Dependence of Thermally Stimulated Current in PZT Film Capacitors on PZT-Electrode Interface

• Published in: Ferroelectrics Vol. 357; no. 1; pp. 243 - 247
• Main Authors: Nishida, Takashi, Takeda, Takashi, Uchiyama, Kiyoshi, Shiosaki, Tadashi
• Format: Journal Article Conference Proceeding
• Language: English
• Published: London Taylor & Francis Group 28.09.2007; Taylor and Francis
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric thin films; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Domain structure; hysteresis; Exact sciences and technology; Ferroelectricity and antiferroelectricity; interface and crystalline defects; Physics; PZT film; Thermally stimulated current; Buffer layer; Interface defect; Defect density; interface and crystalline defects; PZT film; Inorganic compounds; Thermostimulated conduction; Capacitors; Lead titanates; Transition element compounds; Measuring methods; PZT; Heat treatments; Lead zirconates; Thickness; Thermally stimulated current; Secondary ion mass spectra; Ferroelectric materials; Depth profiles; Ferroelectric hysteresis
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/00150190701545342

It is known that crystalline defects in Pb(Zr, Ti)O 3 (PZT) film devices cause degradation in performance, and consequently, the evaluation of the defects and development of their measurement methods are important. Thermally stimulated current (TSC) measurement is one of the methods, and has been used to evaluate semiconductor and organic materials. However, investigation of TSC for ferroelectric film such as PZT has not been carried out sufficiently. We have, in previous work, evaluated the influence of composition and interface of the top electrode on TSC, however, the dependence on the interface of the bottom electrode has not been investigated, even though high density crystalline defects are formed at the interface by the heating during PZT deposition. In this study, TSC measurements of the PZT films deposited on buffer layers of various thicknesses were carried out, and the dependence on the bottom interface was evaluated. From the experimental results, the peak at 250°C in the TSC profile increased with excess lead contents at the interface, and it was revealed that crystalline defects at the bottom interface can also be evaluated by the TSC measurement.