Crystallography of faceted boundaries in SrTiO3 electronic ceramics

Faceted boundaries in SrTiO₃ electronic ceramics have been studied using transmission electron microscopy. A number of orientation relationships were observed in both SrTiO₃ internal boundary layer capacitor ceramics (IBLCs) doped with either sodium or lithium as an acceptor and niobium as a donor and a SrTiO₃ semiconducting ceramic doped only with niobium. Dislocation contrast appearing in such boundaries suggested that faceting was most evident in boundaries free of intergranular films.