Cameca Instruments, Inc., formerly Imago Scientific Instruments Corporation, 5500 Nobel Drive, Madison, WI 53726, USA.
Microsc Microanal. 2011 Feb;17(1):1-14. doi: 10.1017/S1431927610094468. Epub 2011 Jan 19.
The benefits of using kinetic-energy information to aid ion discrimination in atom probe tomography (APT) are explored. Ion peak interferences in time-of-flight (TOF) mass spectra are categorized by difficulty of discrimination using TOF and kinetic-energy information. Several of these categories, which are intractable interferences when only TOF information is available, may be discriminated when kinetic-energy information also is available. Furthermore, many opportunities for removing noise from composition determinations and three-dimensional images are enabled. Modest kinetic-energy resolving powers (KRPs) of 10 or so should be sufficient to have a major impact on APT. With KRP of about 100, the energy deficits in voltage pulsing may be resolved to enable peak discrimination in straight-flight-path instruments. Real examples and simulated mass spectra are used to illustrate the benefits of kinetic-energy discrimination. Many of the conclusions are applicable generally in TOF spectroscopy. Current detectors do not provide the kinetic energy of incoming ions, but there are realistic prospects for building such detectors and these are discussed. A program to develop these detectors should be pursued.
探讨了利用动能信息辅助原子探针断层成像术（APT）中的离子甄别。根据利用飞行时间（TOF）和动能信息进行甄别时的难度，对 TOF 质谱中的离子峰干扰进行了分类。在仅使用 TOF 信息时难以区分的几个类别，如果同时使用动能信息，可能会被区分开来。此外，还为从成分测定和三维图像中去除噪声提供了许多机会。适度的动能分辨力（KRPs）约为 10 左右，应该足以对 APT 产生重大影响。当 KRP 约为 100 时，电压脉冲的能量不足可以得到解决，从而可以在直飞行路径仪器中进行峰甄别。使用真实示例和模拟质谱来说明动能分辨的好处。许多结论在 TOF 光谱学中都具有普遍适用性。当前的探测器无法提供入射离子的动能，但构建此类探测器具有现实的前景，对此进行了讨论。应该开展开发这些探测器的计划。
