The retention of krypton in polycrystalline silicon during high-temperature annealing

In a study into the annealing behaviour of silicon containing a few atomic per cent of krypton, it was found that, even at 0.87 of the silicon melting temperature, approximately 90% of the original krypton was still present. This result is compared with analogous work on metals where copious inert gas release occurs at homologous temperatures below about 0.7 of the melting point. The marked retention efficiency in silicon is consistent with its anomalously low concentration of thermal vacancies.