GOALI: Electrochemistry-based Atomic Layer Etching of Metals for Integrated Circuits

微处理器和存储设备是现代生活中几乎每个方面都使用的电子产品的核心。微处理器的核心是一个复杂的集成电路，它由数十亿个复杂的纳米结构组成。微电路结构的小型化以及随之而来的计算速度和处理能力的指数级增长遵循了“摩尔定律”的预测。这种积极的小型化需要从传统的制造方法到新的纳米制造技术的原子级精确操纵，沉积和蚀刻材料的范式转变。尽管进行了许多努力，但目前还没有一种满足成本和原子级控制要求的用于原子级精确蚀刻的通用技术。这个资助机会学术联络与工业（GOALI）项目推进知识在可扩展的，低成本的电化学过程与创建的途径，定制和蚀刻的金属原子精度。该项目连接了科学和工程的各个学科，包括化学，电化学工程，工艺设计和材料表征。这项研究为研究生和本科生，包括来自代表性不足群体的学生提供教育经验、工业培训和奖学金。与工业界的合作有助于为下一代集成电路的尖端电化学技术开发一个产学合作的模型平台。迄今为止，在半导体的原子层蚀刻方面已经取得了很大进展。然而，金属的原子层蚀刻仍处于起步阶段。等离子体辅助蚀刻金属的方法遇到了许多技术障碍，包括挥发性副产物造成的表面污染和缺乏原子级精度。该项目研究了一种用于金属原子层蚀刻的新液相电化学方法。通过使用新的自限性电化学反应和选择性蚀刻化学，这项研究在原子级精确蚀刻铜等金属方面取得了进展。原子层蚀刻的化学的基本方面进行了调查，导致识别的工艺参数，精密蚀刻集成电路。为了评估原子层蚀刻工艺的放大潜力，在大面积硅晶片上创建纳米图案化几何形状，并进行原位诊断和工艺监测和研究。由此产生的过程可能成为未来纳米电子电路中原子级精确制造结构的推动者。

Microprocessors and memory devices are central to electronic gadgets used in virtually every aspect of modern life. At the heart of a microprocessor is a complex integrated circuitry, which consists of billions of intricately fabricated nanostructures. Miniaturization of micro-circuit structures and ensuing exponential increase in computing speed and processing power has followed the predictions of "Moore's Law". Such aggressive miniaturization necessitates a paradigm shift from traditional manufacturing approaches to newer nanomanufacturing technologies for atomically precise manipulation, deposition and etching of materials. In spite of numerous efforts, a versatile technology for atomically precise etching that meets the requirements of cost and atomic-level control is presently unavailable. This Grant Opportunity for Academic Liaison with Industry (GOALI) project advances knowledge in scalable, low-cost electrochemical processes with the creation of pathways for tailoring and etching of metals with atomic precision. The project bridges various disciplines in science and engineering, including chemistry, electrochemical engineering, process design, and materials characterization. The research provides educational experiences, industrial traineeships and fellowships to graduate and undergraduate students including students from underrepresented groups. Engagement with industry helps develop a model platform for industry-university collaboration on cutting-edge electrochemical technologies for next generation integrated circuits. To date, much progress has been made in the atomic layer etching of semiconductors. However, atomic layer etching of metals is still in its infancy. Plasma-assisted approaches to etch metals have encountered many technical hurdles including surface contamination by volatile byproducts and lack of atomic-level precision. The project investigates a new liquid-phase electrochemical approach for the atomic layer etching of metals. Through the use of novel self-limiting electrochemical reactions and selective etching chemistries, this research advances knowledge in atomically precise etching of metals such as copper. Fundamental aspects of the chemistry of atomic layer etching are investigated leading to the identification of process parameters for precision etching of integrated circuits. To assess the scale-up potential of the atomic layer etching process, nano-patterned geometries on large area silicon wafers are created with in situ diagnostics and process monitoring and studied. The resulting process could become an enabler of atomically precise manufacturing of structures in future nanoelectronics circuits.