半导体光电材料中的缺陷和掺杂调控  

Defect physics and doping engineering in semiconductor optoelectronic materials

作　　者：郭丹 杨凯科 邓惠雄 Dan Guo;Kaike Yang;Huixiong Deng(State Key Laboratory of Superlattices and Microstructures,Institute of Semiconductors,Chinese Academy of Sciences,Beijing 100083,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院半导体研究所,超晶格国家重点实验室,北京100083 [2]中国科学院大学材料科学与光电工程中心,北京100049

出　　处：《科学通报》2020年第28期3185-3193,共10页Chinese Science Bulletin

基　　金：国家自然科学基金优秀青年科学基金(61922077);中国科学院青年创新促进会(2017154)资助。

摘　　要：半导体材料在集成电路、光伏发电、信息通讯、微电子器件、照明等领域发挥着重要作用,已成为半导体学科研究的重要方向.然而,半导体材料的掺杂和缺陷调控能力在很大程度上制约着半导体器件的性能.本文首先回顾了半导体掺杂和缺陷计算理论的发展,阐述了传统的凝胶电荷模型方法的弊端和局限性.为了克服这一弊端,我们提出了一个严格的、统一的理论,即转移真实态模型.该模型可以直接计算三维及低维半导体的带电缺陷性质.其次,讨论了宽禁带半导体发展所面临的困难.通过分析掺杂极限定律,针对氧化物宽禁带半导体,介绍了行之有效的缺陷设计准则和调控方法,并用来提高p型半导体的导电率.再次,讨论了非晶态宽禁带半导体中离子化合物与共价化合物导电性差异的物理机制,以及低维宽禁带半导体赝氢钝化和真实氢钝化的差异原理.从次,分析了高浓度掺杂形成的半导体合金.由于带边波函数的局域性,异价半导体合金不满足统计平均规律,揭示出大失配同价高浓度掺杂能带交叉的物理原理.最后,聚焦金属杂质在半导体中的扩散现象,阐明了银和铜原子在离子半导体和共价半导体中扩散差异性的根本原因.Semiconductor materials play a central role in the integrated circuits, photovoltaics, information and communication,microelectronic devices, lighting, and so on. However, the performance of semiconductor optoelectronic devices depends critically on the dopability and defect engineering of semiconductor materials. In this paper, firstly, we introduce the doping properties in semiconductors and the theoretical progress of charged defect calculations over the past decades, including the traditional jellium model. To overcome the disadvantages and limitations of the traditional jellium model, recently, we propose a straightforward and universal theory, i.e., transfer real state model(TRSM), which can calculate directly the charged defect properties in both bulk and low-dimensional semiconductors. In the jellium model for a finite supercell size calculation, it suffers a serious problem to determine the defect properties in low-dimensional semiconductors due to charge distribution in the vacuum region. However, our TRSM method by putting the ionized electrons or holes on a real host band edge states naturally keeps the supercell neutral and provides clear physical meaning. For three-dimensional bulk materials, the defect formation energy and transition energy level calculated by our TRSM method are almost the same as the results obtained by using the traditional jellium model. For low dimensional semiconductors, however, the TRSM method cures the divergence issue that occurred in the jellium model due to long-range electrostatic Coulomb interactions.Secondly, we discuss the wide band gap semiconductors. By analyzing the doping limit law, we elucidate the effective methods for defect engineering in oxide wide band gap semiconductors, and then how their p-type conductivity can be improved. Those methods are based on two rules:(1) Reducing the ionization energy of acceptors;(2) suppressing the formation of compensating donors. Further, the physical mechanism of the difference in conductivity between ionic and covalent c

关 键 词：半导体 缺陷 掺杂 合金 扩散 

分 类 号：TN304[电子电信—物理电子学]