高能离子梯度多剂量辐照4H-SiC的微结构及硬度变化研究  

Study on Microstructure and Hardness Changes of 4H-SiC Irradiated by High Energy Ion Gradient with Multiple Doses

作　　者：吕康源 张崇宏[1,2] 张宪龙 韩旭孝 陈宇光 宋银 LÜKangyuan;ZHANG Chonghong;ZHANG Xianlong;HAN Xuxiao;CHEN Yuguang;SONG Yin(Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China;School of Nuclear Science and Technology,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]中国科学院大学核科学与技术学院,北京100049

出　　处：《原子核物理评论》2022年第4期533-538,共6页Nuclear Physics Review

基　　金：国家自然科学基金资助项目(11575263,U1532262)。

摘　　要：为探讨高温高能离子辐照碳化硅后的结构和力学性能随剂量的变化,应用拉曼光谱和纳米压痕技术研究了122 MeV的^(20)Ne^(4+)离子梯度多剂量辐照后的4H-SiC。研究表明,SiC的相对拉曼强度随剂量的增大呈指数规律下降,并出现了代表无序化Si-C键和同核Si-Si键的散射峰。基于DI/DS模型的初步拟合表明,在低剂量范围内扩展缺陷簇是引起SiC无序化的主要因素,高剂量范围内的无序化则是由离子直接碰撞过程的非晶化和扩展缺陷簇共同引起。辐照后的SiC硬度取决于位错钉扎和共价键断裂的共同作用,在0~4.00 dpa之间硬度随剂量增大而增大,在4.00~8.05 dpa之间硬度随剂量增大而减小,剂量在8.05 dpa时,硬度相比于未辐照区域略高,此时共价键断裂和位错钉扎达到平衡。In order to investigate the changes of structure and mechanical properties of silicon carbide irradiated by high energy ions,the 4H-SiC after 122 MeV ^(20)Ne^(4+)ion gradient multi-dose irradiation was investigated by Raman spectrum and nano indentation technology.The Relative Raman Intensity of the sample decreases exponentially with the increase of dose,and there are scattering peaks representing disordered Si-C bond and homonuclear Si-Si bond.Preliminary fitting based on the DI/DS model shows that the expansion of defect clusters in the low dose range is the main factor causing the disorder,while the disorder in the high dose range is caused by amorphization in the process of direct ion collision and extended defect clusters.The hardness of irradiated silicon carbide is the joint action between dislocation pinning and covalent bond breaking.Between 0~4.00 dpa,the hardness increases with the increase of dose,and between 4.00~8.05 dpa,the hardness decreases with the increase of dose.At 8.05 dpa,the hardness is slightly higher than that unirradiated area.At the same time,the covalent bond breaking and dislocation pinning reach equilibrium.

关 键 词：拉曼光谱 纳米压痕技术 相对拉曼强度 

分 类 号：O433.4[机械工程—光学工程]