Mn-doped PMN-PT thin films for electrocaloric applications

摘要

In this work, lead magnesium niobate-lead titanate (1-x)Pb(MgNb)O-xPbTiO ((1-x)PMN-xPT) thin films with PT-fractions of 6.5 to 20% were fabricated on Pt(111)-coated Si wafers by multi-target reactive sputtering using four metallic targets (Pb, Mg, Nb, Ti). In order to increase the dielectric strength, co-doping with Mn was performed by co-sputtering of MnO targets. The electrocaloric temperature change ΔTEC was estimated using Maxwell's relation. Additionally, the EC coefficient ΔT/ΔE was evaluated by integrating the electric field dependence of the pyroelectric coefficient determined by a high-frequency laser intensity modulation method.