Leakage and Reliability Characteristics of Lead Zirconate Titanate Thin‐Film Capacitors

Abstract

Resistance degradation in lead zirconate titanate (Pb(Zr,Ti)O3, PZT) thin‐film capacitors has been studied as a function of applied voltage, temperature, and film composition. The mean time‐to‐failure (lifetime, or tf) of the capacitors shows a power‐law dependence on voltage of the form tf∝V−n (n similar/congruent 4‐5). The capacitor lifetime also exhibits a temperature dependence of the form tf∝ exp[Ea/(kT)], with an activation energy of 0.6‐1.0 eV. The steady‐state leakage current in these samples seems to be bulk controlled. The voltage V, temperature T, and polarity dependence of the leakage current collectively suggest a leakage‐current mechanism that is most similar to a Frenkel‐Poole process. The tf value and the leakage current of niobium‐doped PZT films are superior to those of undoped PZT films. This result can be explained on the basis of the point‐defect chemistry of the PZT system. Finally, the results indicate that the niobium‐doped PZT films meet essential tf requirements for decoupling‐capacitor applications.

Effects of Nb doping on highly fatigue-resistant thin films of (Pb0.8Ba0.2)ZrO3 for ferroelectric memory application

“…The leakage current characteristic of the PBNZ films was then measured at room temperature. PBZ films which is in good agreement with the results of Nb-doped PZT films [14][15][16].…”

La Mn O 3 effects on the ferroelectric and magnetic properties of chemical solution deposited BiFeO3 thin films

“…Figure 4͑c͒ illustrates the linear regression fit of E a vs E 1/2 which on extrapolation leads to a trap depth of 0.94 eV. This trap depth is quite similar to what is generally found for lead-zirkonate-titanate ͑PZT͒ thin films, 14 and is generally ascribed to ionized oxygen vacancies. A slightly lower trap depth of 0.65 to 0.8 eV has been recently reported for epitaxial BFO films processed vial pulsed laser ablation 15 whereby conduction has been attributed to Fe 2+ species.…”

Leakage current behavior in lead-free ferroelectric (K,Na)NbO3-LiTaO3-LiSbO3 thin films

“…For this purpose, one way is to find ␣ in Figs. 3 and 4 based on Schottky and Poole-Frenkel emission, [19][20][21] as summarized in Table I, according to the following equations:…”