Chiaramonti Ann N, Miaja-Avila Luis, Blanchard Paul T, Diercks David R, Gorman Brian P, Sanford Norman A
National Institute of Standards and Technology, Boulder, CO, USA.
Colorado School of Mines, Golden, CO, USA.
MRS Adv. 2019 Jul 3;4(44-45). doi: 10.1557/adv.2019.296.
Pulsed coherent extreme ultraviolet (EUV) radiation is a potential alternative to pulsed near-ultraviolet (NUV) wavelengths for atom probe tomography. EUV radiation has the benefit of high absorption within the first few nm of the sample surface for elements across the entire periodic table. In addition, EUV radiation may also offer athermal field ion emission pathways through direct photoionization or core-hole Auger decay processes, which are not possible with the (much lower) photon energies used in conventional NUV laser-pulsed atom probe. We report preliminary results from what we believe to be the world's first EUV radiation-pulsed atom probe microscope. The instrument consists of a femtosecond-pulsed, coherent EUV radiation source interfaced to a local electrode atom probe tomograph by means of a vacuum manifold beamline. EUV photon-assisted field ion emission (of substrate atoms) has been demonstrated on various insulating, semiconducting, and metallic specimens. Select examples are shown.
脉冲相干极紫外(EUV)辐射是用于原子探针断层扫描的脉冲近紫外(NUV)波长的一种潜在替代方案。EUV辐射的优势在于,对于整个周期表中的元素,在样品表面的最初几纳米内具有高吸收率。此外,EUV辐射还可能通过直接光电离或芯孔俄歇衰变过程提供无热场离子发射途径,而这对于传统NUV激光脉冲原子探针中使用的(低得多的)光子能量来说是不可能的。我们报告了我们认为是世界上第一台EUV辐射脉冲原子探针显微镜的初步结果。该仪器由一个飞秒脉冲相干EUV辐射源组成,通过真空歧管束线与局部电极原子探针断层仪相连。已经在各种绝缘、半导体和金属样品上证明了(衬底原子的)EUV光子辅助场离子发射。展示了一些选定的示例。