中文摘要：

半导体探测器具有优异的性能因而被广泛应用于能量色散X射线荧光测量,以传统型Si-PIN半导体探测器与复合型CdTe半导体探测器为研究对象,分别从材料属性、探测效率、能量分辨率等方面对两种探测器进行对比,重点分析探测器灵敏区厚度、入射X射线能量、后级电路成型时间等因素对其性能的影响,并对由逃逸峰、空穴拖尾效应所导致的X射线荧光能谱的差异进行分析;同时,针对探测器空穴收集不完全的问题,基于FPGA设计了带有上升时间甄别功能的数字多道脉冲幅度分析器,能够有效消除空穴拖尾的影响,提高能量分辨率。从实验结果可知：对能量低于15keV的射线,Si-PIN与CdTe探测器的探测效率基本相当;对能量大于15keV的射线,CdTe探测器的的探测效率明显占优;Si-PIN探测器的最佳成形时间约为10μs,CdTe探测器的最佳成形时间约为2.6μs,因而CdTe探测器更适用于高计数率条件;对于不同能量的X射线,Si-PIN探测器的能量分辨率优于CdTe探测器;CdTe探测器具有明显的空穴拖尾效应,将CdTe探测器与带上升时间甄别功能的数字多道脉冲幅度分析器配合使用,其能量分辨率显著提高。

英文摘要：

Semiconductor detector is widely used in energy dispersive X-ray fluorescence measurementsdue to its excellent performance.In this paper,Si-PIN and CdTe semiconductor detectors were studied,performances of the two detectors were compared in material properties,detection efficiency,energy resolution and other aspects.Focused on the performance of the detectors influenced by the thickness of detector sensitive area,energy of incident X-ray,shaping time of post-stage circuit,and analyzed the differences of energy spectrum caused by escape peaks and hole trailing.Aiming at the problem of incomplete hole collection in detector,a digital multi-channel analyzer（DMCA）based on FPGA with rise-time discriminator was designed,it could reduce the influence of hole trailing effectively and improve energy resolution.The experimentation results indicate that the detection efficiency of Si-PIN and CdTe is roughly equal when energy is below 15 keV while CdTe has much higher detection efficiency than Si-PIN when energy is above 15 keV.The optimum forming time of the Si-PIN detector is about 10μs,and the CdTe detector is about 2.6μs,so the CdTe detector is more suitable for the high count rate condition.Si-PIN detector has better energy resolution than CdTe detector for different energy incident X-ray.CdTe detector has obvious hole tailing effect and the energy resolution of CdTe detector is significantly improved by using DMCA with rise-time discrimination.