Detection of oxygen vacancies in (Pb,La)(Zr,Ti)O3thin film capacitors using positron annihilation

The detection of oxygen vacancies by positron annihilation techniques in selected perovskite-type oxide thin films is reviewed. The basic principles of this defect characterization method, applied to thin films, are introduced. The capability of the method is illustrated for ferroelectric Pb(Zr,Ti)O3 (PZT) and conducting oxide La(Sr,Co)O3 (LSCO) thin films. Its use in obtaining oxygen vacancy defect distribution profiles in La doped PZT (PLZT) capacitor structures, LSCO/PLZT/LSCO, exposed to different oxygen ambient process conditions, is also reviewed. The observed changes in the oxygen vacancy concentration are correlated with the polarization-voltage hysteresis loops measurements.