共查询到18条相似文献,搜索用时 203 毫秒
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以醋酸锶、醋酸钡和钛酸四丁酯为前驱体原料,配制了不同浓度(0.05mol/L、0.1mol/L、0.3mol/L、0.4mol/L、0.5mol/L)的Ba0.65Sr0.35TiO3溶胶,采用溶胶-凝胶(Sol-Gel)和旋涂工艺,成功制备了BST薄膜.采用XRD、SEM和阻抗分析仪研究分析了前驱液浓度对BST薄膜的结晶、微观形貌和性能的影响.结果表明,在相同热处理温度下,随着前驱液浓度增加,薄膜的结晶程度、晶粒生长情况和介电常数依次提高,介电损耗降低.浓度为0.5mol/l的溶胶形成的薄膜的结晶程度较好;晶粒发育完善,晶粒与晶粒之间比较紧密,表面光滑致密无裂纹,颗粒尺寸约为60nm~80nm;且其介电性能最佳. 相似文献
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溶胶-凝胶法制备外延Ba1-xSrxTiO3薄膜及其结构与性能研究 总被引:5,自引:0,他引:5
应用溶胶-凝胶技术在Pt/MgO(100)衬底上成功地制备了Ba0.65Sr0.35TiO3外延薄膜.XRD和SEM分析结果表明该薄膜在O2气氛中650℃热处理1h后,其(001)面是沿着Pt(100)和MgO(100)面外延取向生长的;薄膜表面均匀致密,厚度为260nm,平均晶粒大小为48.5nm.当测试频率为10kHz时,BST薄膜的介电常数和损耗因子分别为480和0.02.介电常数-温度关系测试结果表明sol-gel工艺制备的Ba0.65Sr0.35TiO3薄膜其居里温度在35℃左右,且在该温度下Ba0.65Sr0.35TiO3薄膜存在扩散铁电相变特征.当外加偏置电压为3V时,BST薄膜的漏电流密度为1.5×10-7A/cm2.该薄膜可作为制备新型非制冷红外焦平面阵列和先进非制冷红外热像仪的优选材料. 相似文献
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钛酸锶钡薄膜的制备及其光学特性研究 总被引:2,自引:0,他引:2
用溶胶–凝胶法在石英和Al2O3单晶衬底上沉积Ba0.65Sr0.35TiO3薄膜,应用XRD与SEM表征了BST薄膜的晶化行为和表面形貌。在700℃退火1 h的薄膜,其表面光滑、晶粒大小分布均匀、无裂缝、无针孔。应用双光束光度计,在200~1000 nm的波长范围测量了薄膜的透射光谱,并根据“包络法”理论计算薄膜的折射指数。结果表明,当波长从近红外范围(1 000 nm)降低到可见光范围(430 nm)时,薄膜的折射率从2.16增加至2.35,当波长降低到紫外范围时,薄膜的折射率迅速增加,在365 nm处n =2.67。实验还发现沉积在Al2O3衬底上的BST的能隙约为3.48 eV。 相似文献
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用脉冲激光沉积工艺制备Ba0.5Sr0.5TiO3(简称BST)薄膜和Ba0.5Sr0.5TiO3/LaNiO3(简称BST/LNO)薄膜。在650℃原位退火10 min,获得了(100)和(110)择优取向生长的BST和BST/LNO薄膜,薄膜晶粒呈柱状结构,BST薄膜和BST/LNO异质结构薄膜的晶粒尺寸分别为150~200 nm和50~80 nm。在室温和1 MHz条件下,BST薄膜和BST/LNO异质结构薄膜的相对介电常数和介电调谐率分别达811和58.9%、986和60.1%;用LNO作底电极,可增益介电常数和介电调谐率。 相似文献
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采用溶胶-凝胶法,在302不锈钢表面制备了经不同温度热处理的ZrO2薄膜。通过原子力显微镜(AFM)、X射线衍射仪(XRD)和傅里叶变换红外光谱仪(FTIR),研究了热处理温度对ZrO2薄膜表面形貌和相结构的影响。研究结果表明:室温下ZrO2结构呈非晶态,随着温度升高,晶体结构逐渐由四方相(t-ZrO2)向单斜相(m-ZrO2)转变;当热处理温度从400℃升高到600℃时,薄膜表面ZrO2晶粒尺寸由40 nm逐渐增大到70.1 nm,表面粗糙度也由3.34 nm缓慢增大到5.3 nm;而当热处理温度为700℃时,ZrO2晶粒明显增大(109 nm),表面粗糙度迅速增大到33 nm;红外吸收谱显示,随着热处理温度的升高,非晶态ZrO2(648与460.9 cm-1)逐渐向480.2和574.7 cm-1处的t-ZrO2结构以及424.3和732.8 cm-1处的m-ZrO2结构转变,与XRD结果一致。 相似文献
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钙钛矿结构的钛酸锶钡(BST)薄膜作为优良的介电、铁电材料在新一代的微机械系统(MEMS)、动态存储器(DRAM)及其他器件上的广泛应用,使得BST薄膜的刻蚀特性越来越重要。该文利用反应离子刻蚀装置,研究了溶胶-凝胶工艺制备的钛酸锶钡薄膜在CHF3/Ar等离子气体中的刻蚀情况。通过分析刻蚀速率及薄膜刻蚀前后表面形貌的变化,结果表明,刻蚀过程是离子轰击、离子辅助化学反应和化学反应刻蚀共同作用的结果。刻蚀速率为5.1 nm/min。Sr元素较难去除,成为阻碍刻蚀的重要因素。 相似文献
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BST薄膜的Sol-Gel法制备及其电学性能的研究 总被引:3,自引:0,他引:3
应用溶胶-凝胶(Sol-Gel)工艺制备了组分为r(Ba:Sr)=0.65:0.35的BST薄膜,研究了BST薄膜的显微结构、介电特性和漏电流特性,实验结果表明:BST薄膜经650℃热处理后,巳形成完整的立方钙钛矿结构,薄膜经900℃热处理后,其表面光滑、致密、无裂纹、无针孔,圆球形的小颗粒均匀分布。当偏置电压为0时,BST薄膜的介电常数和损耗因子分别为542和0.035。漏电流特性分析结果表明:采用RuO2作为底电极,在1.5V的偏压下BST薄膜的漏电流密度为0.52μA/Cm^2,该值比Pt/RuO2混合底电极上制备的BST薄膜的漏电流密度(72nA/cm^2)大1个数量级,因此,Pt/RuO2混合底电极既克服了RuO2底电极漏电流大的缺点,又解决了Pt底电极难以刻蚀的困难,是制备大规模动态随机存取存储器的电容器列阵的最低底电极材料。 相似文献
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BST薄膜的磁增强反应离子刻蚀研究 总被引:1,自引:1,他引:0
分别以CF4/Ar和CF4/Ar/O2作为刻蚀气体,采用磁增强反应离子刻蚀(MERIE)技术对sol-gel法制备的BST薄膜进行刻蚀。结果表明,刻蚀速率与刻蚀气体的混合比率呈现非单调特性。当CF4/Ar的气体流量比R(CF4:Ar)为10:40时,刻蚀速率达到极大值。当CF4/Ar/O2的气体流量比R(CF4:Ar:O2)为9:36:5时,刻蚀速率达到最大值,最大刻蚀速率为8.47nm/min。原子力显微镜(AFM)分析表明,刻蚀后的薄膜表面粗糙度变大。对刻蚀后的薄膜再进行适当的热处理,可以去除部分残留物。 相似文献
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Structural and Electrical Characters of Ba0.6Sr0.4TiO3/La0.5Sr0.5CoO3 Thin Films by Plus Laser Deposition
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Epitaxial Ba0.6Sr0.4TiO3 (BST) thin films were deposited on LaAlO3 (LAO) substrates with the conductive metallic oxide La0.5Sr0.5CoO3 (LSCO) film as a bottom electrode by pulsed laser deposition (PLD). X-ray diffraction ~2 and Ф scan showed that the epitaxial relationship of BST/LSCO/LAO was [001] BST//[001] LSCO//[001] LAO. The atomic force microscope (AFM) revealed a smooth and crack-free surface of BST films on LSCO-coated LAO substrate with the average grain size of 120 nm and the RMS of 1.564 nm for BST films. Pt/BST/LSCO capacitor was fabricated to perform CapacitanceVoltage measurement indicating good insulating characteristics. For epitaxial BST film, the dielectric constant and dielectric loss were determined as 471 and 0.03, respectively. The tunabilty was 79.59% and the leakage current was 2.6310-7 A/cm2 under an applied filed of 200 kV/cm. Furthermore, it was found that epitaxial BST (60/40) films demonstrate well-behaved ferroelectric properties with the remnate polarization of 6.085 C/cm2 and the coercive field of 72 kV/cm. The different electric properties from bulk BST (60/40) materials with intrinsic paraelectric characteristic are attributed to the interface effects. 相似文献
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Ferroelectric Ba0.65Sr0.35TiO3 (BST) thin films on the Pt/Ti/SiO2/Si substrate have been successfully prepared by sol-gel. Such films have approximately 300 nm thicknesses with a remnant polarization of about 2.95 C/cm2 and a coercive field of about 21.5 kV/cm. The investigations of X-ray diffraction and atomic force microscopy show that the BST films annealed at 650 ℃ exhibit a tetragonal structure and that the films dominantly consist of large column or grains of about 89 nm in diameter. The curves of the temperature dependence of dielectric coefficient in different frequencies display the curie transition at the temperature around 23 ℃. The dielectric loss tangent of BST thin films at 100 kHz is less than 0.04. As a result, the BST thin films are more applicable for fabrication of infrared detector compared with the BST thin films reported previously. 相似文献
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Ferroelectric Ba0.65Sr0.35TiO3(BST) thin films on the Pt/Ti/SiO2/Si substrate have been successfully prepared by sol-gel. Such films have approximately 300 nm thicknesses with a remnant polarization of about 2.95 μC/cm2 and a coercive field of about 21.5 kV/cm. The investigations of X-ray diffraction and atomic force microscopy show that the BST films annealed at 650 °C exhibit a tetragonal structure and that the films dominantly consist of large column or grains of about 89 nm in diameter. The curves of the temperature dependence of dielectric coefficient in different frequencies display the curie transition at the temperature around 23 °C. The dielectric loss tangent of BST thin films at 100 kHz is less than 0.04. As a result,the BST thin films are more applicable for fabrication of infrared detector compared with the BST thin films reported previously. 相似文献
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Epitaxial Ba0.6Sr0.4TiO3 (BST) thin films were deposited on LaAlO3 (LAO) substrates with the conductive metallic oxide La0.5Sr0.5CoO3 (LSCO) film as a bottom electrode by pulsed laser deposition (PLD). Xray relationship of BST/LSCO/LAO was [001] BST//[001]LSCO//[001] LAO. The atomic force microscope (AFM)revealed a smooth and crackfree surface of BST films on LSCOcoated LAO substrate with the average grain size of 120 nm and the RMS of 1.564 nm for BST films.Pt/BST/LSCO capacitor was fabricated to perform CapacitanceVoltage measurement indicating good insulating characteristics. For epitaxial BST film, the dielectric constant and dielectric loss were determined as 471 and 0.03, respectively. The tunabilty was 79.59% and the leakage current was 2.63×107 A/crm2 under an applied filed of 200 kV/cm. Furthermore, it was found that epitaxial BST (60/40) films demonstrate wellbehaved ferroelectric properties with the remnate polarization of 6.085 μC/cm2 and the coercive field of 72 kV/cm. The different electric properties from bulk BST (60/40)materials with intrinsic paraelectric characteristic are attributed to the interface effects. 相似文献
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