Stress conditions transition by thermal annealing in barium zirconate based proton conducting thin films fabricated using PLD method

Barium zirconate based proton conducting thin films were fabricated using PLD method with ArF Excimer laser under high and low oxygen partial pressures on silicon wafers, and stress conditions and its transition by thermal annealing were measured by XRD side inclination method. Stress conditions were changed by thermal annealing, and two stress transition modes were observed. Stress condition in the films deposited at high oxygen partial pressure was compressive and the value was changed to tensile by thermal annealing. Considering the difference of thermal expansion coefficient, stress condition due to thermal stress was tensile. Therefore, this transition was defined as stress relaxation. By contrast, the films deposited at low oxygen partial pressure showed tensile stress condition, and transited to compressive stress condition, i.e. stress increment. These two modes were probably due to the transition of intrinsic stress caused by surface energy, which was sensitive to the deposition atmospheres.