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

Abstract

Lead lanthanum zirconate titanate (PLZT) thin films were directly deposited on copper substrates by chemical solution deposition and crystallized at temperatures of ⩾650°C under low pO2 conditions. Although the crystallization conditions used are conducive for copper oxidation, a thin layer (∼115nm) of PLZT was sufficient to protect the underlying copper from oxidation. Films exhibited well saturated hysteresis loops with remanent polarization ∼24μC∕cm2 and dielectric constants ∼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.