AFM and Optical Studies of Boron Nitride and Graphene Grown By High Temperature Molecular Beam Epitaxy

高温分子束外延生长氮化硼和石墨烯的 AFM 和光学研究

• 批准号: 2884050
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2884050
• 关键词: AFM; Optical; Studies; Boron; Nitride

Hexagonal boron nitride (hBN) can be used as an insulating barrier layer on other 2D materials such as graphene or as a semiconductor with a 6 eV band gap [1]. In most research the hBN is exfoliated from bulk crystals using adhesive tape and transferred to other substrates. We have been investigating the growth of hexagonal boron nitride and graphene by high temperature molecular epitaxy for several years [2]. The aim is to grow hBN in a way that is scalable to allow controlled heterostructures of hBN and graphene (for instance) to be grown.At present our focus is on understanding how dopant atoms such as carbon are incorporated into the hexagonal boron nitride and affect the growth of the layers. We use atomic resolution atomic force microscopy (AFM), spectroscopic ellipsometry and confocal fluorescent microscopy to study the structure and optical response of the layers. For example, at low carbon doping we have identified single photon emitters that have previously been proposed as being related to carbon impurities [3] and at high carbon doping we can see the formation of impurity bands in the spectroscopic ellipsometry signatures. We also collaborate with several groups internationally [e.g. refs 1 and 3 ] to make additional measurements e.g. fluorescence study in the deep UV.The PhD student in this project will be responsible for measuring and analysing the samples using high resolution ambient AFM, confocal microscopy and spectroscopic ellipsometry. For the confocal microscopy experiments there is scope to further develop the instrumentation and to study other types of defects e.g. boron vacancies that appear to be very stable, can act as single photon emitters and are candidate materials for local sensing of magnetic fields [4].References1. C. Elias, et al, (2019) Nature Communications 10, 26392. Y.J. Cho, et al, (2016) Scientific Reports 6, 344743. N. Mendelson, et al, (2021) Nature Materials 20, 3214. H.L. Stern, et al, (2022) Nature Communications 13, 618

六角硼硝酸盐（HBN）可以用作其他2D材料（例如石墨烯）或具有6 eV带隙的半导体上的绝缘屏障层[1]。在大多数研究中，HBN使用胶带从散装晶体中删除，并转移到其他底物上。几年来，我们一直在研究高温分子外延的六角硼和石墨烯的生长[2]。目的是以可扩展的方式生长HBN，以允许HBN和石墨烯的受控异质结构（例如）进行种植。目前，我们的重点是了解如何将碳（例如碳）掺入六边形的硝酸氢烷硝基硼中并影响层的生长。我们使用原子分辨率原子力显微镜（AFM），光谱椭圆法和共聚焦荧光显微镜来研究层的结构和光学响应。例如，在低碳掺杂下，我们已经确定了以前提出的单个光子发射器，这些光子发射器与碳杂质有关[3]，在高碳掺杂下，我们可以在光谱椭圆法签名中看到杂质带的形成。我们还与国际上的几个小组合作[例如参考文献1和3]进行其他测量，例如该项目的PhD学生在深紫外线中进行荧光研究，将负责使用高分辨率环境AFM，共聚焦显微镜和光谱椭圆法测量和分析样品。对于共聚焦显微镜实验，有范围可以进一步发展仪器并研究其他类型的缺陷，例如似乎非常稳定的硼空缺可以充当单个光子发射器，并且是磁场局部传感的候选材料[4]。参考1。 C. Elias等人，（2019年）自然通信10，26392。Y.J。Cho等，（2016）科学报告6，344743。N。Mendelson等人，等等，（2021）Nature Materials 20，3214。H.L. Stern等