Dipole engineering: Properties of In3+ and Ta5+ dipole substituted BaTiO3

Abstract

Dopants play a significant role in electronic material design. In semiconductors, donor and acceptor doping enhance electron and hole conduction, respectively, while simultaneously donor and acceptor doping counteract one another. The role of dopants versus substitutions within dielectrics are not as well studied nor are the effects as well understood. From semi-conductor theory dopant is addition of a small fraction of atoms, roughly less than one part in ten-thousand (to parts per million), and it is not a charge neutral process. In this investigation, the effects of dipole substitution of In and Ta within BaTiO3 are systematically investigated and frequency and temperature dependent dielectric properties are reported. Experimental data indicate that doping of In and Ta within BaTiO3 follows semiconductor theory; yet, dipole substitution reduces conductivity and results in the evolution of BaTiO3 from strict ferroelectric to diffuse phase transition to a relaxor-like ferroelectric within the formed solid solution Ba(In,Ta)yTi1-2yO3, 0 ≤ y ≤ 0.0375. This work of dipole dopant substitution within BaTiO3, provides generalized guidance for developing advanced (novel) materials.