Scanning force microscopy of relaxor ferroelectric PbMg _1/3Nb_2/3O₃-PbTiO₃ thin films for piezoelectric sensors

Relaxor ferroelectric PbMg_1/3Nb_2/3O ₃-PbTiO₃ (PMN-PT) thin films were grown by a sol-gel method. By using scanning force microscopy, piezoelectric poling and imaging were studied in a number of regions on the films with subsequent statistical analysis of the obtained data. Piezoresponse and poling behavior appear to have a relation with relaxor behavior of the materials, which is defined as frequency-dependent phase transition in ferroelectric materials. Hysteresis loops are observed when an external field is swept, regardless of vibration frequency of the bias, indicating relaxation behavior of the PMN-PT films.