掺Nd纳米ZnO薄膜特性研究

研究了用真空蒸发法在玻璃衬底上制备稀土掺杂纳米ZnO薄膜结构、导电性及光透射性能。结果显示。在500℃氧化、热处理稀土元素Nd掺杂后能够明显改善纳米ZnO薄膜的结构特性，薄膜的晶粒尺寸随掺杂含量的增加而减小。掺Nd使ZnO薄膜的电性能有所改善但使纳米ZnO薄膜的光透射性有所降低。     

掺In纳米ZnO、CdS薄膜结构、光学特性分析

采用真空气相沉积法在玻璃衬底上制备纳米级ZnO和CdS薄膜.研究掺In和热处理对ZnO、CdS薄膜结构、光学特性的影响.实验给出,适当掺杂能够明显改善纳米ZnO、CdS薄膜的物相结构,ZnO薄膜的晶粒尺寸随掺杂含量的增加而减小,CdS薄膜晶粒尺寸随掺杂含量的增加而变大,但薄膜的光透射性有所降低.在短波范围内,ZnO薄膜的光透率好于CdS薄膜;在500 nm～1000 nm范围内,CdS薄膜的光透率好.掺In后ZnO薄膜的光学带宽从3.2eV减小至2.85 eV;掺In后CdS薄膜光学带宽从2.42 eV减小至2.35eV.     

RF溅射稀土掺杂ZnO薄膜的结构与发光特性

通过射频磁控溅射技术在Si(111)衬底上制备了未掺杂和La、Nd掺杂ZnO薄膜.XRD分析表明,ZnO薄膜具有c轴择优生长,La、Nd掺杂ZnO薄膜为纳米多晶薄膜.AFM观测,La、Nd掺杂ZnO薄膜表面形貌较为粗糙.从薄膜的室温光致光谱中看到,所有薄膜都出现了395 nm的强紫光峰和495 nm的弱绿光峰,La掺杂ZnO薄膜的峰强度增大,Nd掺杂ZnO薄膜的峰强度减弱,分析了掺杂引起PL峰强度变化的原因.     

RF溅射钕掺杂ZnO薄膜工艺与结构研究

通过射频磁控溅射技术在Si(111)衬底上制备了未掺杂和Nd掺杂ZnO薄膜,研究了衬底温度、氧分压以及Nd不同掺杂浓度等工艺参数对薄膜的影响.薄膜的结构和表面形貌通过XRD分析和AFM观测,表明制备的薄膜为ZnO:Nd纳米多晶薄膜,其表面形貌粗糙,不同沉积条件对薄膜生长有很大的影响.在纯氩气氛中、衬底温度为300℃的条件下,ZnO:Nd薄膜具有c轴择优取向.     

纳米ZnO薄膜制备及液态源掺杂

用真空蒸发法在玻璃和单晶硅片 (10 0 )上制备Zn薄膜 ,然后对Zn薄膜进行氧化、热处理获得纳米ZnO薄膜。对在硅片上制备的Zn薄膜一次性进行高温掺杂、氧化获得纳米ZnO∶P和ZnO∶B薄膜。研究不同氧化、掺杂温度和时间对薄膜结构、电学性能的影响。结果表明 :氧化温度和时间对ZnO薄膜结构影响较大 ,液态源掺P可明显改善纳米ZnO薄膜的导电性能、结构特性和化学组分     

Zn0.98Nd0.02O室温拉曼特性和伏安特性

通过固相反应工艺制备了Zn0.98Nd0.02O纳米颗粒,射频磁控溅射技术在Si(111)衬底上制备了Zn0.98Nd0.02O薄膜。应用XRD、AFM以及拉曼光谱等手段,分析了Zn0.98Nd0.02O纳米颗粒与薄膜的结构,并测试了Zn0.98Nd0.02O薄膜的室温伏安特性。表明Nd掺杂没有改变ZnO纤锌矿结构,Zn0.98Nd0.02O颗粒为纳米多晶粉末态,其薄膜为沿(100)、(101)方向生长的纳米多晶结构,表面形貌粗糙。拉曼光谱分析表明,Zn0.98Nd0.02O颗粒的局部应力增大,晶格畸变缺陷增加,缺陷态比较复杂,导致拉曼峰发生频移。Zn0.98Nd0.02O薄膜的室温I-V曲线表明了Zn0.98Nd0.02O薄膜的非线性导电特性。其非线性导电特性源于,薄膜中的载流子受外加电场在薄膜中所产生热激发进入导带导电,环境光中能量高于ZnO带隙的光子引起的光电导效应,以及薄膜中纳米粒子间的隧穿导电。在光辐照作用下,提高了薄膜内浅施主缺陷浓度,降低了薄膜的表面电阻率,增强了Zn0.98Nd0.02O薄膜的导电能力。     

玻璃衬底和Si衬底制备的Zn0.96Nd0.04O薄膜的结构研究

通过射频磁控溅射技术在玻璃衬底和Si（111）村底上制备了Zn0.96Nd0.04O薄膜。XRD分析表明,Zn0.96Nd0.04O薄膜是具有C轴择优生长的纳米多晶薄膜,Nd以替位原子的形式存在于ZnO晶格,Nd掺杂没有改变ZnO晶格结构。从AFM图中看出,薄膜表面形貌较为粗糙,Si衬底薄膜的晶粒具有规律且晶粒尺寸大于玻璃衬底。     

纳米ZnO薄膜制备及液态源掺杂

用真空蒸发法在玻璃和单晶硅片（100）上制备Zn薄膜，然后对Zn薄膜进行氧化、热处理获得纳米ZnO薄膜，对在硅片上制备的Zn薄膜一次性进行高温掺杂，氧化获得纳米ZnO:P和ZnO：B薄膜，研究不同氧化、掺杂温度和时间对薄膜的结构、电学性能的影响。结果表明：氧化温度和时间对ZnO薄膜结构影响较大，液态源掺P可明显改善纳米ZnO薄膜的导电性能、结构特性和化学组分。     

Mg-Al共掺杂ZnO薄膜的制备及其光学特性

采用溶胶-凝胶（sol—gel）旋涂法在载玻片上制备了不同A1掺杂量的Mg—Al共掺杂ZnO薄膜．在室温下利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和光致发光（PL）谱仪等手段分析了Mg—Al共掺杂Zn0薄膜的微结构、形貌和发光特性．XRD结果表明Mg．AI＆掺杂zn0薄膜具有六角纤锌矿结构;随着Al掺杂量的增加,共掺杂薄膜呈C轴取向生长．由SEM照片可知薄膜表面形貌随Al掺杂量的增加由颗粒状结构向纳米棒状结构转变．透射光谱表明共掺杂薄膜在可见光区内的透射率大于50％,紫外吸收边发生蓝移．在室温下的PL谱表明Mg—Al共掺杂zn0薄膜的紫外发射峰向短波长方向移动：Al掺杂摩尔分数为1％和3％的Mg—Al共掺杂ZnO薄膜的可见发射峰分别为596nm的黄光和565nm的绿光．黄光主要与氧间隙有关,而绿光主要与氧空位有关．     

稀土掺杂 ZnO 薄膜的研究进展

综述了近年来国内外稀土掺杂ZnO薄膜的研究现状,总结了稀土掺杂的方式及稀土掺杂对ZnO薄膜的结构、光、电、磁学性能以及抗腐蚀性能的影响,并介绍了稀土掺杂ZnO薄膜在气敏传感器方面的应用,最后探讨了稀土掺杂ZnO薄膜存在的问题及今后可能的研究方向.     

稀土Nd掺杂纳米SnO2薄膜特性

对采用真空气相沉积法在玻璃衬底上制备的稀土Nd掺杂的SnO2薄膜,进行结构、电学及光学特性的测试分析.实验表明:氧化、热处理条件为500 ℃、45 min时样品性能好.采用一步成膜工艺法制备的SnO2薄膜晶粒度较小,随掺Nd浓度的增大,从31.516 nm减小到25.927 nm;两步成膜工艺法制备的SnO2薄膜晶粒度随掺Nd浓度的增大,从45.692 nm增至66.256 nm.XRD分析,掺Nd(5 at%)薄膜沿[110]、[101]晶向的衍射峰加强,薄膜呈多晶结构.掺Nd可使薄膜透光率下降,而薄膜的薄层电阻随热处理温度升高和掺Nd浓度的增大,呈先降后升趋势.     

Fabrication and self-cleaning properties of reduced graphene oxide/TiO2:Nd nanohybrid thin films

Self-cleaning is an important technique for environmental purification. In this work, a series of reduced graphene oxide (rGO)-TiO₂:Nd nanohybrid films were deposited and characterized by various analysis techniques. The rGO incorporation and Nd doping obviously enhanced the self-cleaning properties including photocatalytic activity, photo-induced superhydrophilicity, and conductivity of the TiO₂ film. The effect of Nd content and rGO proportion on the self-cleaning properties was also studied. The efficient synergistic effect of rGO and Nd on the self-cleaning properties was observed and mainly ascribed to interface-induced effect. The measurement of band energy level and optical conductivity confirmed the interface-induced effect.     

Nonlinear optical investigations on Al doping ratio in ZnO thin film under pulsed Nd:YAG laser irradiation

In the present study, it has been reported on the effect of Al doping on linear and nonlinear optical properties of ZnO thin films synthesized by spray pyrolysis method. The structural properties of ZnO thin films with different Al doping levels (0–4 wt%) were analyzed using X-ray diffraction (XRD). The results obtained from XRD analysis indicated that the grain size decreased as the Al doping value increased. The UV–Vis diffused refraction spectroscopy was used for calculation of band gap. The optical band gap of Al-doped ZnO (AZO) thin films is increased from 3.26 to 3.31 eV with increasing the Al content from 0 to 4 wt%. The measurements of nonlinear optical properties of AZO thin films have been performed using a nanosecond Nd:YAG pulse laser at 532 nm by the Z-scan technique. The undoped ZnO thin film exhibits reverse saturation absorption (RSA) whereas the AZO thin films exhibit saturation absorption (SA) that shows RSA to SA process with adding Al to ZnO structure under laser irradiation. On the other hand, all the films showed a self-defocusing phenomenon because the photons of laser stay on below the absorption edge of the ZnO and AZO films. The third-order nonlinear optical susceptibility, χ⁽³⁾, of AZO thin films, was varied from of the order of 10^?5–10^?4 esu. The results suggest that AZO thin films may be promising candidates for nonlinear optical applications.     

Microstructure and hemocompatibility of neodymium doped zinc oxide thin films

By the radio frequency magnetron sputtering, both un-doped and neodymium (Nd) doped ZnO thin films were grown on Si (100) substrates. The microstructure of the films has preferred c-axis growth orientation confirmed by the X-ray diffraction spectra. The crystallite size of ZnO crystallite decreases with the increasing of Nd concentration. We show that the hemocompatibility can be improved by a suitable Nd doping in the ZnO thin films. It is verified by both calculations on surface energy and interfacial tension of the sample, and experiments on the wettability, the proteins adsorption, and the platelets adhesion.     

Lattice Effect on Magnetic and Electrical Properties of Ln2/3Pb1/3MnO3 （Ln=La,Pr, Nd） Films

Lattice effect on magnetic and electrical transport properties of Ln2/3Pb1/3MnO3 （Ln=La, Pr, Nd） films prepared by RF magnetron sputtering technique were investigated. With the decrease of the average ions radius 〈rA〉, the structure of Ln2/3Pb1/3MnO3 （Ln=La, Pr, Nd） targets transit from the rhombohedral phase to the orthorhombic phase, and the Curie temperature reduces rapidly with the decrease of 〈rA〉. The electrical properties show that films are the metallic state which can be fitted to the formula： ρ（T）=ρ0 ＋ ρ1T^2 ＋ ρ2T^4.5 at low temperatures. The temperature range of the ferromagnetic metallic state becomes narrow with the decrease of 〈rA〉. The phenomenon can be explained by the lattice effect.     

The effects of the doping elements on the optical properties of silver-based alloy layers for storage media usage

The effects of doping with copper and titanium on the optical properties of a silver alloy layer for storage media usage were investigated in this study. Doped silver alloy thin films were deposited using specially prepared targets and direct current (DC) sputtering. The results show that copper content ranging from 0.5 wt.% (AC0.5) to 1.5 wt.% (AC1.5) enhances the uniformity of thin film and reduces its grain size. For environmental stability, titanium was introduced, although this dopant will decrease the reflectivity of the silver-based alloy thin films. The silver alloy thin films with 1 wt.% titanium (ACT1) have good corrosion-resistant behavior. Films with 3 wt.% titanium (ACT3) are difficult to manufacture since the uniformity of the mechanical properties is poor and the grain size is coarser.     

Preparation of manganese-doped ZnO thin films and their characterization

In this study, pure and manganese-doped zinc oxide (Mn:ZnO) thin films were deposited on quartz substrate following successive ion layer adsorption and reaction (SILAR) technique. The film growth rate was found to increase linearly with number of dipping cycle. Characterization techniques of XRD, SEM with EDX and UV–visible spectra measurement were done to investigate the effect of Mn doping on the structural and optical properties of Mn:ZnO thin films. Structural characterization by X-ray diffraction reveals that polycrystalline nature of the films increases with increasing manganese incorporation. Particle size evaluated using X-ray line broadening analysis shows decreasing trend with increasing manganese impurification. The average particle size for pure ZnO is 29·71 nm and it reduces to 23·76 nm for 5% Mn-doped ZnO. The strong preferred c-axis orientation is lost due to manganese (Mn) doping. The degree of polycrystallinity increases and the average microstrain in the films decreases with increasing Mn incorporation. Incorporation of Mn was confirmed from elemental analysis using EDX. As the Mn doping concentration increases the optical bandgap of the films decreases for the range of Mn doping reported here. The value of fundamental absorption edge is 3·22 eV for pure ZnO and it decreases to 3·06 eV for 5% Mn:ZnO.     

Photoconductivity of chemically deposited rare-earth-doped CdS films

Highly photosensitive films with photocurrent to dark current ratios of the order of 10⁵ have been prepared by doping CdS with Nd and Pr. The conditions for preparing such films with different fluxes are described and results of excitation spectra, transmission spectra and rise-decay curves are presented. Values of trap depths are also calculated.     

Chemical,morphological, structural,optical, and magnetic properties of Zn<Subscript>1−x</Subscript>Nd<Subscript>x</Subscript>O nanoparticles

In the present investigation, we made an endeavor to fabricate the ZnO nanoparticles and achieved the tunable properties with Nd doping. The Nd-doped ZnO nanoparticles were characterized via X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) studies that confirmed the successful doping of Nd ions in the ZnO crystal lattice without amending its hexagonal phase. The particle morphology revealed nearly spherical particles with uniform size distribution. The band gap of these samples was determined using diffuse-reflectance spectra (DRS) and was found to vary from 3.17 to 3.21 eV with increasing Nd concentration. A broad and intense emission band at 1083 nm for Nd doped ZnO nanoparticles is observed and is assigned to corresponding emission transition ⁴F_3/2?→?⁴I_11/2 of Nd³⁺ ions. Furthermore, the magnetic studies indicate that the Nd doping altered the magnetic behavior of nanocrystalline ZnO particles from diamagnetic to ferromagnetic at 300 K and that the magnetization of these samples decreased with increasing Nd concentration. The tunable optical band gap as well as room-temperature ferromagnetism of these samples may find applications in both optoelectronics and spintronics.     

硼掺杂对金刚石薄膜生长特性的影响

采用HFCVD方法制备了掺硼金刚石薄膜,通过扫描电子显微镜和X射线衍射光谱对样品的表面形貌及结构进行了分析.结果表明,随着硼含量的增加,薄膜中晶粒的取向由(100)变为(111),然后趋向于无序化.硼的掺入同样影响到孪晶晶粒的形态及生长因子α,使得α变小.通过对样品的Raman光谱分析,得出在适当的硼掺杂浓度下,孪晶的出现使金刚石薄膜中的应力得到松弛,从而中心声子线Raman位移红移较小.