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的技术。这种规模的制造业进步使现代电子和生物医学技术得以实现。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技术。在这个项目中，离子液体将被用来为这些制造过程提供新的选择。在过去的二十年里，这些令人兴奋的新型液体已经被开发出来，用于一系列化学和能量存储应用。在室温下，离子液体完全由带电的复杂分子（离子）组成，这使得一种名为离子液体离子源（ILIS）的设备成为纳米技术制造的新途径。在ILIS中，离子液体覆盖着一根锋利的针。通过给这根针施加高电压，就有可能从液体中产生一束离子。这种喷雾可以直接喷向要处理的材料。不同的离子组合可用于不同的材料加工应用，因为离子液体已经被广泛研究，并且已经发现了数百种稳定的成分。例如，光束可以包含活性离子，可以用来去除硅中的物质，硅是微处理器中常用的材料。改变光束条件和组成可以允许材料的侵蚀（减法方法）和在表面上沉积薄膜或创建结构（加法方法）。我将探索ILIS光束与不同材料的相互作用，研究ILIS用于材料去除和沉积的使用，并研究聚焦ILIS光束在纳米尺度上仔细处理材料的可能性。在该奖学金的第一阶段（2020-2024），建造了一个真空室；该腔室用于详细表征不同离子液体的发射。ILIS光束由几种不同的离子类型组成，因此使用过滤器来分离这些成分。不同类型的离子被发射到各种各样的材料上，以了解特定的离子如何与不同的目标反应。这些基础研究正在通过使用ILIS去除材料并创建纳米级图案的实验得到补充。额外的实验可以执行与阵列的ILIS设备，以实现更高的吞吐量。从ILIS光束沉积离子液体薄膜的可能性也在研究中。该研究项目正在开发一种来自ILIS的聚焦离子束（FIB）；FIB机器从离子源获得粒子束，并将粒子聚焦到目标上的纳米大小的点上，从而允许对样品进行局部修改。计算机模拟被用来设计一个定制的聚焦装置，ILIS将被安装在其中。在奖学金的更新阶段（2024-2027），将在聚焦装置中使用不同的离子液体和不同的操作条件，进行实验来量化ILIS-FIB光束的聚焦效果。ILIS-FIB平台将用于多种应用，例如显微镜或纳米级精密铣削。另一个研究方向将是研究用离子液体粒子的聚焦离子束沉积材料来制造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.