Nuclear reaction analysis of helium migration in silicon carbide

作者：Miro S^*; Costantini J M; Haussy J; Beck L; Vaubaillon S; Pellegrino S; Meis C; Grob J J; Zhang Y; Weber W J

来源：Journal of Nuclear Materials, 2011, 415(1): 5-12.

DOI：10.1016/j.jnucmat.2011.05.009

4H-SiC and 6H-SiC single crystals were implanted at room temperature with 3-MeV (3)He ions at a fluence of 1 x 10(16) cm(-2). Analysis of helium migration was carried out with the (3)He(d, p)(4)He nuclear reaction. No clear thermally-activated migration in the end-of-range (EOR) region is found below 1100 degrees C, meaning that helium is strongly trapped probably in helium-vacancy clusters. At 1100 degrees C and above, a fraction of (3)He atoms remains trapped in the clusters, but a significant fraction is detrapped into a broad distribution, which is slightly shifted towards the sample surface. Helium detrapping from the EOR region increases with increasing annealing time and temperature. Moreover, the helium content is not conserved, since a significant fraction of 3He atoms is released out of the sample. Helium out-gassing actually increases with increasing annealing time and temperature, up to about 40% at 1150 degrees C. No clear difference is found between the 4H-SiC and 6H-SiC polytypes.

• 出版日期2011-8-1
• 单位中国地震局