A study of vacancy-related defects in (Pb,La)(Zr,Ti)O/sub 3/ thin films using positron annihilation

摘要

The formation of vacancy-type defects in La-doped lead zirconate titanate (PLZT) thin films (Zr/Ti=20/80) was studied as a function of lanthanum doping and after cooling in an oxygen-reduced ambient. The changes in the Doppler-broadening S parameter are consistent with the progressive introduction of Pb-vacancies upon La-doping. Cooling of PLZT thin films with 0 and 10% La doping in 10/sup -5/ Torr oxygen partial pressure after growth exhibits an increase in the density of vacancy-type defects compared to films cooled in 760 Torr. It is proposed that the defects formed are likely cation-oxygen vacancy complexes.