CRYSTALLOGRAPHIC ORIENTATION AND MAGNETIC ANISOTROPY IN COBALT/NOBLE METAL MULTILAYERS AND ALLOY FILMS

（100）取向衬底上Co/Pt和Co/Au多层膜的结构和磁各向异性：（100）取向Pt和Au衬底在（100）取向NaCl衬底上以300℃的温度外延生长。在（100）取向Pt衬底上蒸发的Co/Pt多层膜具有（100）取向fcc结构，在30 ~ 400‰的温度范围内与Ts无关。在没有衬底加热的情况下，面外磁各向异性为负，但随着衬底温度的升高而增加。这表明界面处Co-Pt合金的形成增强了面外磁各向异性。接下来，Co/Au多层膜在（100）取向的Au衬底上蒸发，温度为Ts=100 C。我们无法通过x射线衍射测量来确定其结构。然而，电子衍射测量表明（100）取向fcc Co和（11.0）取向hcp Co在Co层中共存。面外磁各向异性是负的，与钴层厚度无关。在Co/Pt和Co/Au层中均可见到四重对称的面内磁各向异性，这可能归因于fcc Co和/或hcp Co的磁晶各向异性。(2)Co-Pt和Co-Au合金薄膜在（100）取向Ag衬底上溅射的结构和磁各向异性：（100）取向Ag衬底在（100）取向NaCl衬底上成功溅射。在（100）取向银衬底上溅射Co-Pt和Co-Au合金薄膜。当Pt含量大于40%时，（100）取向Co-Pt合金薄膜在（100）取向Ag衬底上外延生长。相反，无论Au含量如何，Co-Au薄膜中都没有观察到择优取向。无论Co-Pt和Co-Au薄膜的成分如何，其平面磁各向异性都是负的。（100）取向Co-Pt合金薄膜具有四重对称的面内磁各向异性。

Structure and magnetic anisotropy of Co/Pt and Co/Au multilayrs evaporated on (100) -oriented underlayr : (100) -oriented Pt and Au underlayrs were epitaxially grown on a (100) -oriented NaCl substrate at a substrate temperature (Ts) of 300ﾟC.Co/Pt multilayrs evaporated on a (100) -oriented Pt underlayr are of (100) -oriented fcc structure independent of Ts from 30 to 400ﾟC.Out-of-plane magnetic anisotropy is negative without substrate heating but increases with elevating substrate temperature. This suggests that the formation of Co-Pt alloy at interface enhances out-of-plane magnetic anisotropy. Next, Co/Au multilayrs were evaporated on a (100) -orinted Au underlayr at Ts=100ﾟC.We could not identify the structure through X-ray diffraction measurements.However, electron diffraction measurements revealed that (100) -orinted fcc Co and (11.0) -oriented hcp Co coexist in the Co layr. Out-of-plane magnetic anisotropy is negative irrespective of Co layr thickness. In both Co/Pt and Co/Au multilayrs was seen in-plane magnetic anisotropy with four-fold symmetry, which seems to be ascribable to the magneto-crystalline anisotropy of fcc Co and/or hcp Co.(2) Structure and magnetic anisotropy of Co-Pt and Co-Au alloy films sputtered on (100) -oriented Ag underlayr : (100) -oriented Ag underlayrs were successfully sputtered on a (100) -oriented NaCl substrate without substrate heating. Co-Pt and Co-Au alloy films were sputtered on a (100) -orinted Ag underlayr. (100) -oriented Co-Pt alloy films were epitaxially grown on a (100) -oriented Ag underlayr, provided that the Pt content was higher than 40%.On the contrary, no preferential orientation was observed in Co-Au films irrespective of the Au content. Our-of-plane magnetic anisotropy is negative irrespective of the composition in both Co-Pt and Co-Au films. In-plane magnetic anisotropy with four-fold symmetry was seen in (100) -oriented Co-Pt alloy films.