GOALI: In-Situ Plasma Cleaning of Optics: Building a Fundamental Understanding of the Etch Process in a Complex Plasma Environment

极紫外（EUV）光作为生产未来复杂紧凑集成电路的光源具有强大的前景。不幸的是，目前由于大批量生产的低成本效率而阻碍了实际的经济使用。EUV光源使用锡（Sn）液滴来产生13.5nm的光，该光由收集器光学器件收集并传输到扫描仪中。Sn沉积在收集器表面上并降低EUV反射率。使用氢自由基清洁Sn是一种潜在的解决方案。该奖项支持伊利诺伊大学厄巴纳尚潘分校的应用研究所与其工业合作伙伴合作进行基础研究，以推进对使用氢自由基的Sn蚀刻工艺的基本物理和化学的基本理解。这项研究将被证明是下一代芯片制造工艺成功的里程碑，这将使该技术的成本效益实现，以打印更智能的芯片，并最终提高电子设备的速度和性能。本研究的首要目标是将研究成果融入学术课程，学生参与工业，并吸引年轻科学家进入等离子体工程的广阔领域。本项目是一个假设驱动的，理论和实验研究在复杂的等离子体环境中从光学器件中清洗锡。它侧重于对氢等离子体中反应性粒子形成的基本理解，其到达和与表面的相互作用，吸附机制，与待蚀刻表面的键合形成，以及最终在EUV源操作环境下产物分子的形成和解吸。该团队将对氢等离子体条件和蚀刻速率的依赖性进行彻底的计算分析。蚀刻实验将运行，以验证模型预测的蚀刻速率。工业合作伙伴将通过提供必要的设备、计量和等离子体源来推动这项研究。该研究将回答等离子体材料相互作用，表面科学，等离子体加工和蚀刻领域的基本问题。

Extreme-Ultraviolet (EUV) light holds strong promise as a light source for producing tomorrow's complex and compact integrated circuits. Unfortunately, practical economic use is currently precluded by low cost-efficiency for high volume manufacturing. The EUV source uses tin (Sn) droplets to produce the 13.5nm light, which is collected and transmitted into a scanner by collector optics. Sn deposits on the collector surface and degrades the EUV reflectivity. Cleaning Sn using hydrogen radicals is a potential solution. This Grant Opportunity for Academic Liaison with Industry (GOALI) award supports the Applied Research Institute at the University of Illinois at Urbana Champaign to perform basic research in collaboration with its industrial partners to advance the fundamental understanding of the underlying physics and chemistry of Sn etch process using hydrogen radicals. This research will prove to be a milestone in the success of the next generation chip manufacturing process, which will enable a cost effective implementation of the technology to print smarter chips and eventually improve the speed and performance of electronic devices. An overarching goal of this research is the integration of research findings into academic courses, student involvement with industry, and attracting young scientists into the vast field of plasma engineering.This project is a hypothesis-driven, theoretical and experimental study of Sn cleaning from optics in a complex plasma environment. It focuses on fundamental understanding of reactive particle formation in hydrogen plasma, its arrival and interaction with surfaces, adsorption mechanisms, bond formation with the surface to be etched, and then finally the formation and desorption of product molecules under the EUV source operating environment. The team will perform a thorough computational analysis of the dependencies of hydrogen plasma conditions and etch rate. Etching experiments will be run to validate the etch rates predicted by the models. Collaborative industrial partners will help by providing necessary equipment, metrologies and the plasma source to advance this research. The research will answer fundamental questions in the field of plasma material interaction, surface science, plasma processing and etching.