碲锌镉(CdZnTe)晶体是一种新型核辐射探测材料,在室温探测环境下对X射线及低能量伽玛射线具有较高的探测效率及能量分辨率。运用低噪声快速前放模块,分析晶体内部性能以及前置放大器对探测系统噪声的影响,建立了2×2碲锌镉像素阵列探测系统。实验结果表明,探测系统输出信号噪声小、脉冲无堆积,读出电路电子学噪声得到明显抑制,能谱低能拖尾减少,电荷收集不完全噪声及漏电流噪声影响得到改善,同时对整个系统以及前置放大器进行了噪声分析并提出相关的改善方式,最后得到系统测试的结果。

As a novel nuclear radiation material, CdZnTe has many advantages of high efficiency detection and good energy resolution for detection of x-ray and low energy gamma-ray in room temperature. The inner crystal property and effects of preamplifier on the noise is analyzed using low noise preamplifier module, while a 2×2 array pixellated detection system is built. The results show a low noise of output signal and no pulse stack. The circuit electronic noise is obviously restrained. Trails of low power of energy spectrum are decreased. Noise analysis and the factors which produced the noise are given; improvement for the system is also discussed, together with the test result.