High‐Temperature Hall Measurements on BaSnO 3 Ceramics

Simultaneous Hall and conductivity measurements were performed in situ between 650° and 1050°C on n‐type semiconducting BaSnO 3 ceramics. The variation of the Hall mobility and the Hall carrier density as a function of oxygen partial pressure between 10 2 and 10 5 Pa and of temperature was investigated. At temperatures below 900°C the conductivity exhibits a dependence on temperature and oxygen partial pressure which is mainly determined by variations of the Hall mobility. Above 900°C most of the significant dependence is due to a variation in carrier density. Furthermore, a simple defect model assuming doubly ionized oxygen vacancies and acceptor impurities is discussed for BaSnO 3 .