中子辐照6H-SiC晶体中的钉扎效应

Pinning Effect of the Neutron-irradiated 6H-SiC Crystals

分别对两种不同的6H-SiC晶体进行了总通量为5.74×1018n.cm-2、8.2×1018n.cm-2和1.72×1019n.cm-2的不同剂量的中子辐照,利用X射线衍射等手段观测了中子辐照引起的晶体内部损伤。结果表明:两种样品在不同的中子通量辐照下,消除部分原始缺陷的、纯度较高的样品辐照后的内部损伤明显小于纯度较低、内部原始缺陷较多的样品。样品的辐照损伤不仅取决于中子辐照剂量,还取决于其辐照时的成分和结构。晶体的结构缺陷和杂质,作为一种"钉扎",在辐照过程中作用极大,它们导致了晶体的长程缺陷(如位错)的大幅度增加。

Two different 6H-SiC single crystals were neutron-irradiated with different dose of 5.74×10^18n·cm^2 ,8.2×10^18n·cm^-2and 1.72× 10^19 n·cm^2 respectively, the damages caused by neutron irradiation were studied by X-ray diffraction. It is found that the damages in the samples with higher purity or in the on the irradiation fluences, but also are decided on the structure and the composition of the samples. The inherent defects and the impurity atom play an important role in the irradiation process as the ＂pinning＂, which result in the increasing of the long-range defects such as dislocations.