High Five: Resolution, Sensitivity, in operando Control, Ultra High Vacuum and Ion Sectioning in a Single Instrument

建议的仪器是超高真空(UHV)等离子体聚焦离子束SIMS(PFIB-SIMS)的新组合，在分辨率、灵敏度和适用性方面提供了最先进的仪器性能的阶梯变化。其他功能包括双动态正负离子检测、微结构分析、用于在手术研究中的性能的电气和热控制以及通过结合预燃室处理空气敏感材料。这一全球独一无二的设计将能够以纳米分辨率对复杂表面进行化学量化，并进行3D化学和微结构重建，填补现有SIMS和FIB技术的维度空白。在特高压环境中，所使用的配置和组件处于材料切片和表面特征设计的前沿。二次离子的来源是气体等离子体聚焦离子束(FIB)源和柱，它可以产生焦点为25 nm的氧离子或氙离子，以获得最高的横向分辨率。该来源还能够通过3D连续切片和表征，将硬材料和软材料切割到长达一毫米的尺度，以用于地下块状特征。低能量的铯表面剂量也可用于提高电负性元素(如O)的二次离子产额。帝国理工学院率先推出了同时进行正负SIMS离子检测，目前在这种独特的SIMS分析配置中通过离子轨迹建模进行了优化。具有粗糙度和形状的样品是合适的，因为两个基于电四极杆的质谱仪的信号提取所固有的低电场是合适的。可提供样品冷却和加热，以及用于IV测试和样品表面接地的现场电触点。除了通常的超高压仪器负载锁外，还将有第二个准备/负载锁定室，用于通过温度控制和电触点来处理样品，以反映主要的SIMS分析室设施。此外，还可以使用气体分析设施将退火气环境控制到大气压。制备/加载锁定室提供了一种在真空或气体环境中从其他制备和表征设施转移空气敏感样品的方法，例如干燥手套箱、扫描电子显微镜、XPS和钻石。仪器配置的一个独特特点是提供了从两个加载锁中的样品获得光学图像的规定，包括用于地形评估的光学干涉图像。仪器配置的设计考虑到了固有的防未来，因为分析室和准备/加载锁都具有大容量和备用访问端口。在分析室中，使用大工作距离、约15 mm、用于SIMS信号的低电场提取和精确的5轴工作台移动，意味着可以从立体角度访问分析室内的样品目标位置。仪器将放置在现有的专业表面分析实验室中，高性能SIMS/LEIS设备位于该实验室，配备有在优化离子束分析条件和方法方面具有世界领先专业知识的永久离子束专家。最后，将向用户提供数据解释方面的协助，并提供击掌操作方面的专门知识。

The proposed instrument is a novel combination of ultra-high vacuum (UHV) Plasma Focused Ion Beam SIMS (PFIB-SIMS) that provides a step change in performance of state-of-the-art instrumentation in terms of resolution, sensitivity and applicability. Additional features are dual dynamic positive and negative ion detection, micro-structural analysis, electrical and thermal control for the performance of in operando studies and handling of air-sensitive materials by the incorporation of a pre-chamber. This design, unique worldwide, will enable the chemical quantification of complex surfaces with nanometric resolution and 3D chemical and microstructural reconstruction filling the dimensionality gap in the existing SIMS and FIB technology. The configuration and components used are at the forefront of materials sectioning and surface characterisation design in a UHV environment. The source of the secondary ions is the gas plasma focused ion beam (FIB) source and column that can produce either oxygen ions or xenon ions with a focus of 25nm for the highest lateral resolutions. This source is also able to section hard and soft materials to length scales of up to a millimetre for sub-surface bulk features by 3D serial-sectioning and characterisation. Low energy surface dosing with caesium is also available for enhancing the secondary ion yields of electronegative elements (e.g. O).Simultaneous positive and negative SIMS ion detection has been pioneered at Imperial College and is now optimised by ion trajectory modelling in this unique SIMS analysis configuration. Samples with both roughness and form are suitable as low electrical fields are inherent for signal extraction by the two electric quadrupole-based mass spectrometers. Sample cooling and heating is available, also in-situ-electrical contacts for IV testing and grounding at sample surfaces.Apart from the usual loadlock for a UHV instrument, there will be a second preparation/load-lock chamber for sample processing by temperature control and electrical contacts to mirror the main SIMS analysis chamber facilities. Additionally it will be possible to control the anneal gas ambient to atmospheric pressure with a gas analysis facility. The preparation/load-lock chamber provides a means of transferring air-sensitive samples in vacuum or gas environment from other preparation and characterisation facilities such as a dry Glove-box, SEM, XPS, and Diamond for example. A unique feature of the instrument configuration is the provision for obtaining optical images from samples in both load-locks including optical interference images for topography assessment.The instrument configuration is designed with inherent future-proofing in mind as both the analysis chamber and the preparation/load-lock have large volumes and spare access ports. In the analysis chamber, the use of a large working distance, ~15mm, low electric field extraction for the SIMS signal and accurate 5-axis stage movements means that there is available solid-angle access to the sample target position within the analysis chamber.The instrument will be placed in an existing specialist surface analysis laboratory where high performance SIMS/LEIS equipment is located and staffed by permanent ion beam specialists with world leading expertise in optimising ion beam analysis conditions and methodologies. Finally, assistance in data interpretation will be available to the user as well expertise in the operation of High Five.