Microanalysis of semiconductor materials for far UV-C applications

电磁波谱的远UV-C区域(波长240 nm)有望在实现联合国可持续目标6：“确保所有人都能获得和可持续管理水和卫生设施”方面发挥重要作用。由于病原体和化合物在远UV-C中表现出吸收，发射和检测远UV-C光可以实现水卫生和水质监测。目前的远UV-C技术使用的是汞、D2或Xe灯和硅探测器，这些灯效率低、危险和体积大，因此不足以应对这一社会挑战。宽禁带半导体自然适合与远UV-C光相互作用，从而生产出紧凑、多功能和安全的设备。尤其是AlGaN、Ga2O3和h-BN是生产远紫外-C激光二极管、发光二极管和光电探测器的有前途的候选材料，但由于它们最近的出现，在这些技术转化到现实世界之前，需要解决一些关于这些材料的问题。例如，材料极化、器件退化或缺陷对器件性能的影响都是生产高效和可靠器件所要解决的重要问题。该项目将利用斯特拉斯克莱德大学的EPSRC战略设备电子探针显微分析仪(EPMA)来研究用于远UV-C应用的宽带隙半导体(AlGaN、Ga2O和h-BN)材料和器件。将扫描电子显微镜(SEM)、能量和波长色散X射线光谱(EDX/WDX)和阴极发光(CL)结合在一个仪器中，为在纳米尺度上深入了解材料的结构、化学和光学性质提供了独特的机会。通过使用Strathclyde集团提供的更广泛的设施，如用于深紫外光发光、紫外光电导的设置，或环境扫描电子显微镜，可以进一步了解材料的性质。最先进的样品将通过Strathclyde集团与学术界和行业建立多年的国际合作(例如与柏林理工大学、AIXTRON有限公司、利物浦大学)建立的国际合作来为该项目提供最先进的样品。该项目将与晶体种植者密切合作，以便深入了解生长对性能的影响，以便生产用于高效远UV-C设备的材料。

The far UV-C region (lambda<240 nm) of the electromagnetic spectrum promises to play an important role towards achieving UN Sustainable Goal No. 6: "ensure availability and sustainable management of water and sanitation for all". Since pathogens and chemical compounds exhibit absorption in the far UV-C, emission and detection of far UV-C light could enable water sanitation and water quality monitoring.Current far UV-C technologies employ Hg, D2 or Xe lamps and Si detectors which are inefficient, hazardous and bulky, and are therefore inadequate to tackle this societal challenge. Wide bandgap semiconductors are naturally suited to interact with far UV-C light and allow to produce compact, versatile and safe devices. In particular, AlGaN, Ga2O3, and h-BN are promising candidates for the production of far UV-C laser diodes, light emitting diodes and photodetectors.However, due to their recent emergence, several questions need to be solved about these materials before these technologies can be transferred to the real world. For example, the question of material polarisation, of device degradation, or of the impacts of defects on device performance are all important questions to tackle to produce efficient and reliable devices. This project will take advantage of the EPSRC strategic equipment Electron Probe MicroAnalyzer (EPMA) at the University of Strathclyde to investigate wide bandgap semiconductors (AlGaN, Ga2O3, and h-BN) materials and devices for far UV-C applications. The combination of scanning electron microscopy (SEM), energy- and wavelength-dispersive X-ray spectroscopy (EDX/WDX) and cathodoluminescence (CL) into a single instrument provides a unique opportunity to gain in-depth knowledge of the structural, chemical, optical properties of the materials at the nanoscale. Further insights into the materials properties will be attained by using the wider range of facilities available at the Strathclyde group, such as the setups for deep UV photoluminescence, for photoconduction in the UV, or the environmental SEMs.State-of-the-art samples will be provided for the project through international collaborations with academia and industry that the Strathclyde group has established for several years (e.g. with Technische Universität Berlin, AIXTRON Ltd, University of Liverpool). The project will be conducted in close collaboration with the crystal growers in order to build an in-depth understanding of how the growth affects the properties in order to produce materials for efficient far UV-C devices.