a-C:F薄膜的工艺及热稳定性研究

以CF4和CH4为源气体,用PECVD法制备了不同沉积条件下的a-C:F薄膜,测量了薄膜的厚度,研究了薄膜沉积速率和沉积工艺的关系,用傅立叶变换红外谱(FTIR)分析了薄膜的化学键结构,用扫描电镜和原子力显微镜分析了薄膜表面形貌,对薄膜在真空中进行了退火,研究了薄膜的热稳定性.实验表明,沉积速率在5～8 nm/min之间,薄膜表面平整、致密,在300℃内有较好的热稳定性.     

用锌靶反应性射频溅射氧化锌薄膜的特性

用锌靶反应性射频溅射制成了氧化锌薄膜.研究了不同的电阻率及沉积速率与溅射气氛中各种氧分压的关系.为了探索沉积薄膜的结晶性与沉积参数的关系,进行了透射电子衍射的研究.     

高性能导电薄膜的制备

采用磁控溅射法在玻璃基底上制备了Cr-Cu-Al-Cr薄膜,用焊接法测试薄膜附着性能,用X射线衍射仪、原子力显微镜和台阶仪对薄膜进行表征,研究溅射过程中以及在高温大气环境下薄膜的防氧化方法,分析薄膜晶粒大小与电性能关系,制备出性能较好的导电膜。     

Ti-Al共掺ZnO薄膜的应力、结构和光电性能研究

利用直流磁控溅射工艺,在水冷玻璃衬底上成功沉积出了高透光、低电阻率的Ti-Al共掺ZnO(TAZO)透明导电薄膜.X射线衍射(XRD)研究结果表明,TAZO薄膜为具有c轴择优取向的六角纤锌矿结构多品薄膜.研究了TAZO薄膜的应力、结构以及光电性能与薄膜厚度的关系,结果表明.当薄膜厚为531 nm时,薄膜晶格畸变最小,具...     

溶胶—凝胶法制备PZT薄膜的结构和波导特性

采用溶胶－凝胶方法制备了ＰＺＴ（５０／５０）薄膜，用椭偏仪和透射光谱分别测量并计算了年鉴备在Ｓｉ（１１１）、石英玻璃基片上薄膜的折射率、研究了薄膜的相结构与折射率之间的关系以及折射率和消光系数的色散关系。用棱镜耦合的方法测量了薄膜的波导损耗，并给出了波导损耗与工艺过程的关系。     

准分子脉冲激光沉积法制备的ZrO2薄膜结构和电学性能的研究

采用准分子脉冲激光沉积法 (PLD)分别在Pt/Ti/SiO2 /Si和SiO2 /Si衬底上制备了ZrO2 薄膜 ,采用扩展电阻法 (SRP)研究了薄膜纵向电阻分布 ;采用X射线衍射法 (XRD)研究了衬底温度对ZrO2 薄膜结晶性能的影响 ;精确测试了薄膜的表面粗糙度 ;讨论了薄膜结晶性能与其电学I V特性之间的关系。     

锆钛酸铅铁电薄膜的制备及光伏特性研究进展

介绍了铁电材料光伏效应的研究背景,指出了锆钛酸铅铁电薄膜光伏特性的研究意义。分析、归纳了锆钛酸铅铁电薄膜电极、膜厚和退火制度(退火温度、退火时间和退火气氛)等工艺参数与所制样品的界面层厚度、肖特基势垒以及取向的关系,综述了这些工艺参数对锆钛酸铅铁电薄膜光伏特性影响的研究现状,提出了锆钛酸铅铁电薄膜光伏特性研究中亟待解决的问题。     

衬底温度对超声喷雾法制备大面积绒面SnO_2:F薄膜特性影响的研究

详细研究了衬底温度对超声喷雾热分解工艺制备的大面积绒面SnO2:F薄膜的影响和薄膜微结构与薄膜电学、光学性能之间的关系。试验曲线和SEM图的研究结果表明,将衬底温度从370℃提高到470℃以上薄膜结晶程度大大提高,晶粒尺寸明显增大;温度在470℃左右绒度达到13%。文章同时对超声喷雾热分解工艺制备大面积绒面SnO2:F薄膜做了工艺探索,并将实验制得的薄膜用于制备非晶硅薄膜电池,其效率达到了6.46%。     

CdS薄膜的制备、结构和光致发光性能

CdS薄膜是一种n型半导体材料,用于CdTe多晶薄膜太阳电池的窗口层,其质量直接影响太阳电池的光电转换效率和寿命。用磁控溅射法制备了CdS薄膜,通过对薄膜进行X射线衍射(XRD)、扫描电子显微镜(SEM)、光致发光和紫外-可见光谱等测试,研究了CdS薄膜的制备工艺对薄膜结晶度、表面形貌和禁带宽度的影响关系。研究发现,随着CdS薄膜溅射功率的升高,薄膜的结晶度变好,晶粒增大,薄膜增厚,光致发光峰强度增加,禁带宽度减小;随着溅射气压减小,薄膜厚度增大,光致发光峰强度减小,禁带宽度减小。     

有机材料衬底ITO透明导电膜的结构和导电特性研究

采用真空反应蒸发技术，蒸发高纯度铟锡合金，在有机薄膜基片上制备出高质量的ＩＴＯ透明导电薄膜．研究了薄膜结构及电阻率、载流子浓度和迁移率等电学参数对制备条件的依赖关系．对制备薄膜的导电机制进行了研究     

ZnO/Ag/ZnO多层膜的制备和性质研究

采用射频磁控溅射ZnO陶瓷靶和直流磁控溅射Ag靶的方法制备了ZnO/Ag/ZnO多层膜。用X射线衍射仪、紫外–可见分光光度计、四探针测试仪和金相显微镜对ZnO/Ag/ZnO薄膜的结构、光学透过率、方阻和稳定性进行了研究。结果表明,ZnO(60nm)/Ag/(10nm)/ZnO(60nm)薄膜呈现多晶结构,薄膜在520nm处的光学透过率高达87.5%,方阻Rs为6.2Ω/□。随着顶层ZnO薄膜厚度的增加,ZnO/Ag/ZnO薄膜的稳定性提高。     

Catalyst-free growth of ZnO nanowires on various-oriented sapphire substrates by pulsed-laser deposition

Catalyst-free growth of one-dimensional zinc oxide (ZnO) nanowires is reported. ZnO nanowires were synthesized on ZnO buffer layers deposited on various-oriented sapphire substrates. Syntheses of ZnO buffer layers and nanowires were performed by ultraviolet pulsed-laser deposition. ZnO nanowire's number density was the lowest in the case of using m-cut sapphire substrates. ZnO nanowires grown on a-cut sapphire substrates had vertical alignment with distances of tens to hundreds of nanometers. On the other hand, ZnO nanowires grown on c-cut sapphire substrates had the biggest nucleation rate. The dependence of crystalline orientation of ZnO buffer layers on the orientation of sapphire substrates were investigated by electron back scatter diffraction measurement. From their results, the growth models of ZnO buffer layers were suggested and the variations in morphological properties of ZnO nanowires were discussed.     

ZnO纳米棒与Si(111)和Si(100)衬底的外延关系(英文)

运用热蒸发技术在Si(111)和Si(100)基片上制备了ZnO纳米棒。SEM表征显示,ZnO纳米棒的直径约100nm,长度均匀,大约3μm;XRD表征发现ZnO纳米棒沿[0001]晶向择优生长。通过实验结果与理论分析得出:对于Si(111)基片上的样品,大部分ZnO纳米棒沿6个对称方向生长,而且与基片之间的夹角为54.7°,ZnO与Si(111)的外延关系为[0001]ZnO‖[114]Si,[0001]ZnO‖[4]Si,[0001]ZnO‖[141]Si,[0001]ZnO‖[4]Si,[0001]ZnO‖[411]Si,或[0001]ZnO‖[4]Si。对于Si(100)基片上的样品,大部分ZnO纳米棒沿4个对称方向生长,与基片之间的夹角为70.5°,其外延关系为[0001]ZnO‖[114]Si,[0001]ZnO‖[4]Si,[0001]ZnO‖[14]Si,或[0001]ZnO‖[14]Si。通过比较分析得出Si基片可以控制ZnO纳米棒的生长方向。     

Al薄膜对(002)ZnO/Al/Si结构基片中ZnO薄膜特性影响的实验研究

采用射频磁控溅射法沉积制备了(002)ZnO/A l/Si复合结构。研究了Al薄膜对(002) ZnO/Al/Si复合结构的声表面波器件(SAWD)基片性能影响以及当ZnO 薄膜厚度一定时的Al膜最佳厚度。采用X射线衍射(XRD)对Al和ZnO薄膜进行了结构表征 ,采用 扫描电镜(SEM)对ZnO薄膜进行表面形貌表征,并从薄膜生长机理角度进行了分析。结果 表明,加Al薄膜有利于ZnO薄膜按(002)择优取向生长,并且ZnO 薄膜的结晶性能提高;与(002)ZnO/Si结构基片相比,当Al薄膜 厚为100nm时,(002)ZnO/Al/Si结构中ZnO薄 膜的机电耦合系数提高 了65%。     

Synthesis and photoluminescent properties of ZnO:Cu/ZnO core/shell nanocrystals

ZnO:Cu/ZnO core/shell nanocrystals are synthesized by a two-step solution-phase process. The morphology, structure and optical properties of the samples are detected by scanning electron microscopy, Raman, absorption and luminescence spectroscopy. The increase of particle size confirms the growth of ZnO shell. The segregation of CuO phase observed in ZnO: Cu core is not detected in ZnO:Cu/ZnO core/shell nanocrystals from Raman spectra. It is suggested that some Cu ions can be segregated from ZnO nanocrystals, and the separated Cu ions can be incorporated inside ZnO shell after the growth of ZnO shell. The visible emission mechanism is discussed in detail, and the photoluminescence analysis indicates that the core/shell structure helps to eliminate the surface-related emission.     

Sol-gel-derived ZnO/Cu/ZnO multilayer thin films and their optical and electrical properties

Sol-gel preparation of transparent conducting ZnO/Cu/ZnO multilayer thin films has been investigated. CuO thin films were deposited on glass substrates via a dip-coating method. The CuO thin films were further subjected to reductive annealing in hydrogen to form highly conductive Cu thin films with sheet resistances as low as 10 Ω/□. ZnO/Cu/ZnO multilayers were successfully prepared in a similar way by reducing ZnO/CuO/ZnO. The sheet resistance of the ZnO/Cu/ZnO multilayer thin films is about 10 kΩ/□, which is much higher than that of the pure Cu thin films. The formation of large discrete Cu crystallites in the multilayers explains the poor electrical conductivity of the sol-gel-derived ZnO/Cu/ZnO multilayers.     

Inside Front Cover: Polyvinylpyrrolidone‐Directed Crystallization of ZnO with Tunable Morphology and Bandgap (Adv. Funct. Mater. 18/2007)

A biomimetic approach for the shape‐selective synthesis of ZnO particles with controlled band gaps and morphologies at low temperatures is reported by Jianhui Zhang and co‐workers on p. 3897. Shape‐selective synthesis of ZnO is achieved by selective passivation of specific ZnO facets. Up to fifteen types of high‐purity ZnO structures were produced in this manner, allowing adjustment of room‐temperature photoluminescence and band gap. A novel polyvinylpyrrolidone (PVP)‐directed crystallization route is successfully developed for the shape‐selective synthesis of ZnO particles with distinctive shapes, including monolayer, bilayer, and multilayer structures, gears, capped pots, hemispheres, and bowls, at temperatures as low as 32 °C. This route is based on exploiting a new water/PVP/n‐pentanol system. In the system, PVP can greatly promote ZnO nucleation by binding water and direct ZnO growth by selectively capping the specific ZnO facets, which is confirmed by IR absorption spectra. The bandgap of the ZnO particles is readily tuned by modifying the product morphology by adjusting the PVP chain length, PVP amount, water volume, and reaction temperature. The remarkable ZnO structures and the biomimetic method demonstrated here not only expand the structures and applications of ZnO but also provide a new approach to explore the unusual structures for novel physicochemical properties and technological applications. Furthermore, the novel ZnO/Au/ZnO sandwich structure is successfully fabricated by inserting a Au plate into the bilayer ZnO structure.     

Co‐synthesis of ZnO–CuO Nanostructures by Directly Heating Brass in Air

ZnO–CuO nanostructures have been simultaneously synthesized by directly heating a CuZn alloy (brass) on a hotplate in ambient conditions. Depending on the Zn concentrations in the brasses, the dominant products transition from CuO nanowires to ZnO nanostructures. By changing the growth temperature and local Zn contents, 1D ZnO nanowires/nanoflakes, 2D ZnO nanosheets, and complicated 3D ZnO networks are obtained. Electron microscopy studies show that the as‐synthesized ZnO nanoflakes and nanosheets are single crystalline. Based on “self‐catalytic” growth, a tip‐growth mechanism for ZnO nanostructures is discussed, in which the Cu in brass plays an important role to confine the lateral growth of ZnO. Finally, the electron field emission from the ZnO–CuO hybrid systems is tested for the demonstration of potential applications.     

Atomic layer deposition of ZnO on graphene for thin film transistor

A ZnO/graphene composite thin film was obtained by depositing ZnO on graphene through an Atomic Layer Deposition (ALD) process. The graphene layer was synthesized through a Chemical Vapor Deposition (CVD) process. The achievement of ZnO deposition on graphene was attributed to the Perylene Tetracarboxylic Acid (PTCA) treatment on graphene. Both ZnO Thin Film Transistor (TFT) and ZnO/graphene TFT were fabricated and tested. The results show that both of them displayed a high ON/OFF ratio, while ZnO/graphene TFT displayed an enhanced carrier mobility over ZnO TFT.     

Tailoring the Optical Properties of Epitaxially Grown Biaxial ZnO/Ge,and Coaxial ZnO/Ge/ZnO and Ge/ZnO/Ge Heterostructures

Heterostructures of epitaxially grown biaxial ZnO/Ge, and coaxial ZnO/Ge/ZnO and Ge/ZnO/Ge heterostructured nanowires with ideal epitaxial interfaces between the semiconductor ZnO sublayer and the Ge sublayer have been fabricated via a two‐stage chemical vapor–solid process. Structural characterization by high‐resolution transmission electron microscopy and electron diffraction indicates that both the ZnO and Ge sublayers in the heterostructures are single crystalline. A good epitaxial relationship of (100)_ZnO∥(2 0)_Ge exists at the interface between ZnO and Ge in the ZnO/Ge biaxial heterostructure. There is also an epitaxial relationship of (0 0)_ZnO∥(020)_Ge at the interface between the ZnO and Ge substructures in the coaxial ZnO/Ge/ZnO heterostructures, and a good epitaxial relationship of (0 0)_ZnO∥(0 0)_Ge at the interface between ZnO and Ge in the Ge/ZnO/Ge coaxial heterostructure. Structural models for the crystallographic relationship between the wurtzite‐ZnO and diamond‐like cubic‐Ge subcomponents in the heterostructures are given. The optical properties for the synthesized heterostructures are studied by spatially resolved cathodoluminescence spectra at low temperature (20 K). Excitingly, the unique biaxial and coaxial heterostructures display unique new luminescence properties. It is concluded that the ideal epitaxial interface between ZnO and Ge in the prepared heterostructures induces new optical properties. The group II–VI Ge‐based nanometer‐scale heterostructures and their interesting optical properties may inspire great interest in exploring related epitaxial heterostructures and their potential applications in lasers, gas sensors, solar energy conversion, and nanodevices in the future.