CDT Compound Semiconductor Physics (PhD Progression 1+3)

CDT 化合物半导体物理（博士进修 1 3）

• 批准号: 2882476
• 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-2882476
• 关键词: CDT; Compound; Semiconductor; Physics; PhD

Vertical cavity surface emitting lasers (VCSELs) have widespread use in applications such as datacoms, atomic clocks, LiDAR, face/gesture recognition and augmented reality. In the field of neuromorphic computing, optical pulses or 'spiking' is used to imitate the firing of neurons. If designed in the correct way, VCSELs can also be used to target photosensitive proteins (opsins), causing activation of biological neurons used in optogenetic therapy. Combining this with a VCSEL designed for spiking in neuromorphic computing could provide an effective route to neural-protheses (brain-computer interfacing), an exciting new area of neuroscience and biomedical engineering. Individually, VCSELs are relatively low power emitters (10s mW), but in arrays or coupled configurations this power can be scaled, albeit with appropriate thermal management. Germanium (Ge) substrates have a higher thermal conductivity than gallium arsenide and allow for thinner substrates further aiding heat extraction, an area which can be explored in the project. Depending on the configuration, arrays of VCSELs can be sparsely or densely packed together and this can cause significant variation in device architecture due to the impact on process parameters, such as 'aspect-ratio dependant etching'. Additionally, the need for gain and saturable absorber sections in short-pulse VCSELs requires careful control of etching parameters to meet the required depths for intra-cavity electrical contacts. This project will focus on optimising process parameters to achieve addressable arrays of VCSELs for spiking or high pulse-powers and testing will be used to inform improvements in fabrication. Furthermore, routes to separate out dense arrays using plasma-die separation techniques will be explored, in the case of Ge substrates this can become critical due to cleaving difficulties.

垂直空腔表面发射激光器（VCSEL）在数据，原子钟，LIDAR，面部/手势识别和增强现实等应用中广泛使用。在神经形态计算领域，光脉冲或“尖峰”用于模仿神经元的发射。如果以正确的方式设计，VCSEL也可以用于靶向光敏蛋白（OPSINS），从而导致在光遗传学疗法中使用的生物神经元激活。将其与设计用于神经形态计算的VCSEL结合使用，可以为神经皮革（脑部计算机接口）提供有效的途径，这是一个令人兴奋的神经科学和生物医学工程的新领域。单独的VCSEL是相对较低的功率发射器（10s MW），但是在阵列或耦合配置中，该功率可以缩放，尽管具有适当的热管理。锗（GE）底物的导热率比砷化韧带高，并且可以使较薄的底物进一步辅助热提取，该区域可以在项目中探索。根据配置，VCSEL的阵列可以稀疏或密集地包装在一起，这可能会导致设备体系结构的显着变化，因为对过程参数的影响，例如“依赖于方面比例依赖性蚀刻”。此外，在短脉冲VCSEL中需要获得的增益和饱和吸收器切片需要仔细控制蚀刻参数，以满足用于腔内电气接触的所需深度。该项目将着重于优化过程参数，以实现用于尖峰或高脉冲能力的VCSEL的可寻址阵列，并将使用测试来指导制造的改进。此外，将探索使用等离子体-DIE分离技术分离致密阵列的路线，在GE基板的情况下，由于裂解困难，这可能变得至关重要。