H 2 O vapor-induced leakage degradation of Pb(Zr,Ti)O3 thin-film capacitors with Pt and IrO2 electrodes

We have investigated the influence of H2O vapor on the leakage characteristics of Pb(Zr,Ti)O3 (PZT) thin-film capacitors with Pt and IrO2 top electrodes by conducting electrical measurements ex situ in air and in situ in an 80% N2/20% O2 atmosphere with controlled humidity ranging from <0.1% to 95.5% relative humidity at 20 °C. The results show that the leakage characteristics of PZT thin-film capacitors are strongly sensitive to H2O vapor in the atmosphere. The onset to H2O-induced leakage degradation depended on the relative humidity and on the quantity of charge passed through the capacitor. A degradation mechanism based on the electrolysis of H2O that has adsorbed on the capacitor from the atmosphere and the role of the electrode material in the degradation process are discussed.