Spectroscopy and Spectral Analysis, Volume. 44, Issue 5, 1297(2024)

Analysis and Calculation of Escape Peaks in Silicon Drift Detectors

LIAO Xue-liang*... LIU Ming-bo, CHENG Da-wei and SHEN Xue-jing |Show fewer author(s)
Author Affiliations
  • [in Chinese]
  • show less

    During the detection process, the silicon drift detector (SDD) used in energy-dispersive X-ray fluorescence spectrometry will form escape peaks on the low-energy side of the solid characteristic peaks generated by the individual elements to be measured with high content, and the corresponding characteristic peaks are also will lose some strength, and the location of the escape peak is related to the composition of the detector. The energy difference between the incident characteristic peak and the escape peak in the SDD detector is 1. 739 keV, which is equal to the Kα characteristic energy of the silicon element. The intensity of the escape peak is proportional to the intensity of the incident X-ray, that is, proportional to the content of the corresponding element/characteristic peak intensity. The escape probability of the incident characteristic peak is usually low, and the influence on the test results is small when the escape peak intensity is low. It can be seen from theoretical calculations that the probability of generating escape peaks is related to the detector angle and element types, and with the increase of the incident characteristic line energy, the mass absorption coefficient of the silicon atom and the corresponding escape peak generation probability will also reduce. When the escape peak coincides with the characteristic energy peaks of other elements to be measured, it will interfere with the accurate measurement of the corresponding element, especially when the content of the element to be measured is low. The interference will be relatively more significant. Therefore, it is necessary to calculate and correct the escape peak accurately. In this paper, a corresponding platform is built for testing, and taking Fe and Mn elements as examples, through theoretical analysis and calculation of the escape peak probability in the SDD detector and compared with the escape probability value obtained from the actual test spectrum, it is found that the two data are in good agreement, and after the comparison it was found that the escape peak of Fe∶Kβ line in Fe2O3 sample overlapped with Cr∶Kα peak, and the escape peak of Fe∶Kα line partially overlapped with Ti∶Kα peak. After deducting the escape peak, Cr and Ti can be better analyzed for accurate quantification. This method can be extended to the calculation and correction of escape peaks of other elements with higher content, especially in the application of multi-element detection in samples with high content of individual elements such as soil, mineral, alloy detection, etc, and improve the test accuracy of X-ray fluorescence method.

    Tools

    Get Citation

    Copy Citation Text

    LIAO Xue-liang, LIU Ming-bo, CHENG Da-wei, SHEN Xue-jing. Analysis and Calculation of Escape Peaks in Silicon Drift Detectors[J]. Spectroscopy and Spectral Analysis, 2024, 44(5): 1297

    Download Citation

    EndNote(RIS)BibTexPlain Text
    Save article for my favorites
    Paper Information

    Received: Aug. 11, 2022

    Accepted: --

    Published Online: Aug. 21, 2024

    The Author Email: Xue-liang LIAO (851661195@qq.com)

    DOI:10.3964/j.issn.1000-0593(2024)05-1297-04

    Topics