Ionic Liquid Ion Sources: the Flexible Ion Beam

离子液体离子源：柔性离子束

• 批准号: EP/V04995X/1
• 负责人: Charles Ryan
• 金额: $ 59.31万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 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=EP%2FV04995X%2F1
• 关键词: Ionic; Liquid; Ion; Sources; Flexible

The use of ion beams for etching is a widely applied technique, providing a valuable tool for completing in situ lithography of micro manufactured components. Today conventional gallium Liquid Metal Ion Sources (LMIS) is the most well appleid focused ion beam etching method, in which gallium ions are extracted from a liquid metal surface through the application of a strong electrostatic field. LMIS offer direct, resistless, three dimensional patterning, but the choice of one ion type is limiting, both in terms of etching rate, etching resolution, and application. The properties of the ion influences significantly the physical and chemical nature of the resulting etched nano and microstructures, limiting the potential application areas. In this project, we propose to investigate the application of an Ionic Liquid Ion Source (ILIS) as an alternative ion beam source for etching. These fundamentally circumvent the limitation of LMIS - the very limited number of ion types available - through using an organic 'ionic liquid' molecule to create the ions. An ionic liquid consists of molecular cations and anions bonded ionically in solution, from which a high electric field can extract a very collimated beam of highly monodisperse molecular ions. Currently over 5000 room temperature variants of ionic liquids are known, with widely varying properties and size of ions, which offer a vast variation in the charged species being emitted, allowing for a bespoke selection of ions (big or small, chemically reactive or inert, capable of ion implantation or not, etc.). This leads to much greater flexibility of the ion beam source, for example allowing for high etching rates using a large ionic liquid molecrular ion, and then switching to a smaller molecular ion (by simple ionic liquid variation), resulting in more accurate final etching.We aim to investigate the potential of applying an ionic liquid ion source to the etching of material substrates. We have developed a novel ionic liquid ion source that produces a high-energy monodisperse ion beam, using an ionic liquid demonstrated to produce good etching capability. We aim to demonstrate that it can offer an alternative to conventional liquid metal ion sources, whilst investigating the fundamental phenomena that enable ILIS devices to operate.There are three main subjects that will be investigated in this project. Firstly a systematic analysis of ionic liquid ion sources for micro fabrication will be completed. Studies have demonstrated the promising nature of the technique, but to a limited aspect and not fully investigating its wide potential. We will complete a systematic study of the technique, providing a comprehensive data set which will highlight where the technique can be particularly advantageous. Secondly there is a need for greater understanding of how the ionic liquid ion source operates. The source can produce a highly monodisperse beam, but the parameters that affect this beam output (liquid properties, source design) are incompletely understood. We will apply theoretical and simulation techniques complimented by experimental analysis of the plume to greater understand the processes that are occurring. This will feed into the design of the source.Thirdly the lessons learnt from the above analysis will allow us to produce a ionic liquid ion source designed specifically for etching processes, rather than an adaptation of spacecraft propulsion ion thrusters that will be used at the start of the project.

利用离子束进行刻蚀是一种应用广泛的技术，为完成微制造元件的原位光刻提供了有价值的工具。目前，传统的镓液态金属离子源(LMI)是应用最广泛的聚焦离子束刻蚀方法，即通过施加强静电场从液态金属表面提取镓离子。LMI提供直接、无阻力的三维图形，但在刻蚀速度、刻蚀分辨率和应用方面，一种离子类型的选择是有限的。离子的性质极大地影响了由此产生的蚀刻纳米和微结构的物理和化学性质，限制了潜在的应用领域。在这个项目中，我们打算研究离子液体离子源(ILIS)作为一种替代的离子束源用于刻蚀的应用。这从根本上绕过了LMI的限制--可用的离子类型非常有限--通过使用有机“离子液体”分子来产生离子。离子液体由离子键合在溶液中的分子阳离子和阴离子组成，在高电场的作用下，可以产生高度单分散的非常平行的分子离子束。目前已知的离子液体的室温变体有5000多种，离子的性质和大小差别很大，这些离子在发射的带电物种上提供了巨大的变化，允许定制选择离子(大或小，化学活性或惰性，能够或不能离子注入等)。这使得离子束源具有更大的灵活性，例如，允许使用大的离子液体分子离子进行高的刻蚀速率，然后切换到较小的分子离子(通过简单的离子液体变化)，从而产生更准确的最终刻蚀。我们的目标是研究将离子液体离子源应用于材料衬底的刻蚀的可能性。我们开发了一种新型的离子液体离子源，它可以产生高能的单分散离子束，使用的离子液体被证明能够产生良好的刻蚀能力。我们的目标是证明它可以提供一种替代传统的液态金属离子源，同时研究使ILIS设备运行的基本现象。在这个项目中将研究三个主要主题。首先，对用于微加工的离子液体离子源进行了系统的分析。研究已经证明了这项技术的前景，但仅限于有限的方面，还没有充分研究它的广泛潜力。我们将完成对这项技术的系统研究，提供一个全面的数据集，突出这项技术的优势所在。其次，需要更好地了解离子液体离子源是如何运行的。这种光源可以产生高度单色散的光束，但影响这种光束输出的参数(液体性质、光源设计)还不完全清楚。我们将应用理论和模拟技术，并辅之以对羽流的实验分析，以更好地了解正在发生的过程。第三，从上述分析中吸取的经验教训将使我们能够生产出专门为蚀刻过程设计的离子液体离子源，而不是在项目开始时将使用的航天器推进离子推进器的改装。

项目成果

Optical Emission Characterization of a Single Emitter Electrospray Thruster Interacting With Surfaces

与表面相互作用的单发射器电喷雾推进器的光发射表征

• DOI: 10.2514/6.2023-1409
• 发表时间: 2023
• 作者: Turan N