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Ultramicroscopy. 2011 Nov;111(11):1564-73. doi: 10.1016/j.ultramic.2011.08.016. Epub 2011 Sep 5.
30keV Ga(+) focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z(2), and shows a non-monotonic relationship between contrast and Z(2). The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion-solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z(2), following the periodic behavior of the stopping power for electron-solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle-solid interaction theory.
30keV Ga(+)聚焦离子束诱导二次电子（iSE）成像用于确定几种材料之间的相对对比度。从 C、Si、Al、Ti、Cr、Ni、Cu、Mo、Ag 和 W 金属层比较的 iSE 信号不会随目标原子数 Z(2)的增加而降低，并且对比度与 Z(2)之间呈现非单调关系。这种非单调关系归因于离子-固体相互作用固有的阻止能力和溅射产额的周期性波动。此外，使用扫描电子显微镜 (SEM) 的电子诱导二次电子 (eSE) 和背散射电子 (BSE) 图像的材料对比度也表现出与 Z(2)的非单调对比度，遵循电子-固体相互作用的阻止能力的周期性行为。iSE 和 eSE 结果的比较表明，金属层之间的相对对比度相似，而不是传统理解的互补对比度。这种对比度行为的相似性可以归因于入射粒子-固体相互作用理论定义的周期性和非单调函数的相似性。
