Development of high-resolution focussed ion beam-secondary ion mass spectrometry (FIB-SIMS) as a tool for Earth and Materials sciences

扫描电子显微镜（SEM）和聚焦离子束-扫描电子显微镜（FIB-SEM）结合能量色散谱（EDS）和电子背散射衍射（EBSD）允许数十至数百微米面积的组成和晶体学映射，具有潜在的100 nm空间分辨率或更好。这里的问题是EBSD和EDS对轻元素或同位素不敏感。在这个项目中，我们将开发一种新的分析层析方法，使用FIB结合二次离子质谱（西姆斯）。这种层析成像技术将被整合到一个相关的方法，使用光学显微镜，X射线层析成像，透射电子显微镜和原子探针tomography.The显微镜技术开发期间，该项目将被用来解决各种复杂的材料表征问题，在天然和合成样品。这包括表征微量元素和同位素组成的包体中发现的锆石从西澳大利亚州的杰克山。了解这些样品中发现的包裹体的矿物年龄有可能解开古地磁学中悬而未决的关键问题，例如地球磁场是何时开始的？此外，页岩和砂岩的西姆斯分析将用于了解在孔隙尺度上发生的溶解和再沉淀过程，从而了解石油和天然气储层行为。这种相关分析层析成像也将用于探索对能量存储重要的其他材料的化学行为，例如固体氧化物电池。最后，这可用于解决钢和核材料中轻元素沿沿着的偏析。该项目的重点是探索西姆斯断层扫描FIB-SEM和离子束显微镜的潜力，以开发一种质谱技术，解决ICPMS和APT之间的长度尺度信息差距。西姆斯作为一种分析技术，提供的信息与传统的EDS分析有很大的不同。值得注意的是，西姆斯使得可以以数十纳米的空间分辨率分析样品中的两种同位素痕量轻元素分布。此外，学生还将使用这种新的断层扫描作为综合工作流程的一部分设计和实施实验，从X射线和光学到TEM或APT（毫米到原子）。在长度尺度上保持数据连接学生将开发一种新的尖端分析层析技术，结合使用离子束对样品进行连续测序，然后将其与西姆斯数据相结合，以创建所研究体积的三维元素图。这项新技术将开辟通过样品对同位素和痕量/轻元素分布的三维探索。使用这种技术，学生将探索有关流体岩石相互作用的问题和与深部碳有关的问题。此外，技术上重要的材料涉及能量储存和回收以及先进的冶金问题。

Scanning electron microscopy (SEM) and focused ion beam - scanning electron microscopy (FIB-SEM) combined with energy dispersive spectroscopy (EDS) and electron backscatter diffraction (EBSD) allow for compositional and crystallographic mapping of tens to hundreds of microns of area, with potentially 100 nm spatial resolution or better. The problem here is that EBSD and EDS are not sensitive to light elements or isotopes. In this project we will develop a new analytical tomographic approach using the FIB combined with secondary ion mass spectroscopy (SIMS). This tomographic technique will be integrated into a correlative approach using optical microscopy, x-ray tomography, transmission electron microscopy and atom probe tomography.The microscopy techniques developed during this project will be used to address a variety of complex materials characterization problems in natural and synthetic samples. This includes characterizing the trace element and isotope compositions of inclusions found in zircons from the Jack Hills of Western Australia. Understanding the mineral ages of the inclusions found in these samples has the potential to unlock key outstanding questions in paleomagnetism, such as when did the Earth's magnetic field begin? Additionally, SIMS analysis of shale and sandstones will be used to understand dissolution and re-precipitation processes occurring at the pore scale relevant to understanding oil and gas reservoir behavior. This correlative analytical tomography will also be used to explore chemical behaviors in other materials important to energy storage, such as solid oxide batteries. Finally, this can be used to address light-element segregation along grain boundaries in steels and nuclear materials. FIB-SIMS enabled tomography directly addresses an analytical length-scale and information gap, which is important for the characterization of natural and synthetic materials.This project focuses on exploring the potential of SIMS tomography FIB-SEM and ion beam microscopes to develop a mass spectroscopic technique that addresses the length scale information gap between ICPMS and APT. SIMS as an analytical technique offers information significantly differ from that traditionally measured using EDS analysis. Significantly, SIMS makes it is possible to analyze both isotope trace light element distributions in a sample with a spatial resolution of tens of nanometers. Further, the student will also design and implement experiments using this new tomography as part of an integrated workflow, going from x-ray and optical down to TEM or APT (mm to atoms). Maintaining a data connection across length scales.The student will develop a new cutting edge analytical tomographic technique, combining the sequential sequencing of a sample using an ion beam and then combining it with SIMS data to create a three dimensional elemental map of the studied volume. This new technique will open up three-dimensional explorations into isotope and trace/ light element distributions through a sample. Using this technique the student will explore questions about fluid rock interactions and questions related to deep carbon. Further, technologically important materials related to the energy storage, and recovery as well as advanced metallurgical questions.