Electron microscopy characterization of Ba(Cd_(1/3)Ta_(2/3))O_3 microwave dielectrics with boron additive

摘要

The microstructure of Ba(Cd_(1/3)Ta_(2/3))O_3 ceramics with boron additive was investigated by high-resolution and analytical electron microscopy. Superlattice reflections were present at positions of (h +- 1/3, k +- 1/3, 1 +- 1/3) away from the fundamental reflections in the [110] zone diffraction pattern for the pseudocubic perovskite unit cell. Lattice images showed a well-ordered structure with hexagonal symmetry. No boron segregation and amorphous phase was observed along grain boundaries. An amorphous phase rich in boron-oxide was observed to form pockets partially penetrating along multiple grain junctions.