Schottky barrier effects in the electronic conduction of sol–gel derived lead zirconate titanate thin film capacitors

Pure and Fe-doped Pb(Zr0.53Ti0.47)O3 (PZT) thin film capacitors were fabricated by the sol–gel method and the leakage current versus voltage characteristics of these films were investigated at several temperatures and initial polarization states. After the initial poling of ferroelectric thin films, we measured two kinds of leakage current: (i) the full-switching current measured against an initial polarization direction and (ii) the nonswitching current measured toward an initial polarization direction. In the case of the full-switching current measurement, the anomaly of leakage current due to the switching of space charges was observed, which we suggest to be accumulated at a Schottky barrier region near an electrode or a gain boundary. In the case of the nonswitching current measurement, the Schottky diode rectifier current and the field-enhanced Schottky (ES) emission current came out without the switching current. The Poole–Frenkel emission process was dominant over ES emission for a Fe-doped PZT th...

[1]  C. Hu,et al.  A ferroelectric DRAM cell for high-density NVRAMs , 1990, IEEE Electron Device Letters.

[2]  Robert E. Jones,et al.  A model for electrical conduction in metal‐ferroelectric‐metal thin‐film capacitors , 1994 .

[3]  H. Grubin.  The physics of semiconductor devices , 1979, IEEE Journal of Quantum Electronics.

[4]  J. T. Evans,et al.  An experimental 512-bit nonvolatile memory with ferroelectric storage cell , 1988 .

[5]  D. M. Smyth.  Charge motion in ferroelectric thin films , 1991 .

[6]  S. B. Krupanidhi,et al.  Current-voltage characteristics of ultrafine-grained ferroelectric Pb(Zr, Ti)O_3 thin films , 1994 .

[7]  C. Cho,et al.  Fatigue effects of metal-doped PZT thin films , 1996 .

[8]  T. Mihara,et al.  Evaluation of Imprint Properties in Sol-Gel Ferroelectric Pb(ZrTi)O3 Thin-Film Capacitors , 1993 .

[9]  Characterization and modelling of thin-film ferroelectric capacitors using C-V analysis , 1992 .

[10]  S. Dey,et al.  Electrical Properties of Paraelectric (Pb 0.72La 0.28)TiO3 Thin Films with High Linear Dielectric Permittivity: Schottky and Ohmic Contacts , 1995 .

[11]  S. Dey,et al.  Dopant compensation mechanism and leakage current in Pb(Zr0.52, Ti0.48)O3 thin films , 1996 .

[12]  A. Sigov,et al.  MICROELECTRONIC APPLICATIONS OF FERROELECTRIC FILMS , 1993 .

[13]  G. Arlt,et al.  Maxwell-wagner relaxation and degradation of SrTiO3 and BaTiO3 ceramics , 1986 .

[14]  A. Kingon,et al.  Characterization of conduction in PZT thin films produced by laser ablation deposition , 1993 .

[15]  T. Ikeda,et al.  Optical Study of Lead Zirconate-Titanate , 1965 .

[16]  Michael Sayer,et al.  Preparation of Pb(Zr,Ti)O3 thin films by sol gel processing: Electrical, optical, and electro‐optic properties , 1988 .

[17]  R. Zuleeg,et al.  Quantitative measurement of space-charge effects in lead zirconate-titanate memories , 1991 .