Wang Yuli, Herbst Ryan, Abbaszadeh Shiva
Department of Electrical and Computer Engineering, University of California Santa Cruz, Santa Cruz, CA 95064, USA.
SLAC National Accelerator Labratory, 2575 Sand Hill Road, Menlo Park, CA, USA.
IEEE Trans Radiat Plasma Med Sci. 2022 May;6(5):517-521. doi: 10.1109/trpms.2021.3111547. Epub 2021 Sep 10.
Cadmium zinc telluride (CZT) detectors are suitable for various applications due to the good energy resolution and the simple pixilation to achieve high spatial resolution. Our group is developing a two-panel head and neck dedicated positron emission tomography system based on CZT detectors. Each panel will consist of 150 CZT crystals (4×4×0.5 cm) covering an area of 20×15 cm in an edge-on configuration to achieve high detector efficiency at 511 keV. In this work, we present the design and development of a full data acquisition chain that enables a low noise and compact readout for each panel. The initial results of the readout circuit were quantified using a 1 kHz square wave test pulse. The pulse amplitude was chosen to generate approximately the same amount of charges as a 511 keV photon would provide in CZT. The best-case FWHM electronic noise at 511 keV was measured to be 0.69% ± 0.16% (3.52 ± 0.81 in keV units after conversion). The FWHM electronic noise at 511 keV for a complete DAQ chain was 4.33% ± 0.30% (22.13 ± 1.53 in keV units).
碲锌镉（CZT）探测器由于具有良好的能量分辨率以及易于像素化以实现高空间分辨率，适用于各种应用。我们的团队正在开发一种基于CZT探测器的双面板头颈部专用正电子发射断层扫描系统。每个面板将由150个CZT晶体（4×4×0.5厘米）组成，以边缘配置覆盖20×15厘米的面积，以在511 keV下实现高探测器效率。在这项工作中，我们展示了一个完整数据采集链的设计与开发，该采集链能够为每个面板实现低噪声和紧凑的读出。读出电路的初始结果使用1 kHz方波测试脉冲进行了量化。选择脉冲幅度以产生与511 keV光子在CZT中提供的电荷量大致相同的电荷量。在511 keV下测量的最佳情况半高宽电子噪声为0.69%±0.16%（转换后以keV为单位为3.52±0.81）。完整数据采集链在511 keV下的半高宽电子噪声为4.33%±0.30%（以keV为单位为22.13±1.53）。
