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近代的科学技术对半导体材料的性能不断地提出新的要求,最初发現的一些半导体材料已經显得不够了。为了寻找新的半导体材料,必須有科学的預見性。这里首先要解决的問題是什么样的物貭才具有半导体性貭,也就是說要弄清物貭結构和电学性质的关系;紧跟着的問題是如何估計半导体的重要参数(如禁带寬度和載流子迁移率)。解决了上述問題,我們就有了寻找的方向,从而少走弯路。在解释物貭的半导体性貭上,以量子力学为基础而建立的能带論获得了很大成就。但是能带論是有局限性的。首先,能带論是以晶体結构的长程序作为出发点,不能預言具有何种組成的物质有半导体性质;其次,近年来发現不少玻璃态和液态半导体,用品体长程序的周期性很难解释;另外,卽使組成最简单的半导体其能带結构也需要相当繁杂的計算才能得出来。
Modern science and technology continue to put forward new requirements on the performance of semiconductor materials. Some of the semiconductor materials originally discovered are not enough. In order to find new semiconductor materials, there must be scientific predictability. The first question to be solved here is what kind of thing is semiconducting, that is to say, to understand the relationship between the structure and the electrical properties of objects; the question is how to estimate the important parameters of the semiconductor (such as forbidden band width And carrier mobility). Solve the above problems, we have to find the direction, so less detours. In interpreting the semiconducting properties of objects, the energy band theory based on quantum mechanics has been greatly successful. However, band theory is limited. First of all, band theory is based on the crystal structure of the long process as a starting point, can not predict what kind of composition has the semiconductor properties of semiconductors; Second, in recent years found that many glassy and liquid semiconductors, In addition, 卽 the simplest composition of the semiconductor energy band structure also need a very complicated calculation can be drawn.