Ionic liquids for subtractive and additive nanomanufacturing

我建议研究离子液体在材料处理中的应用，特别是在纳米技术方面。纳米技术是在接近十亿分之一米的分子尺度上操纵物质。这种规模的制造进步使现代电子和生物医学技术的制造成为可能。然而，需要更先进的工艺来制造更快的计算机、更好的药物输送系统和许多其他未来的技术。在这个项目中，离子液体将被用来获得这些制造工艺的新选择。在过去的二十年里，这些令人兴奋的新液体已经被开发出来，用于一系列化学和能量存储应用。离子液体在室温下完全由带电的复杂分子(离子)组成，这使得使用被称为离子液体离子源(ILIS)的设备来制造纳米技术的新方法成为可能。在离子液体中，离子液体覆盖着一根锋利的针。通过在这个针上施加高电压，就有可能从液体中产生一束离子束。这种喷雾可以直接对准一种材料进行处理。随着人们对离子液体的广泛研究，并发现了数百种稳定的化合物，不同的离子组合将可用于不同的材料加工应用。例如，电子束可以含有活性离子，并可以用来去除硅中的材料，硅是微处理器中常用的材料。改变束流条件和成分可以允许材料的侵蚀(减法)和在表面沉积薄膜或创建结构(加法)。我将探索ILI光束与不同材料的相互作用，研究ILI在材料去除和沉积中的应用，并研究将ILI光束聚焦在纳米级仔细处理材料的可能性。在该研究金的第一阶段(2020-2024年)，建造了一个真空室；该真空室用于详细描述不同离子液体的发射。ILIS光束由几种不同的离子类型组成，因此使用滤光片来分离这些成分。分离的离子类型正在向各种材料发射，以了解特定离子如何与不同的目标反应。这些基础研究得到了实验的补充，这些实验使用ILIS来去除材料并创建纳米级的图案。为了实现更高的吞吐量，可以使用ILIS设备阵列进行额外的实验。从离子液体束沉积离子液体薄膜的可能性也在研究中。该研究项目正在从ILIS开发聚焦离子束(FIB)；FIB机器从离子源获取粒子束，并将粒子聚焦到目标上的纳米级斑点上，从而允许对样品进行局部修改。计算机模拟正被用来设计一种定制的聚焦装置，其中正在安装ILIS。在奖学金的更新阶段(2024-2027)，将进行实验，以量化ILIS-FIB光束在聚焦装置中使用不同的离子液体和不同的操作条件的聚焦效果。ILIS-FIB平台将在几个应用中使用，例如显微镜或纳米级的精密研磨。另一个研究途径将是研究通过离子液体粒子的聚焦离子束沉积材料来创建三维纳米结构的可能性。

I propose investigating the use of ionic liquids for materials treatment, specifically in nanotechnology. Nanotechnology is the manipulation of matter at molecular scales close to one billionth of a meter. Progress in manufacturing at this scale has enabled the fabrication of modern electronic and biomedical technologies. However, more advanced processes are required to manufacture even faster computers, better drug delivery systems, and many other future technologies. In this project, ionic liquids will be used to access new options for these manufacturing processes. These exciting new liquids have been developed over the last two decades for a range of chemistry and energy storage applications. Ionic liquids consist entirely of charged complex molecules (ions) at room temperature, which allows for a new approach to nanotechnology manufacturing with a device known as an Ionic Liquid Ion Source (ILIS). In an ILIS, the ionic liquid covers a sharp needle. By applying a high voltage to this needle, it is possible to produce a beam of ions from the liquid. This spray can be directed towards a material for treatment. Different ion combinations would be available for various materials processing applications, as ionic liquids have been extensively studied, and hundreds of stable compositions have been discovered. For example, the beam can contain reactive ions, and can be used to remove material from silicon, a common material used in microprocessors. Varying the beam conditions and composition can allow for both the erosion of material (subtractive method) and the deposition of a thin film on the surface or to create a structure (additive method). I will explore the interactions of the ILIS beam with different materials, study the use of ILIS for material removal and deposition, and investigate the possibility of focusing the beam of ILIS for careful processing of materials at the nanoscale. In the first stage of this fellowship (2020-2024) a vacuum chamber was constructed; this chamber is being used for detailed characterization of emission from different ionic liquids. ILIS beams are comprised of several different ion types, and so a filter is being used to separate these components. The separate ion types are being fired towards a variety of materials to understand how specific ions react with different targets. These fundamental studies are being complemented by experiments that use an ILIS to remove material and create a nanoscale pattern. Additional experiments can be performed with an array of ILIS devices, in order to achieve higher throughput. The possibility of depositing thin films of ionic liquids from an ILIS beam is also under study. The fellowship is developing a focused ion beam (FIB) from an ILIS; FIB machines take the beam of particles from an ion source and focus the particles onto a nanometre sized-spot on a target, thus allowing localized modifications to a sample. Computer simulations are being used to design a bespoke focusing setup in which the ILIS is being installed.In the renewal stage of the fellowship (2024-2027), experiments will be undertaken to quantify how well the ILIS-FIB beam is focused, using different ionic liquids and different operating conditions in the focusing setup. The ILIS-FIB platform will be used in several applications, for instance microscopy or precise milling at the nanoscale. Another avenue of research will be to study the possibility of creating three-dimensional nanostructures by depositing material with the focused ion beam of ionic liquid particles.