Allen Frances I, Blanchard Paul T, Lake Russell, Pappas David, Xia Deying, Notte John A, Zhang Ruopeng, Minor Andrew M, Sanford Norman A
Department of Materials Science and Engineering, UC Berkeley, Berkeley, CA 94720, USA.
National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
Microsc Microanal. 2023 Sep 29;29(5):1628-1638. doi: 10.1093/micmic/ozad078.
We demonstrate a new focused ion beam sample preparation method for atom probe tomography. The key aspect of the new method is that we use a neon ion beam for the final tip-shaping after conventional annulus milling using gallium ions. This dual-ion approach combines the benefits of the faster milling capability of the higher current gallium ion beam with the chemically inert and higher precision milling capability of the noble gas neon ion beam. Using a titanium-aluminum alloy and a layered aluminum/aluminum-oxide tunnel junction sample as test cases, we show that atom probe tips prepared using the combined gallium and neon ion approach are free from the gallium contamination that typically frustrates composition analysis of these materials due to implantation, diffusion, and embrittlement effects. We propose that by using a focused ion beam from a noble gas species, such as the neon ions demonstrated here, atom probe tomography can be more reliably performed on a larger range of materials than is currently possible using conventional techniques.
我们展示了一种用于原子探针断层扫描的新型聚焦离子束样品制备方法。新方法的关键在于，在使用镓离子进行传统环形铣削后，我们使用氖离子束进行最终的尖端成型。这种双离子方法结合了高电流镓离子束更快的铣削能力与惰性气体氖离子束化学惰性和更高精度的铣削能力的优点。以钛铝合金和层状铝/氧化铝隧道结样品作为测试案例，我们表明，使用镓离子和氖离子组合方法制备的原子探针尖端不存在镓污染，而镓污染通常会因注入、扩散和脆化效应而阻碍对这些材料的成分分析。我们提出，通过使用来自惰性气体种类的聚焦离子束，如这里展示的氖离子，与目前使用传统技术相比，原子探针断层扫描可以在更大范围的材料上更可靠地进行。
