Defect-mediated ferroelectric domain depinning of polycrystalline BiFeO3 multiferroic thin films
Defect-mediated ferroelectric domain depinning of polycrystalline BiFeO3 multiferroic thin films
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DOI：
10.1063/1.4867703
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发表时间：
2014-03
影响因子：
4
通讯作者：
Í. Bretos;R. Jiménez;Carmen Gutiérrez-Lázaro;I. Montero;M. Calzada
中科院分区：
文献类型：
--
作者：
Í. Bretos;R. Jiménez;Carmen Gutiérrez-Lázaro;I. Montero;M. Calzada
采用二次再氧化退火驱动的缺陷扩散机制，研究了多晶BiFeO3薄膜的铁电畴脱蚀过程。从薄膜的电流-电压（I-V）特性讨论了导致钉住的缺陷复合物（氧空位偶极子）的存在。这些配合物通过再氧化退火解离产生材料中有效的区域脱屑。由于Fe2+向Fe3+的价态变化，在再氧化态释放的氧空位得到补偿。畴迁移率的提高对铁电开关的贡献更大，室温剩余极化为67 μC cm−2。
The ferroelectric domain depinning in a polycrystalline BiFeO3 film is studied by a defect-mediated diffusion mechanism driven by a secondary re-oxidation anneal. The presence of defect complexes (oxygen-vacancy-associated dipoles) responsible for pinning is discussed from the current-voltage (I-V) characteristics of the film. Dissociation of these complexes by re-oxidation anneal produces the effective depinning of domains in the material. The released oxygen vacancies would be compensated at the re-oxidized state due to the valence change of Fe2+ to Fe3+. Improvement on domain mobility results in a larger contribution to ferroelectric switching, showing a room-temperature remanent polarization of 67 μC cm−2.