Observation of He bubbles in ion irradiated fusion materials by conductive atomic force microscopy

• Published in: Journal of nuclear materials Vol. 441; no. 1-3; pp. 54 - 58
• Main Authors: Fan, Hongyu, Li, Ruihuan, Yang, Deming, Wu, Yunfeng, Niu, Jinhai, Yang, Qi, Zhao, Jijun, Liu, Dongping
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2013; Elsevier
• Subjects: Applied sciences; Bubbles; Controled nuclear fusion plants; Diffusion; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Internal pressure; Irradiation; Mathematical analysis; Nanostructure; Nuclear fuels; Silicon carbide; Swelling; Nuclear fusion reactor; Silicon carbide; Swelling; Pressure; Nuclear reactor
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2013.05.034

Using a non-destructive conductive atomic force microscope combined with the Ar+ etching technique, we demonstrate that nanoscale and conductive He bubbles are formed in the implanted layer of single-crystalline 6H-SiC irradiated with 100keV He+. We find that the surface swelling of irradiated SiC samples is well correlated with the growth of elliptic He bubbles in the implanted layer. First-principle calculations are performed to estimate the internal pressure of the He bubble in the void of SiC. Analysis indicates that nanoscale He bubbles acting as a captor capture the He atoms diffusing along the implanted layer at an evaluated temperature and result in the surface swelling of irradiated SiC materials.