会议专题

PROPERTY UNIFORMITY AND POLING BEHAVIOR OF PMN-PT CRYSTAL GROWN BY VERTICAL GRADIENT FREEZE METHOD

3-inch diameter PMN-PT ingots were grown along 001 direction using Vertical Gradient Freeze (VGF) method.Wafers are sliced,sequentially numbered and tested for the study of property distribution along the ingot,and samples from the same wafer were studied for in-wafer uniformity.As a result,001 grown and poled PMN-PT crystals typically have electromechanical coupling coefficient k33 higher than 0.91,and free relative permittivity between 4,600 and 7,500,varying monotonically along the ingot,due to PT composition segregation.In-wafer free relative permittivity variation coefficient is measured within 2%,due to sufficient agitation during growth.It is also shown that piezoelectric properties saturate around 350 kV/mm for PMN-0.29PT and 250 kV/mm for PMN-0.31PT,respectively.Both PMN-0.29PT and PMN-0.31PT experience property degradation due to over-poling over 1300 kV/mm,and PMN-0.31PT is more susceptible to over-poling due to closer vicinity to the Morphotropic Phase Boundary (MPB).It is thought that over-poling is a field-induced phase transition and such transition is found reversible by annealing at certain elevated temperatures.

PMN-PT Vertical Gradient Freeze Uniformity Segregation Overpoling Annealing

Zi-bo JIANG

Innovia Materials(Shanghai)Co., Ltd, Shanghai 201210, China

国际会议

The 2016 Symposium on Piezoelectricity,Acoustic Waves and Device Applications(2016全国压电和声波理论及器件技术研讨会)

西安

英文

447-451

2016-10-21(万方平台首次上网日期,不代表论文的发表时间)