Studies Of Giant Magneto-Impedance Effect In Sandwiched Film

The Sandwiched films manifest notable GMI effect in low frequency value; and high sensitivity, small volume, fast response are better than GMR effect. It will be important for application of high-tec sensor.In this thesis, NiFeSiMoMn/Cu/NiFeSiMoMn sandwiched films including Wcu =0.3mm 0.7mm and 0.9mm have been prepared by DC magnetron sputtering deposition and including Wcu = 0.3mm 0.5mm 0.7mm and 0.9mm by vacuum evaporated deposition.. As a result. 2.5 u m 12.5 u m /2.5 u m by DC magnetron sputtering deposition and 1um/lum/1um by vacuum evaporated deposition sandwiched films have been successfully prepared.The relations of GMI effect and extra magnetical field driving frequency the width of copper were studied for both of two kinds of sample. In addition, we also studied the relation of permeability and extra magnetical field for sputtering sample.Large GMI value have been obtairied from the samples without annealing.The lognitudinal GMI value of sputtering samples manifestied the maximal 15.4% at Hex = Hk = 5 Oe and transverse GMI maximal value is 6.63% at zero field when optimal driving frequency equaled 3.3MHz and 4MHz respectively. The real part of longitudinal permeability occurs double peaks and transverse permeability occurs simple peak. The imaginary part of both of them occur simple peak.The permeability of sputtering samples are better than evaporating samples.The lognitudinal GMI value of evaporating samples manifestied the maximal 4.23 %and transverse GMI maximal value is 0.78 % at zero field at Hev = Hk = 10 Oe when driving frequency equaled 5MHz.The GMI value of them exhibited oscillatory variation by the change of copper width; High sensitivity of GMI effect is "AB" in both samples. The optimal driving frequenc> of sputtering samples is lower than evaporating samples. The Hk for sputtering samples is lower than evaporating samples.The GMI effect of sputtering samples is better than evaporating samples.