Comparison of Cavities Formed in Single Crystalline and Polycrystalline α-SiC after H Implantation

Abstract

Cavities and extended defects formed in single crystalline and polycrystalline α-SiC implanted with H+ ions are compared. The samples are investigated by cross-sectional transmission electron microscopy. H2 bubbles are formed during H implantation and H2 molecules escape the sample to form cavities during thermal annealing at 1100°C. Microcracks and the extended defects prefer to nucleate in single crystalline α-SiC, but not polycrystalline α-SiC. Grain boundaries can account for the experimental results. The formation of cavities on grain boundaries is investigated.