TIME-DEPENDENT AND TRAP-RELATED CURRENT CONDUCTION MECHANISM IN FERROELECTRIC PB(ZRXTI1-X)O-3 FILMS

The correlation between trap density and leakage current of Pb(Zr53Ti4 7)O-3 (PZT) capacitors is studied by examining the current-time (I-t) and the current-voltage (I-V) characteristics. The increase of leakage current after de electrical field stress is correlated with the numbe r of charges trapped inside the films. The spatial density distributio n of trapped charges is calculated by analyzing the decay of dischargi ng current after the application of de stress. The discharging current is well fitted by a 1/t relationship where t is discharging time. Thi s behavior can be explained by using the tunneling front model. A disc harging process is proposed based on this consideration. (C) 1996 Amer ican Institute of Physics.