六方氮化硼辐照缺陷的正电子研究

近年发展的由六方氮化硼（h-10BN或h-BN）制成的中子探测器，是目前固态中子探测器中热中子探测效率最高的中子探测器。但在探测中子的同时，六方氮化硼遭遇到中子辐射，产生杂质和缺陷，并影响探测器性能。本项目拟通过正电子湮没技术,特别是符合多普勒展宽谱，理论计算（缺陷构型、寿命、多普勒展宽谱和S参数）、并结合PL谱、拉曼光谱、光电子能谱、霍尔效应、热脱附谱等方法，研究原生的,电子辐照或自离子辐照的,He离子、Li离子辐照的，以及退火处理的h-BN材料中的缺陷结构。鉴定缺陷的种类、浓度、荷电状态、亚晶格和空位-杂质复合体。探索特定的杂质和缺陷分布对载流子迁移率和寿命的影响。本项目对预测六方氮化硼（h-10BN或h-BN）制成的热中子探测器的性能衰减，提高热中子探测器的缺陷修复能力和使用寿命具有重要的科学意义和实用价值。

The neutron detector made of hexagonal boron nitride (h-10BN or h-BN) developed in recent years is the most efficient neutron detector for thermal neutron detection in solid state neutron detectors. However, while detecting neutrons, hexagonal boron nitride is exposed to neutron radiation, resulting in impurities and defects, and affecting the performance of the detector. This project intends to study defect structures in as-grown, electron or self-ion irradiated, He ion and Li ion irradiated h-BN with positron annihilation technology, especially Doppler broadening spectrum, theoretical calculation (defect configuration, positron lifetime, Doppler broadening spectrum of annihilation radiation and S, W parameters), combined with PL spectroscopy, Raman spectroscopy, photoelectron spectroscopy, Hall effect and thermal desorption spectroscopy. The types, concentrations, charged states, sublattices and vacancy-impurity complexes of defects in h-BN materials are also identified. The effects of specific impurities and defect distribution on carrier mobility and lifetime are explored. This project has important scientific significance and practical value for predicting the performance attenuation of thermal neutron detectors made of hexagonal boron nitride (h-10BN or h-BN), improving the defect repair ability and service life of thermal neutron detectors.