新型弛豫铁电晶体PIN-PT的单晶生长与性能表征  

Growth and Performance Characterization of Novel Relaxor-based Ferroelectric Crystal PIN-PT

作　　者：方义权 赵学洋[1] 柯毅阳[1] 向军涛[1] 胡旭波[1] 魏冉[1] 王敏刚[1] 陈红兵[1] 

机构地区：[1]宁波大学材料科学与工程研究所,新型功能材料及其制备科学国家重点实验室培育基地,宁波315211

出　　处：《人工晶体学报》2014年第10期2503-2508,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(21171102);浙江省重大科技计划优先主题(2009C11144);宁波大学王宽诚幸福基金

摘　　要：按照0.65Pb(In1/2Nb1/2)O3-0.35PbTiO3的计量组成,应用高温固相分步合成方法制备出钙钛矿相PIN-PT多晶料,采用熔体坩埚下降法生长出尺寸φ20 mm×50 mm的PIN-PT晶体毛坯。采用XRD、DTA/TG对PIN-PT晶体的结晶物相与热学性能进行了分析表征,测试了(111)取向PIN-PT晶片样品的介电温谱、压电常数和电滞回线。结果表明所生长晶体毛坯呈现具有显著特征的结晶相分布,即晶体毛坯中间部分为钙钛矿相而外围部分出现焦绿石相,且钙钛矿相晶体呈现沿晶体毛坯轴向逐渐发育生长趋势;取自晶体毛坯中上部的晶片基本为四方相,其(111)取向晶片的压电常数d33~415 pC/N,机电耦合系数k33~37.5%,室温介电常数ε~3095,介电损耗tanδ~1.0%,居里温度达266℃,矫顽电场Ec^11.04 kV/cm,剩余极化Pr^21.07μC/cm2。According to the composition ratio of 0. 65Pb（ In1 /2Nb1 /2） O3-0. 35PbTiO3,PIN-PT polycrystalline material with perovskite phase was synthesized by solid-state reaction with two-steps. PINPT crystal boule with size of 20 mm × 50 mm were grown from the polycrystalline material by meltsBridgman method. The crystallographic phase and thermal properties of the crystals were characterized by XRD and DTA /TG analysis. The electrical parameters of（ 111） orientation PIN-PT crystal wafer,i. e.the temperature dependence of dielectric permittivity,piezoelectric constant and ferroelectric hysteresis loop,were measured systematically. The results show a characteristics of crystallographic phase distribution in the crystal boule,i. e. the perovskite phase,surrounded by pyrochlore phase,is distributed along the boule axis with a tendency to grow gradually in the crystal growth. The wafers fabricated from the middle to up region of as-grown crystal boule was verified to be tetragonal phase basically. The crystal wafer with（ 111） orientation exhibits a dielectric constant ε - 3095 and dielectric loss tanδ - 1. 0% at room temperature with a high Curie temperature of 266 ℃. The piezoelectric andferroelectric parameters were measured as piezoelectric permittivity d33- 415 pC /N,electromechanical coupling factor k33- 37. 5%,the coercive field Ec- 11. 04 kV /cm and remanent polarization Pr- 21. 07μC/cm^2.

关 键 词：弛豫铁电晶体 PIN-PT 晶体生长 熔体坩埚下降法 电学性能 

分 类 号：O77[理学—晶体学]