Sensitive optical probes for low pressure plasmas

用于低压等离子体的灵敏光学探头

• 批准号: 2753841
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2753841
• 关键词: Sensitive; optical; probes; low; pressure

This project falls within the EPSRC Plasma and Lasers research area. It will utilise cavity ringdown spectroscopy (CRDS) as a high-resolution experimental technique to investigate trace species within low pressure plasmas. Low pressure plasmas are of high technological interest for micro/nanoelectronics, semiconductors and catalysis, and have secondary multidisciplinary applications in medicine and agriculture. Within the micro/nanoelectronics and semiconductor industries, there is demand for etch processes with atomic level precision and high material selectivity, only possible with plasma enhanced processes. The acceleration of ions towards surfaces is key to high speed chemical vapour deposition and precise etching processes. Utilising plasmas in these technological applications allows otherwise inaccessible conditions to be acheived and significantly reduces the energy cost of maintaining the required conditions, contributing to improved environmental sustainability. Research on the fundamentals behind plasma processing is still limited and enhanced knowledge of ion energy and velocity angular distribution is needed. In particular, the 2022 Plasma Roadmap highlights the lack of knowledge of neutral and ionic species fluxes and emphasises the importance that this knowledge is gained. Therefore, the more complete understanding of plasma characteristics and ion spatial distributions near surfaces which this project will provide will be paramount to advancements within these fields of technology. Previous work on this project within the last year has investigated characteristics of nitrogen plasma. In particular, novel experimental methods were established to quantify the spatial variation of species number densities within the plasma, including within the sheath and pre-sheath regions. This project will continue this work, optimising these methods, and including investigations into other technologically important processing gases such as argon and oxygen. In addition, the ability to manipulate the sheath and presheath regions of the plasma will be investigated through the application of novel rf waveforms and electrode biasing in the plasma chamber, which will also lead to better control of the ion energies impinging on key surfaces. Experimental results obtained will be compared to theoretical models established within the group with the assistance of knowledge from industrial partners, Lam Research Inc. (US), who are global experts within the semiconductor industry and are heavily involved in developing the next generations of fabrication processes for 3D architecture on the nanometre scale. Lam are world leading semiconductor foundry equipment developers, using knowledge of plasma enhanced processes, including chemical vapour deposition, atomic layer deposition, and plasma etching, to produce precise, high performance equipment with the ability to achieve high-aspect ratio features required for micro-electromechanical applications within the industry. This research aligns with the EPSRC's strategies as a discovery research project within mathematical and physical sciences. The outcomes of this project not only will transform our understanding of low pressure plasmas, particularly ion and radical fluxes towards surfaces, but also enable the optimisation of plasma enhanced processes. Once optimisations are implemented on an industrial scale, substantial energy efficiency improvements and cost reductions could be expected, both contributing to a greener future and supporting economic growth within the industry.

该项目属于EPSRC等离子体和激光研究领域。它将利用腔衰荡光谱（CRDS）作为一种高分辨率的实验技术来研究低压等离子体中的痕量物质。低压等离子体在微/纳米电子学、半导体和催化领域具有很高的技术价值，并在医学和农业领域具有次要的多学科应用。在微/纳米电子和半导体工业中，对原子级精度和高材料选择性的蚀刻工艺有需求，只有等离子体增强工艺才有可能实现。离子向表面的加速是高速化学气相沉积和精确蚀刻工艺的关键。在这些技术应用中利用等离子体可以实现其他无法达到的条件，并显着降低维持所需条件的能源成本，有助于提高环境的可持续性。等离子体加工背后的基础研究仍然有限，需要加强对离子能量和速度角分布的了解。特别是，2022年等离子体路线图强调了对中性和离子物种通量知识的缺乏，并强调了获得这种知识的重要性。因此，该项目将提供的对等离子体特性和离子空间分布的更全面的了解将对这些技术领域的进步至关重要。在过去的一年里，这个项目的前期工作已经研究了氮等离子体的特性。特别是，建立了新的实验方法来量化等离子体中物种数量密度的空间变化，包括鞘和鞘前区域。该项目将继续这项工作，优化这些方法，并包括研究其他技术上重要的加工气体，如氩气和氧气。此外，将通过在等离子体室中应用新型射频波形和电极偏置来研究等离子体鞘层和鞘前区域的操纵能力，这也将导致更好地控制离子能量撞击关键表面。在工业合作伙伴Lam Research Inc.（美国）的知识帮助下，将获得的实验结果与小组内建立的理论模型进行比较，Lam Research Inc.是半导体行业的全球专家，并积极参与开发下一代纳米级3D架构的制造工艺。Lam是世界领先的半导体代工设备开发商，利用等离子体增强工艺的知识，包括化学气相沉积，原子层沉积和等离子体蚀刻，生产精确，高性能的设备，能够实现行业内微机电应用所需的高纵横比特性。这项研究与EPSRC作为数学和物理科学领域的发现研究项目的战略相一致。该项目的成果不仅将改变我们对低压等离子体的理解，特别是离子和自由基对表面的通量，而且还可以优化等离子体增强过程。一旦在工业规模上实施优化，可以预期大幅提高能源效率和降低成本，既有助于实现更绿色的未来，又支持行业内的经济增长。