Electrical Properties for Capacitors of Dynamic Random Access Memory on (Pb, La)(Zr, Ti)O_3 Thin Films by Metalorganic Chemical Vapor Deposition (<Special Issue> FERROELECTRIC MATERIALS AND THEIR APPLICATIONS)

概要

論文の詳細を見る
Lanthanum-modified lead zirconate titanate (PLZT) thin films (0.2-0.35 μm) have been prepared on Pt/SiO_2/Si substrates at 650℃ by the metalorganic chemical vapor deposition (MOCVD) method. The electrical properties of the films were examined as a function of lanthanum content in the range of 0-22 at. %. The remanent polarization and coercive field decreased as the La content increased in the range of 0-14 at. %, whereas they were maintained at constant values of 1 μC/cm^2 and 20 kV/cm, respectively, even in the paraelectric region where La content exceeds 15 at. % in ceramics. The effective dielectric constant of 1200 was obtained at La=10 at. %, and the effective charge densities were about 30 fF/μm^2 when La=8-22 at. %. It has been suggested that the breakdown of the films does not occur up to about 1×10^<15> cycles at an access voltage of 3 V by the unipolar acceleration test.
社団法人応用物理学会の論文
1994-09-30