The present overview describes the evolution of new microdosimeters developed in the National Microelectronics Center in Spain (IMB-CNM, CSIC), ranging from the first ultra-thin 3D diodes (U3DTHINs) to the advanced 3D cylindrical microdetectors, which have been developed over the last 10 years. In this work, we summarize the design, main manufacture processes, and electrical characterization of these devices. These sensors were specifically customized for use in particle therapy and overcame some of the technological challenges in this domain, namely the low noise capability, well-defined sensitive volume, high spatial resolution, and pile-up robustness. Likewise, both architectures reduce the loss of charge carriers due to trapping effects, the charge collection time, and the voltage required for full depletion compared to planar silicon detectors. In particular, a 3D‒cylindrical architecture with electrodes inserted into the silicon bulk and with a very well‒delimited sensitive volume (SV) mimicked a cell array with shapes and sizes similar to those of mammalian cells for the first time. Experimental tests of the carbon beamlines at the Grand Accélérateur National d’Lourds (GANIL, France) and Centro Nazionale Adroterapia Oncologica (CNAO, Italy) showed the feasibility of the U3DTHINs in hadron therapy beams and the good performance of the 3D‒cylindrical microdetectors for assessing linear energy distributions of clinical beams, with clinical fluence rates of 5 × 10⁷ s⁻¹cm⁻² without saturation. The dose-averaged lineal energies showed a generally good agreement with Monte Carlo simulations. The results indicated that these devices can be used to characterize the microdosimetric properties in hadron therapy, even though the charge collection efficiency (CCE) and electronic noise may pose limitations on their performance, which is studied and discussed herein. In the last 3D‒cylindrical microdetector generation, we considerably improved the CCE due to the microfabrication enhancements, which have led to shallower and steeper dopant profiles. We also summarize the successive microdosimetric characterizations performed with both devices in proton and carbon beamlines.

中文翻译：

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强子疗法中用于微量剂量测定的硅3D微探测器

本概述介绍了西班牙国家微电子中心（IMB-CNM，CSIC）开发的新型微剂量计的发展，从最早的超薄3D二极管（U3DTHIN）到先进的3D圆柱形微检测器，这些检测器是在西班牙开发的。最近十年 在这项工作中，我们总结了这些设备的设计，主要制造工艺和电气特性。这些传感器是专门为用于颗粒治疗而定制的，克服了该领域的一些技术难题，即低噪声能力，明确定义的灵敏体积，高空间分辨率和堆积坚固性。同样，两种架构都可以减少由于陷阱效应，电荷收集时间，与平面硅探测器相比，完全耗尽所需的电压。特别是，一种3D圆柱结构，其中电极插入硅块中，并且具有非常精确界定的敏感体积（SV），首次模拟了形状和大小类似于哺乳动物细胞的细胞阵列。在法国国家最高的AccélérateurNational d'Lourd实验室和意大利的Centro Nazionale Adroterapia Oncologica的碳束线进行的实验测试表明，U3DTHIN在强子治疗束中的可行性以及3D圆柱形微探测器的良好性能评估临床光束的线性能量分布，临床注量率为5×10 3D圆柱结构，其中电极插入硅块中，并且具有非常精确界定的敏感体积（SV），首次模仿了形状和大小类似于哺乳动物细胞的细胞阵列。在法国国家最高的AccélérateurNational d'Lourd实验室和意大利的Centro Nazionale Adroterapia Oncologica实验室的碳束线实验表明，U3DTHIN在强子束中的可行性以及3D圆柱形微探测器的良好性能评估临床光束的线性能量分布，临床注量率为5×10 3D圆柱结构，其中电极插入硅块中，并且具有非常精确界定的敏感体积（SV），首次模仿了形状和大小类似于哺乳动物细胞的细胞阵列。在法国国家最高的AccélérateurNational d'Lourd实验室和意大利的Centro Nazionale Adroterapia Oncologica实验室的碳束线实验表明，U3DTHIN在强子束中的可行性以及3D圆柱形微探测器的良好性能评估临床光束的线性能量分布，临床注量率为5×10⁷ s ^-1 cm ^-2不饱和。剂量平均线形能量与蒙特卡洛模拟显示出良好的一致性。结果表明，即使电荷收集效率（CCE）和电子噪声可能对其性能造成限制，但这些设备仍可用于表征强子治疗中的微剂量特性，本文对此进行了研究和讨论。在最后的3D圆柱型微型检测器中，由于微加工的增强，我们大大改善了CCE，这导致了更浅和更陡的掺杂剂分布。我们还总结了在质子和碳束线中使用这两种设备进行的连续微剂量学表征。