极化调控PIN-PMN-PT铁电单晶压电性能的均匀性  

Uniformity of Piezoelectric Properties of PIN-PMN-PT Ferroelectric Single Crystals Modulated by Polarization Technique

作　　者：梁敏 熊瑞彬 陈淑丽 王祖建[3] 苏榕冰[3] 苏彬 刘颖[1,2,3] 何超[3] LIANG Min;XIONG Ruibin;CHEN Shuli;WANG Zujian;SU Rongbing;SU Bin;LIU Ying;HE Chao(School of Rare Earths,University of Science and Technology of China,Hefei 230026,China;Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou 341119,China;Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences,Fuzhou 350002,China)

机构地区：[1]中国科学技术大学稀土学院,合肥230026 [2]中国科学院赣江创新研究院,赣州341119 [3]中国科学院福建物质结构研究所,福州350002

出　　处：《人工晶体学报》2024年第6期953-958,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(12275274,52172009,52102011);福建省工业引导项目(2021H0043);中国科学院青年培育项目(JCPYJJ-22032);中国科学院青促会(2022330)。

摘　　要：弛豫铁电单晶具有优异的压电性能,在医学超声换能器、水声器件等领域有重要应用。坩埚下降法生长的弛豫铁电单晶不可避免地存在组分偏析,导致材料利用率极低。本工作测试了0.24PIN-0.46PMN-0.30PT铁电单晶沿生长方向压电系数(d_(33))和介电常数(ε_(33)^(T)/ε_(0))的变化,结果显示d_(33)和ε_(33)^(T)/ε_(0)沿着生长方向变化极大,能保持性能接近的区域不足20 mm。通过针对不同区域的极化设计,对铁电-铁电相变温度接近的区域进行极化调控,使超过60%晶体部分的d_(33)和ε_(33)^(T)/ε_(0)分别维持在(1500±140)pC·N-1和4900±350。为了验证极化调控后的晶体谐振区域是否一致,测试了两端区域的k_(33)振子的谐振谱,结果显示两者的机电耦合系数接近,谐振和反谐振的峰位置也接近,而且不存在额外的寄生振动,说明采用极化调控PIN-PMN-PT铁电单晶沿生长方向的均匀性是可行的。本工作为提高PIN-PMN-PT铁电单晶的利用率提供了一种参考方案。Relaxor ferroelectric single crystals have important applications in medical ultrasound transducers,hydroacoustic devices and other fields due to their excellent piezoelectric properties.The relaxor ferroelectric single crystals grown by the Bridgman method inevitably suffers from component segregation,resulting in extremely low utilization.In this work,the variation of piezoelectric coefficient(d_(33))and dielectric constant(ε_(33)^(T)/ε_(0))of 0.24PIN-0.46PMN-0.30PT ferroelectric single crystals along the growth direction were tested.The results show that d_(33) andε_(33)^(T)/ε_(0)are extremely variable along the growth direction,with less than 20 mm of the region maintaining close performance.Polarization modulations were applied in different regions with close ferroelectric-ferroelectric phase transition temperatures through different polarization designing.The d_(33) andε_(33)^(T)/ε_(0)of more than 60%region of the crystalline maintain in the range of(1500±140)pC·N-1 and 4900±350,respectively.In order to verify the consistency of the resonance peaks of the crystal after polarization modulation,the resonance spectra of the k_(33) vibrators in the two end regions were tested.The results show that the electromechanical coupling coefficients are close to each other,and the peak positions of resonance and anti-resonance are also close to each other.Importantly,there don’t exist additional spurious-mode vibrations.These demonstrate the feasibility of employing polarizationmodulation to regulate the uniformity of the PIN-PMN-PT ferroelectric single crystals along the growth direction.This work provides a reference solution to improve the utilization of PIN-PMN-PT ferroelectric single crystals.

关 键 词：PIN-PMN-PT 铁电单晶 极化调控 组分分凝 压电系数 

分 类 号：O78[理学—晶体学] O738