摘要
With RF sputtering process, Si/Si02/Ta/Ru/Ta/CoFeB/MgO/CoFeB/Ta/Ru structure has been grown on Si (100) substrate. Attempting different targets and adjusting the oxygen dose, the crystallization quality of the MgO layer is studied. The X-ray diffraction measurements demonstrate that crystal structure and crystallization quality of MgO layers are related to the type of target and concentration of oxygen in sputtering process. With the method sputtering Mg in an ambient flow of oxygen, not only the crystallization quality of a normal MgO layer with lattice constant of 0.421 nm is improved, but also a new MgO crystal with lattice constant of 0.812 nm is formed and the perpendicular magnetic anisotropy of CoFeB is enhanced. Also it is found that crystallization quality for both the normal MgO and new MgO is more improved with MgO target and same oxygen dose, which means that this new method is helpful to form a new structure of MgO annealed at 400 ℃ in vacuum. with lattice constant of 0.812 nm. All of the samples were
With RF sputtering process, Si/Si02/Ta/Ru/Ta/CoFeB/MgO/CoFeB/Ta/Ru structure has been grown on Si (100) substrate. Attempting different targets and adjusting the oxygen dose, the crystallization quality of the MgO layer is studied. The X-ray diffraction measurements demonstrate that crystal structure and crystallization quality of MgO layers are related to the type of target and concentration of oxygen in sputtering process. With the method sputtering Mg in an ambient flow of oxygen, not only the crystallization quality of a normal MgO layer with lattice constant of 0.421 nm is improved, but also a new MgO crystal with lattice constant of 0.812 nm is formed and the perpendicular magnetic anisotropy of CoFeB is enhanced. Also it is found that crystallization quality for both the normal MgO and new MgO is more improved with MgO target and same oxygen dose, which means that this new method is helpful to form a new structure of MgO annealed at 400 ℃ in vacuum. with lattice constant of 0.812 nm. All of the samples were
基金
Project supported by the National Defense Advance Research Foundation(No.9140A080040410DZ106)
the Basic Research Program of Ministry of Education,China(No.JY10000925005)
the Scientific Research Program Funded by Shaanxi Provincial Education Department(No.11JK0912)
the Scientific Research Foundation of Xi’an University of Science and Technology(No.2010011)
the Doctoral Research Startup Fund of Xi’an University of Science and Technology(No.2010QDJ029)