MSc Compound Semiconductor Electronics (PhD Progression 1+3)

化合物半导体电子学理学硕士（博士升读 1 3）

• 批准号: 2888740
• 金额: --
• 依托单位: CARDIFF UNIVERSITY
• 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-2888740
• 关键词: MSc; Compound; Semiconductor; Electronics; PhD

The team in Cardiff successful grows epitaxial gallium nitride (GaN) layers on (111) silicon (Si) substrates. This may be one solution to enable integration of light emitting diodes (LEDs) for photonics onto standard Si process technology production lines. Key issues are wafer cracking due to -17% tensile strain of the GaN and the generation of dense misfit dislocation networks due to the misfit and the thermal expansion mismatch between GaN and Si and also the formation of good ohmic electrical contacts for device operation. Various methods to explore and reduce lattice strain will be investigated in this combined electron microscopy and electron spectroscopy study where one key question to answer is whether and to what degree the anneal of the electrical contacts enhances strain relaxation in the GaN layers underneath.Conventional electron diffraction contrast (EDC), high-resolution lattice imaging (HREM), and annular dark-field (ADF) scanning transmission electron microscopy (STEM) will be used in project A to image dislocation lines and measure their density in plan-view (top-down) geometry, and to determine the dislocation types and image their cores in cross-sectional geometry.

卡迪夫的团队成功在 (111) 硅 (Si) 衬底上生长外延氮化镓 (GaN) 层。这可能是一种能够将光子学发光二极管 (LED) 集成到标准硅工艺技术生产线上的解决方案。关键问题是由于 GaN 的 -17% 拉伸应变导致的晶圆破裂，以及由于 GaN 和 Si 之间的失配和热膨胀失配而产生的密集失配位错网络，以及器件运行所需的良好欧姆电接触的形成。在这项电子显微镜和电子能谱相结合的研究中，我们将研究探索和减少晶格应变的各种方法，其中需要回答的一个关键问题是电接触退火是否以及在多大程度上增强了下面 GaN 层的应变弛豫。传统电子衍射衬度 (EDC)、高分辨率晶格成像 (HREM) 和环形暗场 (ADF) 扫描透射电子 项目 A 将使用显微镜 (STEM) 对位错线进行成像并测量其在平面图（自上而下）几何形状中的密度，并确定位错类型并在横截面几何形状中对其核心进行成像。