New silicon 3-D-microdetectors have been developed to perform microdosimetry measurements for applications in hadron therapy. In this work, the charge collection efficiency (CCE) of an improved second generation of microdetectors having two different thicknesses (10 and 20 $\mu \text{m}$ ) and a diameter of 25 $\mu \text{m}$ has been studied by means of the ion beam induced charge (IBIC) technique. New methods to study the active volume and the CCE of microdosimeters are proposed and verified here. The results show that, for this new generation of microdetectors, the CCE is 100% for radial distances up to 10.2 $\mu \text{m}$ from the center of the device, and it rapidly decays between 10.2 $\mu \text{m}$ and the detector edge. The characterization of the CCE conducted here will allow us to completely explain the energy spectra obtained during the microdosimetry studies performed in clinical centers.

中文翻译：

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硅3-D检测器中用于微剂量测定的电荷收集效率的表征

已开发出新型硅3-D微型探测器来执行强子疗法中的微剂量测量。在这项工作中，具有两种不同厚度（10和20）的改进的第二代微型探测器的电荷收集效率（CCE） $ \ mu \ text {m} $ ），直径为25 $ \ mu \ text {m} $ 已通过离子束感应电荷（IBIC）技术进行了研究。在此提出并验证了研究微量剂量计有效体积和CCE的新方法。结果表明，对于新一代的微型探测器，径向距离最大为10.2时，CCE为100％ $ \ mu \ text {m} $ 从设备中心开始，它在10.2之间迅速衰减 $ \ mu \ text {m} $ 和检测器边缘。此处进行的CCE表征将使我们能够完全解释在临床中心进行的微量剂量学研究期间获得的能谱。