Cross-sectional investigation is an important method to study ion irradiation effects in the depth direction. In this study, 2 Me V H^+was implanted in 6 H-SiC single crystals to investigate the effects of light ion i...Cross-sectional investigation is an important method to study ion irradiation effects in the depth direction. In this study, 2 Me V H^+was implanted in 6 H-SiC single crystals to investigate the effects of light ion irradiation on SiC. Raman spectroscopy and scanning electronic microscopy(SEM) were carried out on crosssectional samples to reveal the in-depth damage states and dopant behavior. The most damaged region is a little shallower than that predicted by the SRIM procedure,owing to the uncertainty in SRIM simulations. Layered structures representing zones of varying damage after2 MeV H ion irradiation are clearly observed. Two bands are observed in SEM images, of which on band corresponds to the damage peak, while the other band at the end of the H ion-affected area is probably a result of H diffusion propelled by a hydrogen-rich layer during irradiation.A charge accumulation effect related with conductivity on the sample surfaces during SEM tests is observed in theH-implanted area. A model is proposed to explain these phenomena.展开更多
The Fe78Si8B14 and Fe78P8B14 ribbons with different wheel speeds were prepared by melt-spinning, and their responses to He+ ion irradiation were investigated. Previous studies had shown that the ion beam resistance c...The Fe78Si8B14 and Fe78P8B14 ribbons with different wheel speeds were prepared by melt-spinning, and their responses to He+ ion irradiation were investigated. Previous studies had shown that the ion beam resistance capability of amorphous ribbons was better than their corresponding crystalline counterparts. However, no significant changes on the surface at low fluence are observed. At a relatively higher fluence, both the ribbons prepared at low and high wheel speeds behave the similar irradiation responses: peeling, flaking and multi-layer damages occur. The fully amorphous ribbons prepared at a high wheel speed can accommodate partial incident ions owing to the inherent disordered structure. As the irradiation fluence increases, they fail to accommodate the excess incident ions, which easily aggregate to result in the surface damage. While the partial amorphous ribbons prepared at a low wheel speed possess lots of unstable crystalline grain boundaries owing to the precipitation of Si-or P-rich phase, which may act as the source for the irradiation-induced defects annihilation. Results show that the size and the fraction of precipitate phases in amorphous matrix may play a dominated role in resisting the ion irradiation.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.11705169,91426304 and 91226202)
文摘Cross-sectional investigation is an important method to study ion irradiation effects in the depth direction. In this study, 2 Me V H^+was implanted in 6 H-SiC single crystals to investigate the effects of light ion irradiation on SiC. Raman spectroscopy and scanning electronic microscopy(SEM) were carried out on crosssectional samples to reveal the in-depth damage states and dopant behavior. The most damaged region is a little shallower than that predicted by the SRIM procedure,owing to the uncertainty in SRIM simulations. Layered structures representing zones of varying damage after2 MeV H ion irradiation are clearly observed. Two bands are observed in SEM images, of which on band corresponds to the damage peak, while the other band at the end of the H ion-affected area is probably a result of H diffusion propelled by a hydrogen-rich layer during irradiation.A charge accumulation effect related with conductivity on the sample surfaces during SEM tests is observed in theH-implanted area. A model is proposed to explain these phenomena.
基金Acknowledgements The authors would like to acknowledge the support by the National Natural Science Foundation of China (Grant Nos. 51401028, 51271193, 11402277) and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB22 040303). The authors also thank to the support of Opening Fund of State Key Lab of Nuclear Physics and Technology at Peking University.
文摘The Fe78Si8B14 and Fe78P8B14 ribbons with different wheel speeds were prepared by melt-spinning, and their responses to He+ ion irradiation were investigated. Previous studies had shown that the ion beam resistance capability of amorphous ribbons was better than their corresponding crystalline counterparts. However, no significant changes on the surface at low fluence are observed. At a relatively higher fluence, both the ribbons prepared at low and high wheel speeds behave the similar irradiation responses: peeling, flaking and multi-layer damages occur. The fully amorphous ribbons prepared at a high wheel speed can accommodate partial incident ions owing to the inherent disordered structure. As the irradiation fluence increases, they fail to accommodate the excess incident ions, which easily aggregate to result in the surface damage. While the partial amorphous ribbons prepared at a low wheel speed possess lots of unstable crystalline grain boundaries owing to the precipitation of Si-or P-rich phase, which may act as the source for the irradiation-induced defects annihilation. Results show that the size and the fraction of precipitate phases in amorphous matrix may play a dominated role in resisting the ion irradiation.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 11175203 and 91126002) the Strategic Priority Research Program of Chinese Academy of Sciences (Grant Nos. KJCX2-YW-N35 and XDA03010303) and the National Magnetic Confinement Fusion Program (Grant No. 2011GB 108004).