| The structural and magnetic properties of CoNbZr/SiO₂ multilayer films were investigated. Effects of the surface roughness of SiO₂ layers on the properties of CoNbZr/SiO₂ multilayer films were analyzed. The minimum coercivity 3.73 Oe and the maximum permeability at 100 ㎒ of 1783 was observed in [Co_(89.3)Nb_(6.1)Zr_(4.6) 100 ㎚ / SiO₂ 8 ㎚] multilayer films deposited at 130 W and 2 mTorr for CoNbZr films and 200 W and 2 mTorr(Ar/H₂ 20%) for SiO₂ films. When sputtering gas pressure for SiO₂ films increased from 2 mTorr to 6 mTorr, the optimum thickness of SiO₂ layers increased from 10 ㎚ to 25 ㎚. It is thought that degradation of efficiency of insulation was resulted from increase of surface roughness of SiO₂ layers. Futhermore, by the addition of 20% H₂ gas to sputtering gas, the surface roughness of SiO₂ layers decreased from 7.4 Å to 2.14 Å so that soft magnetic properties were improved. When multilayer was annealed for 90 min at 300℃, we obtained anisotropy field of 14 Oe, permeability at 100 ㎒ of 2800. That is considered that the major factor of annealing effect is both reduction of defects and increase of anisotropy in initial stage, but reduction of defects only in later stage. |
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