六方氮化硼的热中子辐照损伤  

Thermal neutron irradiation damage of hexagonal boron nitride

作　　者：阳永富 王柱[1] 陈万平[1] 邹武生 赵江滨[2] 何高魁[2] YANG Yongfu;WANG Zhu;CHEN Wanping;ZOU Wusheng;ZHAO Jiangbin;HE Gaokui(School of Physics and Technology,Wuhan University,Wuhan430072,China;China Institute of Atomic Energy,Beijing102413,China)

机构地区：[1]武汉大学物理科学与技术学院,湖北武汉430072 [2]中国原子能科学研究院,北京102413

出　　处：《电子元件与材料》2022年第7期691-698,共8页Electronic Components And Materials

基　　金：国家自然科学基金(11975169);国家自然科学基金(U2067207)。

摘　　要：由于辐照缺陷直接影响载流子收集效率和器件性能,辐照缺陷结构与六方氮化硼(hBN)中载流子产生和输运的关系一直是探测器研究的重要课题。利用静电计、X射线衍射(XRD)、正电子湮没寿命谱(PALS)等方法研究了热解氮化硼(PBN)和热压氮化硼(H-BN)材料的热中子辐照损伤和缺陷结构,以及辐照缺陷对载流子输运的影响。中子辐照的总剂量分别为3.9×10^(14),1.6×10^(15),1.0×10^(16) cm^(-2)。结果表明,中子辐照引入了大量的缺陷和杂质。缺陷的变化规律主要表现为单空位、双空位、小空位团缺陷浓度随着热中子辐照剂量的增加而增加。中子辐照产生的杂质(Li离子)成为了载流子产生中心。辐照引入的缺陷主要成为了载流子的散射和复合中心,降低了载流子迁移率和浓度,使得辐照后的载流子浓度远远低于预期的浓度。研究结果对于理解hBN中子探测器的载流子输运机理具有重要的科学意义。Since the irradiation defects directly affect the carrier collection efficiency and device performance,the relationship between the carrier generation and transport and the irradiation defect structure in hexagonal boron nitride(hBN)has always been an important area.The thermal neutron irradiation damage and defect structure,and the effect of irradiation defects on the carrier transport of pyrolytic boron nitride(PBN)and hot-pressed boron nitride(H-BN)irradiated with thermal neutron were investigated by the electrometer,X-ray diffraction(XRD),and positron annihilation lifetime spectroscopy(PALS).The total doses of neutron irradiation were 3.9×10^(14),1.6×10^(15),1.0×10^(16) cm^(-2),respectively.The results show that the neutron irradiation introduces numerous defects and impurities.The evolution of the defect structure is that the defect concentration of single vacancy,double vacancy,and small vacancy group increases with the increase of thermal neutron irradiation dose.The impurities(Li-ions)generated by neutron irradiation become the generation centers of the carriers.The defects introduced by the irradiation mainly become the scattering and recombination centers of the carriers,which reduces the carrier mobility and concentration,so that the carrier concentration after the irradiation is much lower than the expectation.The research results have important scientific significance for understanding the carrier transport mechanism of hBN neutron detectors.

关 键 词：六方氮化硼 中子辐照 缺陷 正电子湮没 载流子 

分 类 号：O474[理学—半导体物理]