Soft Magnetic Thin Films Composed of Ultra Fine Crystallites

铁基纳米晶薄膜的软磁性能：采用溅射法制备了FeHFC薄膜和Fe/FeHFC多层薄膜。FeHFC在制备状态下是无定形的，经过热处理后转变为多晶态。在不热处理的情况下，Fe层仍处于纳米晶态。结果表明，两种薄膜均表现出优异的软磁性能。特别是Fe/FeHFC多层膜，由于铁的浓度较高，具有较好的高磁感应强度。此外。结果表明，在700℃左右的高温下，多层膜的纳米晶态是稳定的。这种稳定性被认为是由于HFC细晶在Fe细晶的边界处析出的钉住效应。Co-Fe/Cu和Co- x /Cu多层薄膜的巨磁阻：研究发现，Co的磁致伸缩与Co的合金元素含量有关，约10%的Fe使多层膜的磁阻增强，比Co/Cu多层膜的磁阻增强更大。此外，我们还成功地减小了Co-Fe/Cu/Co-Fe多层膜的磁阻激发磁场。TbFe_2-B和SmFe_2-B非晶合金的磁致伸缩：高速率溅射法制备的TbFe_2-B和SmFe_2-B非晶合金在低磁场下（200 Oe时约60 × 10^<-6>）极易饱和，磁致伸缩量很大。

Soft Magnetic Properties of Fe Based Nano-Crystalline Thin Films: FeHFC then films and Fe/FeHFC multilayered thin films were prepared by a sputter method. The FeHFC was amorphous in the as-prepared state, while it transformed into the mano-crystalline state by a heat treatment. The Fe layers were in the nano-crystalline state even without heat treatment. As a result, both the films showed excellent soft magnetic properties. Particularly, the Fe/FeHFC multilayers were superior in high magnetic induction, because of the high concentration of Fe. In addition. it was found that the nano-crystalline state in the multilayers was stable up to high temperatures as about 700ﾟC. The stability was thought to be attributed to the pinning effect of the HFC fine crystallites precipitated at the boundaries of Fe fine crystallites.Giant Magnetoresistance in Co-Fe/Cu and Co-X/Cu Multilayered Thin Films: It was found that the magnetostriction depended on the alloying elements into Co and about 10 at% of Fe gave rise to an enhanced magnetoresistance, larger than that of Co/Cu multilayer. Moreover, we succeeded to reduce the magnetic field for exciting magnetoresistance in the new multilayer of Co-Fe/Cu/Co-Fe.Magnetostriction in TbFe_2-B and SmFe_2-B Amorphous Alloys: Huge magnetostrictions saturated easyly in low magnetic fields (about 60 x 10^<-6> at 200 Oe) were obtained in TbFe_2-B and SmFe_2-B amorphous alloys prepared by a high rate sputtermethod.