Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Micron. 2011 Aug;42(6):539-46. doi: 10.1016/j.micron.2010.12.008. Epub 2011 Feb 3.
The resolution of electron energy loss spectroscopy (EELS) is limited by delocalization of inelastic electron scattering rather than probe size in an aberration corrected scanning transmission electron microscope (STEM). In this study, we present an experimental quantification of EELS spatial resolution using chemically modulated 2×(LaMnO(3))/2×(SrTiO(3)) and 2×(SrVO(3))/2×(SrTiO(3)) superlattices by measuring the full width at half maxima (FWHM) of integrated Ti M(2,3), Ti L(2,3), V L(2,3), Mn L(2,3), La N(4,5), La N(2,3) La M(4,5) and Sr L(3) edges over the superlattices. The EELS signals recorded using large collection angles are peaked at atomic columns. The FWHM of the EELS profile, obtained by curve-fitting, reveals a systematic trend with the energy loss for the Ti, V, and Mn edges. However, the experimental FWHM of the Sr and La edges deviates significantly from the observed experimental tendency.
电子能量损失谱（EELS）的分辨率受到非弹性电子散射的离域化限制，而不是在像差校正扫描透射电子显微镜（STEM）中的探针尺寸限制。在这项研究中，我们通过测量化学调制的 2×（LaMnO3）/2×（SrTiO3）和 2×（SrVO3）/2×（SrTiO3）超晶格的 Ti M（2,3）、Ti L（2,3）、V L（2,3）、Mn L（2,3）、La N（4,5）、La N（2,3）、La M（4,5）和 Sr L（3）边缘的全宽半最大值（FWHM），对 EELS 空间分辨率进行了实验量化。在超晶格上，使用大收集角记录的 EELS 信号在原子列处达到峰值。通过曲线拟合获得的 EELS 轮廓的 FWHM 揭示了 Ti、V 和 Mn 边缘的能量损失的系统趋势。然而，Sr 和 La 边缘的实验 FWHM 明显偏离了观察到的实验趋势。
