Construction of response function of TES X-ray microcalorimeter for STEM-EDS
Construction of response function of TES X-ray microcalorimeter for STEM-EDS
复制标题
STEM-EDS TES X射线微量热计响应函数的构建
DOI：
10.1109/tasc.2019.2902304
复制
发表时间：
2019
影响因子：
1.8
通讯作者：
Keisuke Maehata and Toru Hara
中科院分区：
文献类型：
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作者：
Tasuku Hayashi;Haruka Muramatsu;Keisei Maehisa;Noriko Y. Yamasaki;Kazuhisa Mitsuda;Keisuke Maehata and Toru Hara
天体材料的定量微观分析（例如，陨石，从小行星返回的样品）是了解我们太阳系形成历史的关键技术。为了实现这一点，我们开发了一种能量色散X射线光谱（EDS）使用的过渡边缘传感器（TES）微量热计阵列上的扫描透射电子显微镜（STEM）的材料分析。为了减少光谱分析的系统误差，我们研究并构建了STEM-EDS系统的响应函数，该响应函数由检测效率和二维响应矩阵组成。后者表示不同能量的入射光子的脉冲高度再分布函数。利用所构造的响应函数对SiO_2薄膜进行了定量测定，证实了在统计误差范围内，氧硅数密度比（=2.29-0.29+0.32）与期望值2一致。我们进一步研究的系统误差的浓度测定与模拟。在没有连续谱先验知识的情况下，我们对TES-EDS和SDD-EDS的模拟谱进行了分析，发现TES-EDS的参数与模型值的系统偏差小于1%，SDD-EDS的参数与模型值的系统偏差大于10%。
A quantitative microanalysis of astromaterials (e.g., meteorite, returned samples from asteroids) is a key technology to understand the history of our solar system formation. To fulfill this, we developed an energy-dispersive X-ray spectroscopy (EDS) using a transition-edge sensor (TES) microcalorimeter array on a scanning transmission electron microscope (STEM) for material analysis. To reduce the systematic errors of a spectral analysis, we investigated and constructed the response function of the STEM-EDS system, which consists of detection efficiency and a two-dimensional response matrix. The latter represents the pulse-height redistribution functions of the incident photons of different energies. Using the constructed response function, we demonstrated the quantitative determination of SiO2film and confirmed that the number-density ratio of oxygen to silicon (=2.29-0.29+0.32) is consistent with the expected value of 2 within the statistical errors. We further study the systematic errors of the concentration determination with simulations. We analyze the simulated spectra of TES-EDS and SDD (silicon drift detector)-EDS without a priori knowledge about the continuum spectra and find that the systematic deviations of parameters from the model values are smaller than 1% for TES-EDS and larger than 10% for SDD-EDS.