Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment ( IF 1.5 ) Pub Date : 2020-05-08 , DOI: 10.1016/j.nima.2020.164116 O. Grimm , M. Bednarzik , G. Birrer , V. Commichau
This paper reports on the performance changes in CdTe:Cl semiconductor X-ray detectors seen after irradiation with 50 MeV protons up to a fluence of 1.61011cm−2. The rationale for the irradiation parameters is described. Performance was quantified before and after irradiations by obtaining X-ray spectra with a barium-133 radioactive source and detectors cooled to −20°C. Energy resolutions, electron and hole drift lengths, and energy calibration parameters were extracted by fitting model spectra to the data. Ten crystals of dimension 10101 mm3 were used, with two each being irradiated to 20%, 40%, 60%, 80%, and 100% of the maximum fluence. Each crystal is pixelized and the eight large pixels of area 9.6 mm2 are analysed separately to allow estimation of uncertainties.
The main observations are a strong decrease of the electron drift length and an increase of the electronic noise with fluence. The hole drift length shows a tendency to increase with fluence. A basic interpretation of some observations in terms of an increasing density of acceptor trap levels with fluence is given.
中文翻译:
质子辐照CdTe X射线传感器的探测特性变化
本文报道了用50 MeV质子辐照至1.6的注量辐照后CdTe:Cl半导体X射线探测器的性能变化10 11厘米-2。描述了照射参数的原理。通过使用钡133放射源和冷却至-20°C的检测器获得X射线光谱来量化辐照前后的性能。通过将模型光谱拟合到数据中来提取能量分辨率,电子和空穴漂移长度以及能量校准参数。十个尺寸为10的晶体10使用1 mm 3,分别以最大通量的20%,40%,60%,80%和100%照射两个。每个晶体都被像素化,分别分析面积为9.6 mm 2的八个大像素,以估计不确定性。
主要观察结果是电子漂移长度的强烈减小和电子能量随通量的增加。空穴漂移长度显示出随着通量增加的趋势。给出了一些观察结果的基本解释,即随着通量的增加,受体陷阱水平的密度增加。