首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
陈棋  尚学府  张鹏  徐鹏  王淼  今西誠之 《物理学报》2017,66(18):188201-188201
以溶胶凝胶法合成的高纯Li_(1.4)Al_(0.4)Ti_(1.6)(PO_4)_3(LATP)纳米晶体粉末为原料,通过流延法成膜,在950℃下煅烧5 h合成LATP固态电解质片;对其进行环氧树脂改性后,能量色散X射线光谱元素图像表明环氧树脂完全浸入LATP内部,可以有效防止水渗透.研究发现流延法合成的LATP固态电解质在25℃?C时电导率高达8.70×10~(-4)S·cm~(-1)、活化能为0.36 eV、相对密度为89.5%.经过环氧树脂改性后电导率仍高达3.35×10-4S·cm-1、活化能为0.34 e V、相对密度为93.0%.高电导隔水的环氧树脂改性LATP固态电解质可作为锂金属保护薄膜用于新型高比容量电池.  相似文献   

2.
The effects of varying the temperature and duration of the post-deposition anneal in watersaturated oxygen were investigated for YBa2Cu3O7−δ films of varying thickness. The films were produced by laser ablation from pressed powder targets consisting of BaF2,Y2O3, and CuO mixtures. This technique produces superconducting films with a highly textured surface. The films were fabricated on SrTiO3 substrates and were analyzed with X-ray diffraction, scanning electron microscopy, and temperature dependent resistivity. Critical current density (Jc) measurements were performed in magnetic fields up to 1 T. For film thickness on the order of 900 nm, completely c-axis oriented films were obtained with a 60 min anneal at 850°C. Thinner films required less annealing, either shorter times or lower temperatures, to achieve similar results, indicating that the optimal annealing conditions are dependent on film thickness.  相似文献   

3.
In2S3 layers have been grown by close-spaced evaporation of pre-synthesized In2S3 powder from its constituent elements. The layers were deposited on glass substrates at temperatures in the range, 200–350 °C. The effect of substrate temperature on composition, structure, morphology, electrical and optical properties of the as-grown indium sulfide films has been studied. The synthesized powder exhibited cubic structure with a grain size of 63.92 nm and S/In ratio of 1.01. The films grown at 200 °C were amorphous in nature while its crystallinity increased with the increase of substrate temperature to 300 °C. The films exhibited pure tetragonal β-In2S3 phase at the substrate temperature of 350 °C. The surface morphological analysis revealed that the films grown at 300 °C had an average roughness of 1.43 nm. These films showed a S/In ratio of 0.98 and a lower electrical resistivity of 1.28 × 103 Ω cm. The optical band gap was found to be direct and the layers grown at 300 °C showed a higher optical transmittance of 78% and an energy band gap of 2.49 eV.  相似文献   

4.
The comparative study of MgB2 film growth on Al2O3 and glass substrate by electrocrystallization technique is discussed. The precursor magnesium films were deposited by vacuum evaporation method. These magnesium films were then used as electrode for the growth of MgB2 films by electrocrystallization. The structural, morphological and superconducting properties of the electrocrystallized MgB2 films on Al2O3 substrate were examined by using XRD, SEM and electrical resistivity measurement techniques and compared with that of MgB2 films grown on glass substrate. The films deposited on Al2O3 substrates showed enhanced crystallinity and relatively higher Tc value compared to films deposited on glass substrates.  相似文献   

5.
郭昭龙  赵海新  赵卫 《物理学报》2016,65(6):64206-064206
以乙酸锌醇热法ZnO纳米粒子为基料, 通过溶胶-凝胶浸渍提拉法制备纳米ZnO-SiO2自清洁增透薄膜. 采用透射电镜, 光谱椭偏仪, 扫描电镜, X-射线衍射, 差热分析仪和UV-vis等技术对样品进行表征, 以亚甲基蓝的光催化降解为目标反应, 评价其光催化活性. 结果表明, ZnO纳米粒子为球粒状结构, 直径约12-20 nm, 特征紫外吸收波长位于375 nm 处; 与未涂覆纳米ZnO-SiO2自清洁增透薄膜的石英玻璃基底相比, 涂覆后石英玻璃在400-800 nm波长范围内平均透光率提升达4.17%, 具有良好的宽光谱增透行为; 且在紫外光激发下对亚甲基蓝染料具有光催化降解特性, 进而具备良好的自清洁性能.  相似文献   

6.
垂直磁各向异性稀土-铁-石榴石纳米薄膜在自旋电子学中具有重要应用前景.本文使用溅射方法在(111)取向掺杂钇钪的钆镓石榴石(Gd0.63Y2.37Sc2Ga3O12,GYSGG)单晶衬底上外延生长了2—100 nm厚的钬铁石榴石(Ho3Fe5O12,HoIG)薄膜,并进一步在HoIG上沉积了3 nm Pt薄膜.测量了室温下HoIG的磁各向异性和HoIG/Pt异质结构的自旋相关输运性质.结果显示,厚度薄至2 nm的HoIG薄膜(小于2个单胞层)在室温仍具有铁磁性,且由于外延应变,2—60 nm厚HoIG薄膜都具有很强的垂直磁各向异性,有效垂直各向异性场最大达350 mT;异质结构样品表现出非常可观的反常霍尔效应和“自旋霍尔/各向异性”磁电阻效应,前者在HoIG厚度小于4 nm时开始缓慢下降,而后者当HoIG厚度小于7 nm时急剧减小,说明相较于反常霍尔效应,磁电阻效应对HoIG的体磁性相对更加敏感;此外,自旋相关热电压随HoIG厚度减薄在整个厚度范围以指数方式下降,说明遵从热激化磁振子运动规律的自旋塞贝克效应是其主要贡献者.本文结果表明HoIG纳米薄膜具有可调控的垂直磁各向异性,厚度大于4 nm的HoIG/Pt异质结构具有高效的自旋界面交换作用,是自旋电子学应用发展的一个重要候选材料.  相似文献   

7.
The synthesis of combinatorial Bi2−xSbxSe3 thin films by arrested precipitation technique (APT) using triethanolamine-bismuth, triethanolamine-antimony and sodium selenosulphite as sources of Bi3+, Sb3+ and Se2−, respectively is investigated on commercial glass substrates. The growth mechanism of film formation, composition and surface morphology of the as deposited films were studied as a function of preparative parameters and bath composition. The films were monophasic, polycrystalline and covered the surface of the substrate completely. Energy dispersive X-ray analysis gave coherent elemental composition indicating single phase BiSbSe3 was made. The good results obtained for Bi2−xSbxSe3 thin films revealed that arrested precipitation technique is best suited for the deposition of large area thin films on conducting/nonconducting substrates to produce materials for device applications.  相似文献   

8.
The anisotropic magnetoresistance (AMR) in permalloy Ni81Fe19 film deposited on a 1.2 nm Co33Cr67 buffer layer was significantly enhanced. The high-resolution electron microscopy was used to study the microstructure of Ni81Fe19 film with and without Co33Cr67 buffer layer. It was found that Co33Cr67 buffer layer can induce good (1 1 1) texture, while without Co33Cr67 buffer layer, Ni81Fe19 film show randomly oriented grain structure. The Δρ/ρ enhancement is attributed to the decrease in the resistivity ρ of the Ni81Fe19 film due to the formation of the large (1 1 1) textured grains in Ni81Fe19 film with Co33Cr67 buffer layer. However, the surface roughness of substrate may limit the (1 1 1) textured grain size and induce additional grain boundaries in Ni81Fe19 film with Co33Cr67 buffer layer, limit the enhancement of the AMR effect.  相似文献   

9.
The crystal structure of YBa2Cu3O7−x thin films has been investigated by cross-section transmission electron microscopy. The samples were deposited on MgO (100) substrates at 670°C with substrate bias voltages of ±300 V. For the unbiased case, c-axis, a-axis and (103) oriented domains normal to the substrate surface were observed. In this film, the c-axis oriented domains are dominant, but the crystal often exhibits a longer c-lattice constant than that of the YBa2Cu3O7−x system, so extra cationic layers are inserted in the YBa2Cu3O7−x intrinsic stacking sequence. For the case of −300 V, rotated domains were dominant in the entire film; however, c-axis oriented domains also grow from the substrate surface. Small-angle semicoherent grain boundaries between them were observed. In the case of +300 V, all the grains show c-axis oriented YBa2Cu3O7−x. The degree of preferential orientation of the grains is reduced at negative bias voltage of −300 V and the structure defects are reduced by applying a positive bias of +300 V.  相似文献   

10.
刘志伟  路远  侯典心  邹崇文 《发光学报》2018,39(11):1604-1612
为了探究VO2薄膜受激光辐照的温度场分布,以及1 064 nm激光直接辐照100 s内至相变的激光功率密度阈值,并比较近红外和中红外波段透过率调制特性差异。首先基于COMSOL建立了薄膜受激光辐照的模型并进行了温度场仿真,然后分别测试了薄膜正反面被不同功率密度的1 064 nm激光辐照100 s内激光透过率随时间响应特性。实验中的VO2薄膜利用分子束外延法在Al2O3基底上制备得到。仿真结果表明,激光功率密度为25 W·mm-2时,50 nm厚薄膜在被辐照1 ms时间内即达到相变温度。经激光辐照实验发现:50 nm厚的VO2薄膜正反面受1 064 nm激光直接辐照100 s内至相变的功率密度阈值分别为4.1 W·mm-2和5.39 W·mm-2。30 nm厚VO2薄膜对1 064 nmn激光的透过率调制深度约为13%,对3 459 nm激光透过率调制深度约62%,说明VO2薄膜对近红外透过率调制特性不明显。  相似文献   

11.
The growth of SrMnO3 films on SrTiO3(111) substrates by pulsed laser deposition was studied and found to produce cubic and hexagonal (4H) structures in the SrMnO3 films. By adjusting the substrate temperature and oxygen pressure, the stability of the two phases was fine-tuned, resulting in the growth of cubic-SrMnO3(111) or 4H-SrMnO3(0001) film, with the 4H phase being the more stable at room temperature and ambient pressure in the bulk form. The growth temperature of the cubic phase was also further lowered relative to the bulk thermodynamics by strain at the heterointerface, and once obtained, it was stable at temperatures of up to 800 °C.  相似文献   

12.
The heteroepitaxy in DyMnO3/Er1Ba2Cu3O7-δ bilayer thin films on LaAlO3 (100) substates was characterized by four-circle X-ray diffractometry. The Er1Ba2Cu3O7-δ thin films on LaAlO3 (100) substrates were prepared by molecular-beam deposition (MBD) and post-growth annealing in wet and dry O2 at 880°C, whereas the DyMnO3 thin films on the Er1Ba2Cu3O7-δ/LaAlO3 (100) heterostructure were deposited by MBD and post-growth annealing in dry O2 at 750°C. The conventional X-ray diffraction (XRD) patterns as well as pole figures (φ-scans) for specific (hkl) reflections were acquired. The Er1Ba2Cu3O7-δ thin film in the DyMnO3/Er1Ba2Cu3O7-δ/LaAlO3 (100) heterostructure showed [001] oriented epitaxial growth, as expected. The DyMnO3 thin film on the Er1Ba2Cu3O7-δ epilayer in the heterostructure grew with (110) epitaxy in its metastable orthorhombic phase (lattice constants: ao=5.272 Å, bo=5.795 Å and co=7.38 Å). The heteroepitaxial relationships at the orthorhombic-DyMnO O3 (110) /Er1Ba2Cu3O7-δ (001) interface was determined as the following: DyMnO3 (110) Er1Ba2Cu3O7-δ (001), DyMnO3 [1 0] ¶r; Er1Ba2Cu3O7-δ[100] or Er1Ba2Cu3O7-δ[010], and DyMnO3 [001] ¶r; Er1Ba2Cu3O 7-δ[010] or Er1Ba2Cu3O7-δ [100].  相似文献   

13.
张彬  王伟丽  牛巧利  邹贤劭  董军  章勇 《物理学报》2014,63(6):68102-068102
采用电子束沉积方法,以钛酸锶(SrTiO3)为衬底制备铌(Nb)掺杂TiO2薄膜并研究后续H2气氛退火处理对其薄膜样品光电性能的影响.结果发现H2气氛热退火处理能有效改善Nb掺杂TiO2薄膜的导电率,最佳电阻率达到5.46×10-3Ω·cm,在可见光范围内的透光率为60%—80%.导电性能的改善与H2气氛退火处理后多晶薄膜的晶粒尺寸变大和大量的氧空位形成及H原子掺杂有关.  相似文献   

14.
采用直流磁控溅射和后退火工艺在掺氟的SnO2(FTO)导电玻璃衬底上制备VO2薄膜, 研究了不同退火时间和不同比例的氮氧气氛对VO2薄膜性能的影响, 对VO2薄膜的结晶取向、表面形貌、表面元素的相对含量和透过率随波长变化进行了测试分析, 结果表明在最佳工艺条件下制备得到了组分相对单一的VO2薄膜. 基于FTO/VO2/FTO结构在VO2薄膜两侧的透明导电膜上施加电压并达到阈值电压时, 观察到了明显的电流突变. 当接触面积为3 mm×3 mm时, 阈值电压为1.7 V, 阈值电压随接触面积的增大而增大. 与不加电压的情况相比, FTO/VO2/FTO结构在电压作用下高低温的红外透过率差值可达28%, 经反复施加电压, 该结构仍保持性能稳定, 具有较强的电致调控能力.  相似文献   

15.
Epitaxial thin films of Fe3O4 and CoFe2O4 on MgO (0 0 1) substrates were grown by molecular beam epitaxy at low temperature growth process. Magnetization and hysteresis loop of both films were measured to investigate magnetic anisotropic properties at various temperatures. Anomalous magnetic properties are found to be correlated with crystalline, shape, and stress anisotropies. The Fe3O4 film below Verwey structural transition has a change in crystal structure, thus causing many anomalous magnetic properties. Crystalline anisotropy and anomalous magnetic properties are affected substantially by Co ions. The saturation magnetization of Co–ferrite film becomes much lower than that of Fe3O4 film, being very different from the bulks. It indicates that the low temperature growth process could not provide enough energy to have the lowest energy state.  相似文献   

16.
采用直流磁控溅射和后退火氧化的方法在掺铝氧化锌(AZO)导电玻璃上制备了二氧化钒(VO2)薄膜,研究了不同的退火温度、退火时间对VO2/AZO复合薄膜制备的影响,并对复合薄膜的结构、组分、光电特性进行了测试与分析. 结果表明,导电玻璃上的AZO没有改变VO2的取向生长,但明显改变了VO2薄膜的表面形貌特征. 与用相同工艺和条件在普通玻璃基底上制备的VO2薄膜相比,VO2/AZO复合薄膜的相变温度降低约25 ℃,热滞回线宽度收窄至6 ℃,相变前后可见光透过率均在50%以上,1500 nm处红外透过率约为55%和21%,电阻率变化达3 个数量级. 该复合薄膜表面平滑致密,制备工艺简单,性能稳定,可应用于新型光电器件. 关键词: 2')" href="#">VO2 AZO 热致相变 光电特性  相似文献   

17.
18.
Ba0.65Sr0.35TiO3 (BST) thin films were deposited by RF sputtering with a very thin Ba0.65Sr0.35RuO3 (BSR) seeding-layer on Pt/Ti/SiO2/Si substrate. The crystallization of BST thin films and the surface morphology of BSR seeding-layer were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. XRD patterns show that the BSR seeding-layer affected the orientation of BST thin film, which is highly a-axis textured. It was also found that the BSR seeding-layer had a marked influence on the dielectric properties of BST thin films. Comparing with BST thin films directly deposited on Pt electrode, the dielectric relaxation can be suppressed and dielectric constant increased due to a possible reduction of interface oxygen vacancies at BST/BSR interface. Moreover, JV measurement indicates that the leakage current density of BST thin films on BSR seeding-layer were greatly reduced compared with that of BST thin films directly on Pt electrodes. The pyroelectric coefficient of BST thin films with BSR seeding-layer is 7.57 × 10−7 C cm−2 K−1 at 6 V/μm at room temperature (RT). Our results reveal that high pyroelectric property of BST thin film could be achievable using BSR seeding-layer as a special buffer.  相似文献   

19.
The thickness dependence of microstructures of La0.9Sr0.1MnO3 (LSMO) thin films grown on exact-cut and miscut SrTiO3 (STO) substrates, respectively, was investigated by high-angle X-ray diffraction (HXRD), X-ray small-angle reflection (XSAR), X-ray reciprocal space mapping and atomic force microscopy (AFM). Results show that the LSMO films are in pseudocubic structure and are highly epitaxial [0 0 1]-oriented growth on the (0 0 1) STO substrates. The crystalline quality of the LSMO film is improved with thickness. The epitaxial relationship between the LSMO films and the STO substrates is [0 0 1]LSMO[0 0 1]EXACT-STO, and the LSMO films have a slight mosaic structure along the qx direction for the samples grown on the exact-cut STO substrates. However, an oriented angle of about 0.24° exists between [0 0 1]LSMO and [0 0 1]MISCUT-STO, and the LSMO films have a mosaic structure along the qz direction for that grown on the miscut STO substrates. The mosaic structure of both groups of the samples tends to reduce with thickness. The diffraction intensity of the (0 0 4) peaks increases with thickness of the LSMO film. The XSAR and AFM observations show that for both groups, the interface is sharp and the surface is rather smooth. The mechanism was discussed briefly.  相似文献   

20.
Epitaxial thin films of YBa2Cu3O7 (YBCO) have been deposited on Y–ZrO2 (YSZ) substrates by means of the pulse laser deposition technique. It has been found that the initial epitaxy of YBCO thin films grown on YSZ can be significantly improved by using La1.85Sr0.15CuO4 (LSCO) as a buffer layer. X-ray diffraction measurements show that the epitaxial YBCO films have single in-plane orientation with YBCO [100]LSCO [100] and LSCO [100]YSZ [110]. The real-time resistance measurements reveal that with LSCO buffer layers the initial formation of the YBCO ultra-thin films changes from the island growth to the layer-by-layer growth.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号