Dielectric Properties of Sol-Gel Derived Pb(Mg_1/3Nb_2/3)O₃–PbTiO₃ Thin Films

Abstract

Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 (PMN-PT) thin films were fabricated using a sol-gel method. The dielectric constant was found to be strongly dependent on the number of strong Mg–O–Nb bonds in the precursor solution. A large number of strong Mg–O–Nb bonds were formed after a long reflux time. This process resulted in PMN thin films with a large dielectric constants sometimes greater than 3000, with a loss tangent of 0.5%. Relaxor characteristics such as weak temperature dependence and weak dc bias dependence were also observed in the thin films. These results suggest that PMN-PT is an important material for thin film capacitor applications.