Effect of hydrogen on true leakage current characteristics of (Pb,La)(Zr,Ti)O 3 thin-film capacitors with Pt- or Ir-based top electrodes

• Published in: Journal of materials research Vol. 16; no. 4; pp. 1185 - 1189
• Main Authors: Yoon, Soon-Gil, Wicaksana, Dwi, Kim, Dong-Joo, Kim, Seung-Hyun, Kingon, A. I.
• Format: Journal Article
• Language: English
• Published: 01.04.2001
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/JMR.2001.0163

The degradation behavior of polarization and leakage current characteristics of sol-gel-derived (Pb,La)(Zr,Ti)O 3 (PLZT) thin films, with Pt, Ir, and IrO 2 top electrodes, by annealing under a 4% H 2 /96% N 2 atmosphere were investigated. The leakage current behaviors of Pt/PLZT/Pt and IrO 2 /PLZT/Pt capacitors annealed at 300 °C for 20 min in 4% H 2 were well consistent with the space-charge-influenced injection model proposed. However, IrO 2 /PLZT/Pt capacitors recovered at 700 °C for 10 min in Ar ambient after hydrogen anneal were not consistent with the proposed model because a conducting phase of IrPb was formed between the top electrode and PLZT during the recovery anneal at 700 °C in Ar ambient and modified the Schottky barrier height. The true leakage current behavior of IrO 2 /PLZT/Pt capacitors recovered after hydrogen forming are similar to those of Ir/PLZT/Pt capacitors without the hydrogen-forming gas anneal. The P – E loops of Pt/PLZT/Pt and Ir/PLZT/Pt capacitors showed good recovery through recovery anneal after H 2 treatment. However, IrO 2 /PLZT/Pt capacitors depended on the recovery anneal atmosphere (Ar or O 2 ).