Molecular-beam epitaxy of group III nitride-based dilute magnetic semiconductors

III族氮化物基稀磁半导体的分子束外延

• 批准号: 40997750
• 负责人: Dr. Achim Trampert
• 金额: --
• 依托单位: Paul-Drude-Institut für Festkörperelektronik (PDI)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2007
• 资助国家: 德国
• 起止时间: 2006-12-31 至 2009-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/40997750?language=en
• 关键词: Molecular; beam; epitaxy; group; III

Dilute magnetic semiconductors are considered as potential candidates for realizing spininjection or spin-alignment in semiconductor heterostructures. We have recently found that Gd-doped GaN shows ferromagnetism at room temperature. The atomistic mechanism for this magnetic ordering is not yet completely understood, although theoretical considerations have predicted high Curie temperatures values in dilute magnetic wide bandgap semiconductors. The project will deals with the growth of ferromagnetic Gd-doped group-III nitrides by molecular beam epitaxy (MBE) and the study of the structure-property relation. A main focus is on the realization of dilute magnetic semiconductors in comparison to granular materials that include small clusters of second-phases. Because epitaxial nitride films are highly defective, we will in detail investigate the effect of the crystalline perfection on the magnetic properties by using different substrate materials for the MBE. Furthermore, Gd-doped GaN and AlN layers reflecting high electric resistivity are used to investigate the potential of codoping with Si and Mg in order to realize n- and p-type conductivity and the effect on the magnetic behaviour.

稀磁半导体被认为是在半导体异质结构中实现自旋注入或自旋取向的潜在候选者。我们最近发现Gd掺杂的GaN在室温下显示出铁磁性。这种磁有序的原子机制尚未完全理解，尽管理论上已经预测了稀磁宽带隙半导体的高居里温度值。本计画将利用分子束磊晶技术成长掺钆第三族氮化物之铁磁性材料，并研究其结构与性质之关系。一个主要的重点是实现稀磁半导体相比，颗粒状材料，包括小集群的第二相。由于外延氮化物薄膜是高度缺陷的，我们将详细研究的结晶完整性的影响，通过使用不同的衬底材料的MBE的磁性能。此外，Gd掺杂的GaN和AlN层反映高电阻率被用来调查的潜力，共掺杂Si和Mg，以实现n型和p型导电性和对磁行为的影响。