substrates by the addition of ZnO and a successive rapid thermal annealing （RTA） process. The optimum condition to prepare high-ordering L10 FePtZnO films is 20 vol% ZnO addition and 450 ℃ annealing. The effect of the ZnO additive on the ordering process of the L10 FePtZnO films is discussed. In the annealing process, Zn atoms move to the film surface and evaporate. The motion of the Zn atoms accelerates the intergrain exchange and decreases the ordering temperature.
文摘The monolayer film of FePt nanoparticles with the mean size about 4 nm was fabricated on a silicon substrate by the Langmuir-Blodgett(LB) technology. The properties of the monolayer film were characterized by π-A isotherms, atomic force microscope(AFM) and small-angle X-ray diffraction. The results showed that the monolayer of FePt nanoparticles has a smooth surface and a dense structure as shown by the AFM image. Small-angle X-ray diffraction(SXRD) measurement of multilayer structure for the FePt nanoparticles indicated that the superlattices consist of well-defined smooth layers.
