Structural and electrical characterization of lead metaniobate thin films deposited by pulsed laser ablation

Abstract

Lead niobate thin films have been prepared by laser ablation, at different substrate temperatures (Tdep) and with different oxygen pressures (pO2). For low deposition temperatures the films presented a rhombohedric-PbNb2O6 structural phase, with hysteresis cycles characteristic of a paraelectric. As Tdep increased the films started to develop an orthorhombic- PbNb2O6 structure that appeared at 400ºC and remained up to 600ºC. For low pO2, a mixture of this phase and a lead deficient phase was present in the films. Increasing the oxygen pressure the lead deficient phase was strongly reduced and the films presented only the ferroelectric orthorhombic- PbNb2O6 structural phase.