Deposition of sol-gel derived lead lanthanum zirconate titanate thin films on copper substrates

Lead lanthanum zirconate titanate (PLZT) thin films were directly deposited on copper substrates by chemical solution deposition and crystallized at temperatures of >= 650 degrees C under low pO(2) conditions. Although the crystallization conditions used are conducive for copper oxidation, a thin layer (similar to 115 nm) of PLZT was sufficient to protect the underlying copper from oxidation. Films exhibited well saturated hysteresis loops with remanent polarization similar to 24 mu C/cm(2) and dielectric constants similar to 730. Indirect evidence suggests that the oxygen vacancies created during the high temperature processing are responsible for the degradation of the electrical properties of these thin films. Techniques for avoiding this problem are proposed. (c) 2008 American Institute of Physics.