优化的溶胶-凝胶法制备多层铁电-铁磁纳米复合薄膜(英文)

Characterization of Ferroelectric-Ferromagnetic Multilayered Nanocomposite Films Using a Modified Sol-Gel Process

在溶胶-凝胶的前驱体中加入高聚物聚乙烯吡咯烷酮(PVP-K30),可以在烧结温度600℃成功制备沉积在Pt/Ti/SiO_2/Si基片上多层结构的Pb(Zr_(0.52)Ti_(0.48))O_3-Ni_(0.5)Zn_(0.5)Fe_2O_4(PZT-NZFO)纳米复合薄膜。采用X-ray衍射仪测定纳米薄膜的相结构,扫描电镜与原子力显微镜观察纳米复合薄膜的表面形貌。相结构分析表明:铁电相与铁磁相共存在PZT-NZFO纳米复合薄膜中;微观形貌表明:表面微观形貌致密,无裂纹;此外,PZT-NZFO中PZT层与NZFO层相互交替,并且层与层之间的厚度可以得到较好地控制。PZT-NZFO纳米复合薄膜呈现明显的电滞回线与磁滞回线,进一步证明了PZT-NZFO复合纳米薄膜中同时存在着铁电相与铁磁相。介电性能显示:室温在1kHz,相对介电常数和介电损耗分别为165和0.02。磁性能结果显示:室温时,PZT-NZFO纳米复合薄膜的饱和磁化强度为2.6×10~4 A/m,内在矫顽力为1.19×10~4 A/m。加入高聚物后改进的溶胶-凝胶制备的PZT-NZFO复合纳米薄膜实验结果表明,这种致密的、无裂纹的、介电损耗低,并同时具有铁电与磁电的纳米复合薄膜在微型器件与集成电路中具有潜在的应用。

Polymer-assistant polyvinylpyrrolidone （PVP -K30 ） was introduced to the sol-gel processing route,and multilayered nanocomposite films of Pb（Zr 0. 52Ti（i.48 ） O3-（Ni（i. 5 Zn.. 5 ） Fe 2Oi（PZT-NZFO） were fabricated on Pt/Ti/SiO2 /Si substrates successfully by spin-coating at low firing temperatures 600℃.Structural characterization by X-ray diffraction and electron microscopy techniques reveals good surface and wel-controlled cross-sectional morphologies of these films. Coexistence of ferromagnetic and ferroelectric phases with obvious ferromagnetic and ferroelectric hysteresis loops are observed at room temperature. An appropriate dielectric constant with low loss tangent is obtained in low frequency exhibiting excellent die-lectric properties. The dielectric properties of nanocomposite thin film shows at 1kHz and room tempera-ture, the dielectric constant and loss tangent for the nanocomposite films are about 165 athe room-temperature magnetization values （ Ms ） is about 2. 6 X 104A/m, and the intrinsic coercivity （Hc ） is about 1. 1 9 × 10^4 A/m, respectively. The combination of high permeability and permittivity in the nanocomposite films presents potential applications in of the fields of microelectronic devices and inte-grated units.