Repelling effects of Mg on diffusion of He atoms towards surface in SiC: Irradiation and annealing experiments combined with first-principles calculations  

作　　者：Min Liu Qiqi Li Jun Hui Yongfeng Yan Renduo Liu Biao Wang 

机构地区：[1]Sino-French Institute of Nuclear Engineering and Technology,Sun Yat-sen University,Zhuhai 519082,China [2]School of Materials Science and Engineering,Dongguan University of Technology,Dongguan 523000,China [3]Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China

出　　处：《Journal of Advanced Ceramics》2023年第12期2284-2299,共16页先进陶瓷（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.12175323 and 11705264);Guangdong Basic and Applied Basic Research Foundation(Grant No.2023A1515012692);the National Natural Science Foundation of China Original Exploration Project(Grant No.12150001);the Project of Nuclear Power Technology Innovation Center of Science Technology and Industry for National Defense(Grant No.HDLCXZX-2021-HD-035).

摘　　要：In this study,the effects of Mg on the formation of He bubbles and diffusion behavior of He atoms in cubic silicon carbide(3C–SiC)were investigated by irradiation and annealing experiments as well as first-principles calculations.TEM results indicated that two damage bands were formed in He&Mg irradiated SiC.During annealing,Mg could prevent He atoms from diffusing to the surface,resulting in the formation of the He bubbles in the deeper areas far from Mg-implanted regions,which is helpful in avoiding surface blisters.First-principles calculations were then performed to explore the effects of Mg on the He behavior in SiC.The solution energy,binding energy charge density,bond length,and crystal orbital Hamiltonian population of these elements were calculated to identify their states.The results suggested that the binding capacity between He and Mg was weak,and Mg could increase the diffusion energy barrier of He.Ab initio molecular dynamics(AIMD)simulation showed that Mg could make He in a high-energy unstable state,and force He atom to move toward the vacancy away from Mg,which explains the experimental results.

关 键 词：SIC IRRADIATION He bubbles Mg ab initio molecular dynamics(AIMD) 

分 类 号：TQ174.758.12[化学工程—陶瓷工业]