一种基于热释电效应的X射线荧光分析谱仪

摘要

利用热释电晶体实现了一个X射线激发源 ,并以此激发源和高能量分辨率的硅漂移探测器构建了一个X射线荧光分析谱仪.首先通过分析计算热释电晶体厚度和靶厚度对产生X射线的影响选定了激发源的设计参数 ;然后测量了激发源发射的X射线本底 ,其能量范围在1~27 keV ,包含有Cu和Ta的特征X射线 ,最大强度在每秒3 000个计数以上 ,对本底的测量同时显示出谱仪的探测器部分对Cu的8.05 keV特征峰的分辨率达到210 eV ,具有很高的能量分辨率 ;最后使用该谱仪测试了Fe ,Ti和Cr等三种单质样品和高钛玄武岩样品 ,测试结果表明该谱仪可以有效的分析出样品的元素成分.由于这种X射线荧光分析谱仪的各组成部分体积都很小 ,进一步便携化后非常适合于非破坏、现场和快速的元素分析场合.%Pyroelectric X-ray generator is implemented ,and an X-ray fluorescence spectrometer is accomplished by combining the pyroelectric X-ray generator with a high energy resolution silicon drift detector .Firstly ,the parameters of the X-ray generator are decided by analyzing and calculating the influence of the thickness of the pyroelectriccrystal and the thickness of the target on emitted X-ray .Secondly ,the emitted X-ray is measured .The energy of emitted X-ray is from 1 to 27 keV ,containing the char-acteristic X-ray of Cu and Ta ,and the max counting rate is more than 3 000 per second .The measurement also proves that the detector of the spectrometer has a high energy resolution which the FWM H is 210 eV at 8.05 keV .Lastly ,samples of Fe ,Ti , Cr and high-Ti basalt are analyzed using the spectrometer ,and the results are agreed with the elements of the samples .It shows that the spectrometer consisting of a pyroelectric X-ray generator and a silicon drift detector is effective for element analysis .Ad-ditionally ,because each part of the spectrometer has a small volume ,it can be easily modified to a portable one which is suitable for non-destructive ,on-site and quick element analysis .