新型高效率固体中子探测材料与器件的实验研究

Neutrons and their related technologies play an ever important role in basic science research as well as many application areas including defence, nuclear technologies, and anti-terrorisim. But neutron detection is still based upon mostly gaseous detection techniques. The proposed project will investigate the interaction of neutron beams with solid interfaces with different configuration and use systematic computer simulations to confirm optimal solid-state interface configuration.We will then use boron to construct an adsorption layer coated on the semiconducting p-n junction, combined with nanotechnology, to form indirect semiconductor neutron detector; the adsorption layer-junction interface is designed following the optimum configuration determined in the simulation. In the meantime, we will investigate the properties of boron carbide and use the material to build direct semiconductor neutron detector using the same strategy of optimizing the geometry of the depletion layer. We will further study the mechanisms of identifying the locations of incoming neutron beams and their directions by coincident measurements of the individual p-n junctions with aim to form spatial neutron images. The work performed in this project focus on studying and resolving a series of key issues in fundamental physics, materials, and electronic technology through investigating the interaction of neutron beams with solid interfaces and the nature of novel solid neutron capture materials and developing a novel high efficiency, high-resolution, easy-to-integrate, solid-state neutron detector with high performance-price ratio, to meet the requirements of basic science and technology application.

中子的应用在基础科学和前沿高科技领域包括国防，核技术，反恐和先进医学手段起着越来越重要的作用,而中子探测仍基本停滞在气体探测器的技术基础上。本项目将研究中子与各种构型的固体界面的相互作用，根据利用优化界面的理念、系统的理论计算和模拟，来确定半导体pn 结和中子俘获层的最佳固体界面构型，然后利用中子俘获截面高的硼材料作为俘获层，结合纳米技术，研制附有硼俘获层和最佳界面构型的间接型半导体中子探测器。同时，我们将研究碳硼半导体的性质并根据同样优化界面理念研制基于碳硼半导体的pn结和直接型中子探测器。我们将进一步研究多个pn的复合关联测量以提高中子探测器的空间分辨率为实现三维中子空间成像打下基础。本项目将解决一些有关中子-物质相互作用合中子探测的关键性问题，研制出高灵敏度，高效率，可集成化的新型固体中子探测器。

中子的应用在基础科学和前沿高科技领域包括国防，核技术，反恐和先进医学手段起着越来越重要的作用，而中子探测仍基本停滞在气体探测器的技术基础上。.本项目研究组根据利用优化界面的理念、系统的理论计算和模拟，建立起完整的模拟中子与各种材料、各种几何结构的计算机软件系统，模拟结果显示，硅孔洞正三角密排的探测器的探测效率最高，细致模拟了该构型下探测器的各种几何参数（厚度、中子孔洞直径、孔洞间距、孔洞深度等），为新型固体中子探测器的设计指明了方向；设计并搭建了基于高阻抗谱仪的精密测量平台，测量中子探测器中材料和器件的电荷迁移速度，表征了中子探测器中材料和器件的相关参数；基于石英晶体振荡器，提出了一种固气界面沉积膜粘弹性参数的计算方法，测量固气界面聚乙烯醇缩丁醛薄膜粘弹性进而确定其玻璃化转变温度及其随厚度和剪切频率变化趋势；给出了液相下石英晶体微天平输出信号和晶体表面吸附质量之间正比关系的方程，探究液相下石英晶体微天平输出信号的物理意义；基于石英晶体微天平技术，测量了固液界面孤立态柔性聚合物的构象和动力学参数及其与聚合物浓度、分子量、聚合物分子-界面之间距离的关系，细致研究固液界面对附近孤立态柔性聚合物分子的构象、动力学性质的影响；研究了有机分子玻璃化转变点自由体积和脆度的关系。.由此，解决一些有关中子-物质相互作用和中子探测的关键性问题，研制出高灵敏度，高分辨率，高效率，高度易于集成化的新型固体中子探测器。