[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 [SiO]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
Ferroelectric materials were widely applied for actuators and sensors. Barium zirconate titanate Ba(Zr0.25Ti0.75)O3 thin film was grown on Pt/Ti/SiO2/Si(100) substrates by pulsed laser deposition. Structure and surfac...Ferroelectric materials were widely applied for actuators and sensors. Barium zirconate titanate Ba(Zr0.25Ti0.75)O3 thin film was grown on Pt/Ti/SiO2/Si(100) substrates by pulsed laser deposition. Structure and surface morphology of the thin film were studied by X-ray diffractometry(XRD) and scan electronic microscopy(SEM). The composition and chemical state near the film surface were obtained by X-ray photoelectron spectroscopy(XPS). On the sample surface,O 1s spectra can be assigned to those from the lattice and surface adsorbed oxygen ions,while C1s only result from surface contamination. The result shows that only one chemical state is found for each spectrum of Ba 3d,Zr 3d and Ti 2p photoelectron in the BZT thin film.展开更多
Graphene on dielectric substrates is essential for its electronic applications. Graphene is typically synthesized on the surface of metal and then transferred to an appropriate substrate for fabricating device applica...Graphene on dielectric substrates is essential for its electronic applications. Graphene is typically synthesized on the surface of metal and then transferred to an appropriate substrate for fabricating device applications. This post growth transfer process is detrimental to the quality and performance of the as-grown graphene. Therefore, direct growth of graphene films on dielectric substrates without any transfer process is highly desirable. However, fast growth of graphene on dielectric substrates remains challenging. Here, we demonstrate a transfer-free chemical vapor deposition (CVD) method to directly grow graphene films on dielectric substrates at fast growth rate using Cu as floating catalyst. A large area (centimeter level) graphene can be grown within 15 min using this CVD method, which is increased by 500 times compared to other direct CVD growth on dielectric substrate in the literatures. This research presents a significant progress in transfer-free growth of graphene and graphene device applications.展开更多
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 [SiO]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Project(05001825) supported by Guangdong Provincial Natural Science Foundation of Chinaproject(KF0707) supported by the Opening Project Program of Key Laboratory of Low Dimensional Materials and Application Technology (Xiangtan University), Ministry ofEducation, China
文摘Ferroelectric materials were widely applied for actuators and sensors. Barium zirconate titanate Ba(Zr0.25Ti0.75)O3 thin film was grown on Pt/Ti/SiO2/Si(100) substrates by pulsed laser deposition. Structure and surface morphology of the thin film were studied by X-ray diffractometry(XRD) and scan electronic microscopy(SEM). The composition and chemical state near the film surface were obtained by X-ray photoelectron spectroscopy(XPS). On the sample surface,O 1s spectra can be assigned to those from the lattice and surface adsorbed oxygen ions,while C1s only result from surface contamination. The result shows that only one chemical state is found for each spectrum of Ba 3d,Zr 3d and Ti 2p photoelectron in the BZT thin film.
基金supported by the National Natural Science Foundation of China (61390502, 51502059, 61172001, 21373068)the National Basic Research Program of China (2013CB632900)+3 种基金the Foundational Research Funds for the Central Universities (HIT. NSRIF.201641)Self-Planned Task (SKLRS201509B) of State Key Laboratory of Robotics and System (HIT)China Postdoctoral Science Foundation Grant (2015M570285)Heilongjiang Provincial Postdoctoral Science Foundation Grant (LBH-Z15053)
文摘Graphene on dielectric substrates is essential for its electronic applications. Graphene is typically synthesized on the surface of metal and then transferred to an appropriate substrate for fabricating device applications. This post growth transfer process is detrimental to the quality and performance of the as-grown graphene. Therefore, direct growth of graphene films on dielectric substrates without any transfer process is highly desirable. However, fast growth of graphene on dielectric substrates remains challenging. Here, we demonstrate a transfer-free chemical vapor deposition (CVD) method to directly grow graphene films on dielectric substrates at fast growth rate using Cu as floating catalyst. A large area (centimeter level) graphene can be grown within 15 min using this CVD method, which is increased by 500 times compared to other direct CVD growth on dielectric substrate in the literatures. This research presents a significant progress in transfer-free growth of graphene and graphene device applications.
