Diffusion of Sr and Zr in BaTiO 3 single crystals

Abstract

The diffusion of strontium and zirconium in single crystal BaTiO 3 was investigated in air at temperatures between 1000 °C and 1250 °C. Thin films of SrTiO 3, deposited by spin coating a precursor solution and thin films of zirconium, deposited onto the sample surfaces by sputtering, were used as diffusion sources. The diffusion profiles were measured by SIMS depth profiling on a time-of-flight secondary ion mass spectrometer (ToF-SIMS). The diffusion coefficients of strontium and zirconium were given by D Sr = 3.6 × 10 2.0±4.4 exp[−(543 ± 117) kJ mol −1/( RT)] cm 2 s −1 and D Zr = 1.1 × 10 1.0±2.1 exp[−(489 ± 56) kJ mol −1/( RT)] cm 2 s −1. The results are discussed in terms of different diffusion mechanisms in the perovskite structure of BaTiO 3.