Fraunhofer-Center Nanoelektronische Technologien, Koenigsbruecker Strasse 180, 01099 Dresden, Germany.
Ultramicroscopy. 2011 May;111(6):546-51. doi: 10.1016/j.ultramic.2010.12.028. Epub 2010 Dec 29.
In this paper we present depth profiles of a high-k layer consisting of HfO(2) with an embedded sub-nm thick ZrO(2) layer obtained with atom probe tomography (APT). In order to determine suitable measurement parameters for reliable, reproducible, and quantitative analysis, we have investigated the influence of the laser energy and the specimen temperature on the resulting elemental composition. In addition we devise a procedure for local background subtraction both for the composition and the depth scale that is crucial for gaining reproducible results. We find that the composition of the high-k material remains unaffected even for extreme laser energies and base temperatures, while higher laser energies lead to an accumulation of silicon at the upper interface of the high-k layer. Furthermore we show that APT is capable of providing sub-nm depth resolution for high-k materials with high reproducibility, good compositional accuracy, and high measurement yield.
本文通过原子探针层析术（APT）展示了具有嵌入亚纳米厚 ZrO2 层的高 k 层的深度分布。为了确定合适的测量参数以实现可靠、可重复和定量分析，我们研究了激光能量和样品温度对元素组成的影响。此外，我们还设计了一种局部背景扣除程序，用于组成和深度比例尺，这对于获得可重复的结果至关重要。我们发现，即使在极端的激光能量和基底温度下，高 k 材料的组成也不会受到影响，而更高的激光能量会导致硅在高 k 层的上界面堆积。此外，我们还表明，APT 能够为高 k 材料提供亚纳米的深度分辨率，具有高重复性、良好的组成精度和高测量产率。
