论文部分内容阅读
在陶瓷基底上利用电子束蒸镀方法制备了Si薄膜,用作感应读出方式光子计数成像系统的电荷感应层,并研究了薄膜的结构特征和表面形态.X射线衍射(XRD)测试和场发射扫描电子显微镜(FESEM)图像表明,沉积的Si薄膜为无定形态,由于陶瓷晶界的存在,薄膜较粗糙.搭建了相应的实验系统,对比了采用不同厚度Si薄膜时系统的空间分辨率、计数率、脉冲高度分布曲线等,发现薄膜的厚度对探测器的计数率影响较大.此外,实验还对比了采用相同电阻值的Si薄膜和常用的Ge薄膜时系统的性能.研究表明,采用Si薄膜时系统的畸变较小、计数率高、暗计数小。
Si films were prepared by electron beam evaporation on a ceramic substrate and used as a charge sensing layer in an induction readout photon counting imaging system. The structural characteristics and surface morphology of the films were also investigated. X-ray diffraction (XRD) The emission scanning electron microscopy (FESEM) image shows that the deposited Si film is in an amorphous state, and the film is coarse due to the existence of the ceramic grain boundaries. The corresponding experimental system is set up, and the spatial resolution of the system is compared with Si films with different thicknesses , The counting rate, the pulse height distribution curve and so on, it is found that the thickness of the film has a great influence on the counting rate of the detector.In addition, the experiment also compares the performance of the Si film with the same resistance and the common Ge film, When the Si film is used, the distortion of the system is small, the count rate is high, and the dark count is small.