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Clustering of vacancy defects in high-purity semi-insulating SiC

R. Aavikko·K. Saarinen·F. Tuomisto·B. Magnusson·N. T. Son·E. Janzen
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Abstract

Positron lifetime spectroscopy was used to study native vacancy defects in semi-insulating silicon carbide. The material is shown to contain (i) vacancy clusters consisting of 4--5 missing atoms and (ii) Si vacancy related negatively charged defects. The total open volume bound to the clusters anticorrelates with the electrical resistivity both in as-grown and annealed material. Our results suggest that Si vacancy related complexes compensate electrically the as-grown material, but migrate to increase the size of the clusters during annealing, leading to loss of resistivity.

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R. Aavikko, K. Saarinen, F. Tuomisto, B. Magnusson, N. T. Son, E. Janzen. 2006-06-06. Clustering of vacancy defects in high-purity semi-insulating SiC. https://doi.org/10.1103/physrevb.75.085208

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