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81.
82.
Gd掺杂对PZT薄膜介电性能及极化行为的影响 总被引:2,自引:0,他引:2
采用sol-gel法在Pt/Ti/SiO2/Si衬底上制备出高度(100)择优取向的Gd掺杂PZT薄膜(简写为PGZT); 介电测试结果表明, 1mol%Gd掺杂的PZT薄膜介电常数最大, 2mol%Gd掺杂PZT薄膜与未掺杂薄膜的介电常数相差不大, Gd掺入量>2mol%时, 薄膜的介电常数下降; 薄膜的不可逆极化值呈现与介电常数相同的变化趋势, 而可逆极化值变化较小. 在弱电场下(低于矫顽场Ec), 用瑞利定律分析薄膜介电常数随电场强度的变化规律, 1mol%Gd掺杂的薄膜瑞利系数α最大, 说明薄膜中缺陷的浓度最低. 1mol%Gd掺杂的薄膜介电和铁电性能的改善与Gd3+在PZT晶格中的占位情况有关. 相似文献
83.
用胶体化学的方法获得PZT溶胶,利用LB技术制备PZT超细陶瓷微粒/硬脂酸复合LB膜,热处理后得到PZT超薄膜.由π-A曲线确定了具体的拉膜工艺参数和条件,由紫外-可见吸收光谱和AFM照片对复合LB膜和超薄膜进行表征和性能检测.结果表明:超薄膜中PZT超微粒排布较均匀,覆盖度较高;复合膜层均匀,在194 nm和256 nm处均有较强的吸收峰. 相似文献
84.
As the introduction of piezoelectric materials into micro electromechanical systems increases, there is a correlating requirement for understanding the mechanical properties of these films. We have investigated the mechanical properties of unpoled PZT [Pb(Zr,Ti)O3] and PMNT [Pb(Mg1/3Nb2/3)1−xTixO3] thin films deposited by sputtering. In this study, nano-indentation, a technique which allows determination of the transverse mechanical properties, is used. It is the easiest method for assessing the biaxial elastic modulus and the hardness of thin films. It was confirmed that neither cracks, nor pile-ups, were observed for indentation depths below 20% of the film's thickness.The continuous stiffness method was used and allowed us to demonstrate that the indentation modulus decreases continuously with increasing grain diameter. This can be explained by the orientation changes of the crystallites with increasing grain diameter. The indentation modulus measured under load, or at almost null load (that is when the ferroelectric domains are or are not oriented by the stress) are coherent with those determined by the same method with a hard bulk ceramic. These results tend to show that the compliance Cij of the hard bulk ceramic can possibly be used with sputtered thin films. The hardness is almost independent of the grain diameter (Hb ≅ 7.5 ± 0.9 GPa) and higher than that for the bulk PZT ceramics considered in this study. PMNT and PZT films have appreciably the same mechanical characteristics. No influence of the film thickness was found on the values of both of these parameters. 相似文献
85.
86.
用Sol-Gel法制备了Pb(Zr_(0.5)Ti_(0.5))O_3(PZT)铁电陶瓷与薄膜,观察了它们的结晶情况并测定了它们的电学性能。利用Sol-Gel法,可降低PZT陶瓷粉料的预烧温度约200℃,所得陶瓷致密,晶粒均匀;具有较好的介电性能。PZT陶瓷显示弥散相变特征。PZT薄膜的晶化受基底影响很大。基底晶格越完整,与PZT薄膜的晶格失配率越小,PZT薄膜的晶化就越好。采用PbTiO_3过渡层促进PZT薄膜在镀铂硅片上晶化。PbTiO_3过渡层与PZT薄膜构成串联电路。其表现电学性能与相应的PZT体材料相近。 相似文献
87.
Seok Han KimSridhar Komarneni 《Ceramics International》2011,37(8):3211-3216
Various parameters such as gel composition, aging, organic additive, and heating method affected the preferred orientation of nearly cubic PZT particles that were prepared by hydrothermal methods using TiCl3 as a Ti3+ source, at relatively low temperatures of 100-140 °C. The newly found synthetic conditions could be used to develop specially orientated PZT particles, which may be useful in growing oriented films, for example, by electrophoretic deposition. 相似文献
88.
《Ceramics International》2016,42(6):6782-6790
Phase pure lead zirconate titanate (PZT) powder was produced via a new aqueous coprecipitation method. A suite of characterization techniques, including FTIR, Raman, X-ray diffraction, SEM as well as nitrogen sorption were employed to investigate the structural evolution of the synthesized and calcined powder. The dried precipitate formed in aqueous phase yielded approximately 80 wt% final product after calcination. The PZT perovskite structure was obtained after calcination at 550 °C for 3 h. Milling of the calcined powder reduced the mean particle size from approximately 10 µm to 2 µm. With increasing calcination temperature from 550 °C to 700 °C, both surface area and pore volume decreased while pore size increased from 3.4 nm to 9.8 nm. The bulk density of pelletized samples increased from 4.83 to 7.57 g/cm3 with increasing sintering temperature from 800 °C to 1200 °C. Powder processing using this aqueous route is simple and reproducible leading to a method that is readily scalable for industrial applications. 相似文献
89.
Effects of pore size and orientation on dielectric and piezoelectric properties of 1-3 type porous PZT ceramics 总被引:1,自引:0,他引:1
Porous PZT ceramics have drawn an increasing amount of interest in recent years due to their superior properties compared with the dense material. However, researchers have usually dedicated effort to 0-3 and 3-3 type porous PZT ceramics and little attention has been focused on 1-3 type. The 1-3 type porous PZT ceramics with high porosity were fabricated in this study by freeze-casting process. All samples possessed high piezoelectric coefficient (d33) with high porosity owing to the special one-dimensional ordered porous structure along the poling direction. The d33 values increased by either improving the pore channel orientation level or decreasing pore size. The relative permittivity improved only with the enhancement of pore channel orientation level. The acoustic impedances ranged from 1.45 to 1.35 MRayls which could match well with those of biological tissue or water; therefore, this material would be beneficial in hydrophone applications. 相似文献
90.
D. Kajewski P. Zajdel A. Soszyński J. Koperski I. Lazar K. Roleder 《Ceramics International》2019,45(8):9871-9877
Lead zirconate-titanate PbZr0.70Ti0.30O3 ceramics doped with bismuth oxide has been investigated. Dielectric and optical measurements were performed to check the dopant influence on phase transitions and pre-transitional effects. It has been postulated that the temperature at which maximum permittivity occurs is not connected with structural phase transitions. 相似文献