Large volume serial section tomography by Xe Plasma FIB dual beam microscopy
Large volume serial section tomography by Xe Plasma FIB dual beam microscopy
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DOI：
10.1016/j.ultramic.2015.11.001
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发表时间：
2016-02-01
期刊：
影响因子：
2.2
通讯作者：
Withers, P. J.
中科院分区：
文献类型：
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作者：
Burnett, T. L.;Kelley, R.;Withers, P. J.
Ga+聚焦离子束扫描电子显微镜(FIB-SEM)彻底改变了可通过块面连续切片断层扫描(SST)在3D中恢复的微结构信息的水平，并能够针对特定部位去除较小区域，以便进行后续的透射电子显微镜(TEM)检查。然而，Ga+FIB材料的去除率限制了可以探测到几十微米范围内的体积和深度。新兴的Xe+等离子体聚焦离子束扫描电子显微镜(PFIB-SEM)系统承诺更快的去除速度。在这里，我们研究了大体积连续截面层析成像方法的潜力，并将其应用于贝氏体钢和WC-Co硬质合金。我们的研究表明，在仔细控制铣削参数的情况下，可以在去除速度快约60倍的情况下，以较低的铣削伪影水平实现精确的自动连续切片。使用全自动SST程序在可行的时间尺度(<；24小时)收集了尺寸为数百微米的体积，显示了良好的颗粒取向对比度，并捕获了数十纳米到数十微米尺度的微结构特征。伴随而来的电子背散射衍射(EBSD)图显示高指标率，表明表面损伤程度较低。此外，在大电流条件下，WC-Co容易发生WC表面层的非晶化和Co相的相变，而在30kV高达60nA的PFIB电流下，没有观察到这两种现象。XE+PFIB双光束显微镜有望从根本上扩展我们的3D断层扫描、3D EDX、3D EBSD以及相关断层扫描的能力。(C)2015年提交人。爱思唯尔出版公司(Elsevier B.V.)
Ga+ Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga+ FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe+ Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC-Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60 x faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (< 24 h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga+ FIB milling WC-Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60 nA at 30 kV. Xe+ PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography. (C) 2015 The Authors. Published by Elsevier B.V.