Oxygen-related dielectric relaxation and leakage characteristics of Pt/(Ba,Sr)TiO[sub 3]/Pt thin-film capacitors.

The leakage characteristics and dielectric properties of Pt/(Ba,Sr)TiO[sub 3]/Pt thin-film capacitors were found to be remarkably sensitive to the postannealing temperature in oxygen and nitrogen atmosphere. High leakage currents and low-frequency dielectric relaxation were found in as-deposited capacitors after they had been postannealed in nitrogen at 550 °C and subsequently annealed in oxygen at 350 °C. Such results are related to the mobile oxygen ions and oxygen vacancies accumulated in the (Ba,Sr)TiO[sub 3] films. The chemical process of the formation of charged oxygen ions during postannealing is proposed. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]