Magnetic Metal Films on Semiconductor Substrates
Magnetic Metal Films on Semiconductor Substrates
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DOI：
10.1007/3-540-27166-x_1
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
G. A. Prinz
中科院分区：
文献类型：
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作者：
G. A. Prinz
在过去的十年中，磁性金属薄膜的兴趣增长是巨大的，这两卷中的主题显示。这是由于1980年代出现了三种不同的发展趋势。首先，超高真空技术的发展，仔细生长和表征单晶衬底上的单晶薄膜。这一领域通常被称为“分子束外延”，这是从半导体界接管的术语。虽然对于元素金属膜的沉积不严格适用，但是该术语在磁性金属膜社区中被广泛使用和接受，因为沉积源、程序、技术以及实际上”MBE机器”本身本质上是相同的。[See分子束外延技术讨论的附录]。第二个发展是研究这些新材料的自旋极化电子技术。这些都引起了一个词汇的”自旋极化”前缀名称，如自旋极化光电发射，自旋极化电子能量损失谱，自旋极化电子显微镜等，这些主题的详细讨论，在第一卷。最后，超级计算机的出现使计算物理学取得了相当大的进展，特别是在有限厚度的单晶磁性金属板的电子结构的直接计算方面。因此，这个循环是封闭的，原子尺度的结构可以生长，表征和modeled.Most外延磁性金属薄膜的实验工作都集中在单晶金属衬底上，而不是在半导体衬底上的生长。原因有两方面。首先，在几种元素磁性金属晶体结构和几种元素非磁性金属之间存在非常好的晶格匹配，所述元素非磁性金属可以容易地以适合用作衬底的单晶形式获得。它们分别是Cu、Ag和Au上的Fe、Co和Ni。具体晶体结构及其晶格常数见表1.1。到目前为止，“工业”的“主力”是Cu，但Ag也被广泛用于研究bcc Fe。第二个原因是经济和文化两方面的。大部分工作是由来自表面的研究人员进行的：科学界，通常在大学里，对他们来说，测量技术主导了实验（如光电发射或电子散射）。在这种环境下，必须最大限度地减少在材料准备上花费的时间和精力。此外，样品通常永远不会离开实验室。一个给定的衬底被一遍又一遍地使用，
Over the past decade, the growth of interest in magnetic metal films has been enormous, as the topics in these two volumes show. This stems from three different developments which converged during the 1980s. First, ultra high vacuum techniques were developed to carefully grow and characterize single crystal films on single crystal substrates. This field has come to be generally called" Molecular Beam Epitaxy", a term taken over from the semiconductor community. Although not strictly true for the deposition of elemental metal films, the term is nevertheless widely used and accepted in the magnetic metal film community, since the deposition sources, procedures, techniques and indeed the" MBE machines" themselves, are essentially the same.[See Appendix for a discussion of MBE techniques]. The second development was in spinpolarized electron techniques to study these new materials. These have given rise to a lexicon of" Spin-polarized" prefixed names, such as spin-polarized photoemission, spin-polarized electron energy loss spectroscopy, spin-polarized electron microscopy, etc. These topics are discussed in detail in Volume I. Finally, the advent of the supercomputers permitted considerable progress in computational physics and specifically in the direct calculation of the electronic structure of single crystal magnetic metal slabs of finite thickness. The circle was thus closed and atomic scale structures could be grown, characterized and modeled.Much of the experimental effort on epitaxial magnetic metal films has focused upon growth on single crystal metal substrates rather than on semiconductor substrates. The reasons for this are two-fold. First of all there is a very good lattice match between several elemental magnetic metal crystal structures and several elemental non-magnetic metals which may be readily obtained in single crystal form suitable for use as substrates. These are, respectively Fe, Co and Ni upon Cu, Ag and Au. The specific crystal structures and their lattice constants are given in Table 1.1. By far, the" workhorse" of the" industry" is Cu, but Ag is also widely used for studying bcc Fe. The second reason is both economic and cultural. Much of the work is carried out by researchers from the surface: science community, often in universities, for'whom the measurement techniques dominate the experiment (such as photoemission or electron scattering). In this environment, the time and effort spent on material preparation must be minimized. Furthermore, the sample generally never leaves the experimental chamber. A given substrate is used over and over, merely sputtered