Ni 0.81Fe 0.19) 0.66Cr 0.34 has a high resistivity and a crystal structure close to that of Ni 0.81Fe 0.19.The electrical and X-ray diffraction measurements prove that a thin NiFeCr seed layer induce...Ni 0.81Fe 0.19) 0.66Cr 0.34 has a high resistivity and a crystal structure close to that of Ni 0.81Fe 0.19.The electrical and X-ray diffraction measurements prove that a thin NiFeCr seed layer induces a well (111)-oriented Ni 0.81Fe 0.19 film.Post-annealing treatment improves the magnetic properties of (Ni 0.81Fe 0.19) 0.66Cr 0.34(45?)/Ni 0.81Fe 0.19(150?)/Ta(55?) thin film prepared under a deposition field,whereas the inter-diffusion of NiFe/Ta deteriorates the magnetoresistance properties of the film.展开更多
Permalloy Ni80Fe20 films have been grown on thermal oxidized Si (111) wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 K in 0.65 Pa argon pressure. The base pressure wa...Permalloy Ni80Fe20 films have been grown on thermal oxidized Si (111) wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 K in 0.65 Pa argon pressure. The base pressure was about 1×10-4 Pa. The deposition rate was about 5 nm/min for all the films. The structure of the films was studied using X-ray diffraction, scanning electron microscopy and atomic force microscopy. The composition of the films was analyzed using scanning Auger microprobe. The resistance and magnetoresistance of the films were measured using four-point probe technique. The results show that the content of oxygen in the films decreases gradually with raising substrate temperature. In addition, the surface morphology of the films presents notable change with the increasing of the substrate temperature; the residual gases and defects decrease and the grains have coalesced evidently, and then the grains have grown up obviously and the texture of (111) orientation develops gradually in the growing film. As a result, the resistivity reduces apparently and magnetoresistance ratio increases markedly with raising substrate temperature.展开更多
Permalloy Ni_(80)Fe_(20) films have been grown on thermal oxidized Si (111)wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 Kin 0.65 Pa argon pressure. The base pressur...Permalloy Ni_(80)Fe_(20) films have been grown on thermal oxidized Si (111)wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 Kin 0.65 Pa argon pressure. The base pressure was about 1x10^(-4) Pa. The deposition rate was about 5nm/min for all the films. The structure of the films was studied using X-ray diffraction, scanningelectron microscopy and atomic force microscopy. The composition of the films was analyzed usingscanning Auger microprobe. The resistance and magnetoresistance of the films were measured usingfour-point probe technique. The results show that the content of oxygen in the films decreasesgradually with raising substrate temperature. In addition, the surface morphology of the filmspresents notable change with the increasing of the substrate temperature; the residual gases anddefects decrease and the grains have coalesced evidently, and then the grains have grown upobviously and the texture of (111) orientation develops gradually in the growing film. As a result,the resistivity reduces apparently and magnetoresistance ratio increases markedly with raisingsubstrate temperature.展开更多
In this paper, we report a ferromagnetic resonance study on the permalloy film of submicron sized rectangular arrays prepared by electron beam lithography and the theoretical simulation to the non uniform demagnetiz...In this paper, we report a ferromagnetic resonance study on the permalloy film of submicron sized rectangular arrays prepared by electron beam lithography and the theoretical simulation to the non uniform demagnetizing effect and ferromagnetic resonance data. By theoretical simulation, the magnetization, gyromagnetic ratio and g value of the sample are determined. The theoretical curves of the dependence of the resonance field on the field orientation φ H fit well with the experimental data. When the steady magnetic field is applied near the film normal, a series of additional regular peaks (up to eight ) appeared in the FMR spectrum on the low field side of the main FMR peak. The resonance field of these side peaks decreases linearly with the peak number. The possible physical mechanism of these multiple peaks was discussed.展开更多
The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other ...The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other layer without, and (2) both NiFe layershave anisotropy normal each other. The domain wall migration and magnetization rotation processes in each of NiFe layers could be observed separately. The presence of magnetic anisotropy in the magnetic layer effectively controls the behavior of magnetic domains. Theinteraction between the two NiFe layers of the film could be observed not so strong in the present experiment.展开更多
文摘Ni 0.81Fe 0.19) 0.66Cr 0.34 has a high resistivity and a crystal structure close to that of Ni 0.81Fe 0.19.The electrical and X-ray diffraction measurements prove that a thin NiFeCr seed layer induces a well (111)-oriented Ni 0.81Fe 0.19 film.Post-annealing treatment improves the magnetic properties of (Ni 0.81Fe 0.19) 0.66Cr 0.34(45?)/Ni 0.81Fe 0.19(150?)/Ta(55?) thin film prepared under a deposition field,whereas the inter-diffusion of NiFe/Ta deteriorates the magnetoresistance properties of the film.
文摘Permalloy Ni80Fe20 films have been grown on thermal oxidized Si (111) wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 K in 0.65 Pa argon pressure. The base pressure was about 1×10-4 Pa. The deposition rate was about 5 nm/min for all the films. The structure of the films was studied using X-ray diffraction, scanning electron microscopy and atomic force microscopy. The composition of the films was analyzed using scanning Auger microprobe. The resistance and magnetoresistance of the films were measured using four-point probe technique. The results show that the content of oxygen in the films decreases gradually with raising substrate temperature. In addition, the surface morphology of the films presents notable change with the increasing of the substrate temperature; the residual gases and defects decrease and the grains have coalesced evidently, and then the grains have grown up obviously and the texture of (111) orientation develops gradually in the growing film. As a result, the resistivity reduces apparently and magnetoresistance ratio increases markedly with raising substrate temperature.
基金This work was financially supported by National Natural Science Foundation of China (No.19974005).
文摘Permalloy Ni_(80)Fe_(20) films have been grown on thermal oxidized Si (111)wafers by magnetron sputtering at well-controlled substrate temperatures of 300, 500, 640 and 780 Kin 0.65 Pa argon pressure. The base pressure was about 1x10^(-4) Pa. The deposition rate was about 5nm/min for all the films. The structure of the films was studied using X-ray diffraction, scanningelectron microscopy and atomic force microscopy. The composition of the films was analyzed usingscanning Auger microprobe. The resistance and magnetoresistance of the films were measured usingfour-point probe technique. The results show that the content of oxygen in the films decreasesgradually with raising substrate temperature. In addition, the surface morphology of the filmspresents notable change with the increasing of the substrate temperature; the residual gases anddefects decrease and the grains have coalesced evidently, and then the grains have grown upobviously and the texture of (111) orientation develops gradually in the growing film. As a result,the resistivity reduces apparently and magnetoresistance ratio increases markedly with raisingsubstrate temperature.
文摘In this paper, we report a ferromagnetic resonance study on the permalloy film of submicron sized rectangular arrays prepared by electron beam lithography and the theoretical simulation to the non uniform demagnetizing effect and ferromagnetic resonance data. By theoretical simulation, the magnetization, gyromagnetic ratio and g value of the sample are determined. The theoretical curves of the dependence of the resonance field on the field orientation φ H fit well with the experimental data. When the steady magnetic field is applied near the film normal, a series of additional regular peaks (up to eight ) appeared in the FMR spectrum on the low field side of the main FMR peak. The resonance field of these side peaks decreases linearly with the peak number. The possible physical mechanism of these multiple peaks was discussed.
文摘The microstructure change in thin NiFe/Cu/NiFe films during the magnetization process was observed by the Lorentz electronmicroscopy. TWo types of films were prepared: (1) one NiFe layer with anisotropy and the other layer without, and (2) both NiFe layershave anisotropy normal each other. The domain wall migration and magnetization rotation processes in each of NiFe layers could be observed separately. The presence of magnetic anisotropy in the magnetic layer effectively controls the behavior of magnetic domains. Theinteraction between the two NiFe layers of the film could be observed not so strong in the present experiment.
