Nanometer-Scale interface stracture of epitaxially-grown metallic multilayrs and their electronic properties

用分子束沉积法在Si（111）（7 × 7）衬底上生长了Pt/Co金属多层膜（铁磁金属Co和贵金属Pt的组合）和作为多层膜基本单元的Pt薄膜，并对衬底状态、晶体生长、表面形貌、膜的亚结构以及Cu缓冲层的作用进行了研究。这对多层膜的外延生长有很大影响。利用扫描隧道显微镜、原子力显微镜和透射电子显微镜研究了Cu/Si的界面结构，结果表明：（i）Cu/Si界面形成了均匀的Cu硅化物，（ii）Pt膜在深度方向上保持单晶，以及（iii）Pt膜不具有任何针孔并且保持高质量。采用分子束沉积方法，在超高真空洁净气氛下，在Si衬底上外延生长了Pt/Co多层膜。在Pt/Co多层膜的晶体生长过程中，Pt/Co和Co/Pt都是赝象的，因此Pt/Co多层膜内部含有弹性应变，表现出良好的上级垂直磁各向异性.界面引起的电阻率增加是多层膜内部的65%。

Pt/Co metallic multilayrs, a combination of a ferromagnetic metal Co and a noble metal Pt, and Pt thin films, as a fundamental unit of the multilayrs, were grown on Si (111) (7x7) substrate by molecular beam deposition method, and were studied about state of the substrate, crystal growth, surface topograph, inferior structure of the films, and role of Cu buffer layr, which give a great influence on epitaxial growth of the multilayrs. Interface structures are also studied on nanometer-scale, and the relations between such the structures and electronic properties were discussed.The studies with scanning tunneling microscopy, atomic force microscopy and transmission electron microscopy show that (i) Cu silicides are formed uniformly at Cu/Si interface, (ii) the Pt film keeps a single crystal in the depth direction, and (iii) the Pt film dose not have any pin hole and maintains high quality. It is concluded that the Pt films are suitable for a seeded layr.A Pt/Co multilayr was successfully grown epitaxially on the Si substrate with the Pt seeded layr and the Cu buffer layr by molecular beam deposition method under clean atmosphere of ultra-high vacuum condition. On crystal growth of the Pt/Co multilayr, both Pt on Co and Co on Pt are pseudomorphic, and hence Pt/Co multilayr contained elastic strain inside and showed superior perpendicular magnetoanisotropy.As to study on electronic properties of the Pt films and the Pt/Co multilayr, surface and interface effects in the electron transport are evaluated using a simulated model of electronic circuit. Increase of electrical resistivity induced by the interface was 65% of interior of multilayr.