Stabilizing Perovskite Pb(Mg_0.33Nb_0.67)O₃–PbTiO₃ Thin Films by Fast Deposition and Tensile Mismatched Growth Template

High Resolution Image Download MS PowerPoint Slide Because of its low hysteresis, high dielectric constant, and strong piezoelectric response, Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 (PMN–PT) thin films have attracted considerable attention for the application in PiezoMEMS, field-effect transistors, and energy harvesting and storage devices. However, it remains a great challenge to fabricate phase-pure, pyrochlore-free PMN–PT thin films. In this study, we demonstrate that a high deposition rate, combined with a tensile mismatched template layer can stabilize the perovskite phase of PMN–PT films and prevent the nucleation of passive pyrochlore phases. We observed that an accelerated deposition rate promoted mixing of the B-site cation and facilitated relaxation of the compressively strained PMN–PT on the SrTiO 3 (STO) substrate in the initial growth layer, which apparently suppressed the initial formation of pyrochlore phases. By employing La-doped-BaSnO 3 (LBSO) as the tensile mismatched buffer layer, 750 nm thick phase-pure perovskite PMN–PT films were synthesized. The resulting PMN–PT films exhibited excellent crystalline quality close to that of the STO substrate.