FeNiCrSiB/Cu/FeNiCrSiB膜的磁畴结构和巨磁阻抗效应

DOMAIN STRUCTURE AND GIANT MAG- NETOIMPEDANCE EFFECTS OF FeNiCrSiB/Cu/FeNiCrSiB FILMS

用高频溅射法制备了ＦｅＮｉＣｒＳｉＢ／Ｃｕ／ＦｅＮＩＣｒＳｉＢ膜，经３５０℃退火２０ ｍｉｎ后得到性能优良的巨磁阻抗材料．磁畴结构观察表明，样品中心为均匀的细条畴，靠近边缘，磁畴方向转向横向．这种畴结构有利于磁力线的闭合，是获得显著的巨磁阻抗效应的重要原因之一。磁阻抗测量表明，样品在１３ＭＨｚ的频率下，分别获得了６３％和７７％的纵向和横向磁阻抗比。

Fe Ni CrSiB/Cu/FeNiCrSiB sandwiched films have been prepared by RF sputtering. After annealing at 350℃ for 20 min, the films show excellent giant magnetoimpedance (GMI) effect. The observations of domain structure show that the fine and homogeneous stripe domains are obtained at the central area, and they turn to the transverse direction at the edge area. This kind of domain structures is favourable to the closed magnetic flux loop, and is one of the important reasons obtained notable GMI effect. GMI measurements show that GMI ratio as large as 63% and 77% were obtained at 13 MHz in the longitudinal and transverse fields, respectively.