Investigation of new semiconductor materials for wide band-gap devices

该项目旨在开发新的和增强型宽带隙半导体合金，以期在改进的器件中应用。特别是，我们瞄准了紫外线(UV)发射器，包括那些在水净化和杀菌中有重要应用的深紫外波长范围内的发射器，以及高频大功率晶体管。我们将与晶体生长专家密切合作，特别是诺丁汉大学、名古屋大学、南京大学和法国CNRS-CRHEA的同事。通过外延技术生产的材料，如分子束外延，将由学生使用先进的技术来表征，这些技术在亚微米长度范围内研究材料的组成、结构和光学性质。它与EPSRC战略装备奖密切相关，该奖项提供了一种新的GB 1M场发射枪电子探针微型分析仪(FEG-EPMA)和低电压扫描电子显微镜，这些仪器被配置用于半导体的高空间分辨率X射线显微分析和阴极发光研究。一种靶材是铝合金氮化镓(AlGaN)，它在紫外线能量范围内具有诱人的性能。该项目将对材料性能的理论预测进行实验测试，并旨在展示在不同晶体取向和不同掺杂范围内制备的AlGaN层的质量。这将为在紫外线范围内生产更有效、更紧凑和更高效的设备开辟道路。

This project aims to develop new and enhanced wide band-gap semiconductor alloys, with a view to application in improved devices. In particular, we are targetting ultra-violet (UV) emitters, including those in the deep UV wavelength ranges where there are important applications in water purification and sterilsation, as well as high-frequency high-power transistors. We will work closely with crystal growth specialists, in particular colleagues at Nottingham University, Nagoya University, Nanjing University and CNRS-CRHEA in France. Material produced by epitaxial techniques, such as molecular beam epitaxy, will be characterised by the student using advanced techniques that investigate material composition, structure and optical properties at a sub-micron length scale. It is closely connected to an EPSRC Strategic Equipment Award which provided a new £1M field-emission gun electron probe micro-analyser (FEG-EPMA) and low-voltage scanning electron microscope, which are configured for highly spatially resolved x-ray microanalysis and cathodoluminescence studies of semiconductors. One targetmaterial is the alloy aluminium gallium nitride (AlGaN) which has attractive properties for the UV energy range. The project will experimentally test the theoretical predictions of material properties and aim to demonstrate the quality of AlGaN layers fabricated in a range of crystal orientations and with a range of doping. This will open the way to producing more effective, more compact and more efficient devices in the UV range.