New chemical methods for the deposition of Cu1·8S and TlSe thin film

New chemical methods for the deposition of thin film of Cu_1·8S and TlSe have been developed. The deposition of Cu_1·8S thin film has been performed by thiourea, ammonia and Cu²⁺ ions at room temperature, while TlSe thin films are obtained from triethanolamine as complexing agent, ammonia, sodium selenosulphate solution and Tl¹⁺ ions at room temperature. The electrical resistance, mobility, carrier concentration and optical band gap have been measured.     

氧化锆粉体的Rietveld方法X射线衍射定量相分析

对以不同温度和时间进行热处理的氧化锆粉体,利用X射线步长衍射数据及Rietveld修正方法进行了相含量的定量分析．结果表明,以500℃热处理2h的氧化锆粉体为立方和四方二相混合物（重量比为48：52）．在700℃热处理2h,立方相已消失,部分四方相也相变成单斜相,四方相与单斜相的重量比为35：65．800℃及900℃分别热处理8h及2h都得到接近纯单斜相的氧化锆粉体,四方相的含量分别为5wt％和1wt％．文中也讨论了热处理温度和时间对氧化锆粉体晶粒大小的影响．     

Cu2ZnSnS4纳米颗粒及其薄膜的制备与表征

采用热注入法,在油胺(OLA)中合成出Cu2ZnSnS4(CZTS)纳米颗粒,并在玻璃衬底上制备了薄膜,研究了不同合成温度对纳米颗粒生成的影响.通过X射线衍射仪、拉曼光谱仪、透射电子显微镜、扫描电子显微镜、紫外可见分光光度计对所得纳米晶材料的结构与成分、颗粒大小与形貌、光吸收谱进行了测试分析.研究结果表明:采用热注入法的最佳合成温度在260℃左右,该温度下生成的多晶CZTS纳米颗粒尺寸约10 nm,分散性良好,光学禁带宽度约1.5 eV.     

Formation of Cu2SnS3 thin film by the heat treatment of electrodeposited SnS–Cu layers

Thin films of copper tin sulfide (Cu₂SnS₃) were obtained by sulfurizing a stack of thin layers of Cu and SnS in nitrogen atmosphere. The film stack was obtained by the sequential electrodeposition of SnS and Cu. The Cu₂SnS₃ film was characterized for structural, morphological, composition, optical, spectroscopic, and electrical properties. The optimum condition for the formation of Cu₂SnS₃ was developed after testing different sulfurization temperatures. The films were polycrystalline with monoclinic structure which was confirmed by Raman and transmission electron microscopy analysis. The interplanar spacings estimated from the high resolution transmission electron microscopy images are 2.74, 2.19, and 2.06 Å. The average crystallite size is 13 nm, and the band gap of the film is in the range of 1 eV. The surface chemical composition determined by X-ray photoelectron spectroscopy showed the Cu:Sn:S ratio as 1.9:1:2.85 which is close to the stoichiometric Cu₂SnS₃. The films are p-type, photosensitive, and the conductivity measured in dark was in the range of 4 × 10^?3 Ω^?1 cm^?1. The comprehensive characterization presented in this paper will update the knowledge on this material.     

电子束蒸发法制备掺钇稳定氧化锆薄膜的光学特性研究

利用电子束蒸镀方法在单晶硅和石英玻璃上制备了掺不同Y_2O_3浓度的掺钇稳定ZrO_2薄膜(YSZ),用X射线衍射、原子力显微镜、扫描电子显微镜和透射光谱测定薄膜的结构、表面特性和光学性能,研究了退火对薄膜结构和光学性能的影响.结果表明:一定浓度的Y_2O_3掺杂可以使ZrO_2薄膜稳定在四方相,退火显著影响薄膜结构,随着温度的升高薄膜结构依次经历由非晶到四方相再到四方和单斜混合相转变;AFM分析显示薄膜表面YSZ颗粒随着退火温度的升高逐渐增大,表面粗糙度相应增大,晶粒大小计算表明,退火温度的提高有助于薄膜的结晶化,退火温度从400℃到1100℃变化范围内晶粒大小从15.6nm增大到46.3nm;同时利用纳秒激光对薄膜进行了破坏阈值测量,结果表明电子束蒸镀制备YSZ薄膜是一种制备高抗激光损伤镀层的有效方法.     

Synthesis and characterization of nanocrystallined zirconia by hydrothermal method

Nano-size zirconia was prepared by hydrothermal method using commercial zirconia powder. XRD study showed that the nano-size zirconia has an appreciable amount of monoclinic phase. The nano-size zirconia obtained has average particle size in the range of 24-36 nm. The SEM of nano-sized zirconia showed diminutively different morphology than the commercial one. TEM micrographs shows well-dispersed monoclinic ZrO₂ nanoparticles. The UV-DRS absorption spectrum of alkali treated zirconia showed an absorption peak at 235 nm (5.3 eV). The FTIR spectrum showed the purity of treated zirconia.     

Study of the properties of CuInSe2 materials prepared from nanoparticle powder

This work studies the properties of CuInSe₂ (CIS) thin films obtained from nanoparticle powder. The samples were prepared by direct thermal evaporation of ball milled powder from a tungsten crucible onto precleaned glass substrates, using a BALZERS coating unit. The as deposited films were annealed in a vacuum at different temperatures. The composition, structure, morphology and optical properties of these samples have been investigated. X-ray diffraction (XRD) results showed that the CuInSe₂ phase may be prepared by mechanical alloying method. The crystallites of the CIS powder were found to be partially copper-rich. The as-deposited film was polycrystalline in nature having chalcopyrite structure as a mainly phase. The surface morphology is homogeneous across the surface. Expected optical properties (E_g = 1.04 eV, α ≈ 10⁴ cm^? 1) and near stoichiometric composition (Cu: 23.62 at.%, In: 24.35 at.% and Se: 52.03 at.%) were determined.     

Rietveld refinement study of nanocrystalline copper doped zirconia

Structural studies of Cu-doped zirconia samples with varying Cu content have been carried out. Copper-zirconia samples containing 2-20 mol% Cu were prepared by the co-precipitation technique using tetramethylammonium hydroxide as the precipitating agent and calcined at 773 K in air. The powder XRD data following Rietveld refinement revealed stabilization of zirconia in both tetragonal and cubic phases for all the samples with some monoclinic impurity phase. A decrease in the unit cell parameters of the cubic and tetragonal phase indicates incorporation of copper in the zirconia lattice of both the phases. An increase in the copper concentration (up to 20 mol%) stabilizes zirconia into the cubic phase at the expense of the tetragonal phase, with a decrease in the crystallite size (6-8 nm). Rietveld refinement of the high temperature XRD data reveals that both cubic and tetragonal phases exist up to 723 K with the cubic phase dominating (80% at 723 K). At temperature higher than 723 K, cubic phase gets transformed into the tetragonal phase, which further transforms into the monoclinic phase at 1173 K. At 1173 K, copper comes out of the cubic zirconia lattice forming a separate copper oxide phase and only the tetragonal and monoclinic polymorphs of zirconia exist.     

Study of structural,optical and electrical parameters of ZnSe powder and thin films

Nanocrystalline ZnSe powder and thin film forms have been synthesized via chemical bath deposition technique. The ZnSe thin films are deposited onto ultrasonically clean glass substrates in an aqueous alkaline medium using sodium selenosulphate as Se^2? ion source. The ZnSe powder and thin film are characterized by structural, optical and electrical properties. It is confirmed from X-ray diffraction study that cubic phase is present in ZnSe thin film form with (111) as preferred orientation and hexagonal phase is present in ZnSe powder form with (100) as preferred orientation. Optical absorption measurement indicates the existence of direct allowed optical transition with a wide energy gap and blue shift in the fundamental edge has been observed in both cases. The optical band gap of ZnSe powder is greater than the thin film. The electrical conductivity (both dark and photoconductivity) measurements are also carried out in different temperature range and variation in activation energy has been calculated.     

真空蒸镀法制备Sb膜电极及其性能

采用真空蒸镀法制备了金属Sb膜电极, 通过XRD、SEM、恒流充放电循环、循环伏安(CV)等方法, 研究了Sb膜电极的结构、形貌和电化学性能, 并对嵌脱锂机理进行了分析. 结果表明: 蒸镀后, 金属Sb为六方晶体, (003)晶面择优取向. Sb膜电极与基底铜箔的微观形貌接近, Sb金属以片层颗粒堆积在Cu箔颗粒上面. 在首次嵌锂过程中, 能观察到Li₃Sb合金的生成和Sb相的消失, 在脱锂之后, 能观察到Sb相的重新出现和Li₃Sb合金的消失, 且Sb相还是回复到(003)面择优相. Sb膜电极的首次充放电比容量分别为652和454 mAh/g, 循环16周后放电比容量还为300 mAh/g, 性能远优于Sb粉电极.     

热障涂层用La2O3、Y2O3共掺杂ZrO2陶瓷粉末的制备及其相稳定性

采用反向化学共沉淀法制备了热障涂层用La₂O₃-Y₂O₃-ZrO₂（LaYSZ）原始复合粉末, 将原始粉末团聚造粒和热处理后得到适于等离子喷涂的团聚粉末. 采用电感耦合等离子体原子发射光谱（ICP-AES）、扫描电子显微镜（SEM）、霍尔流速计、X射线衍射（XRD）等方法分别对LaYSZ的化学组成、微观形貌、流动性和松装密度、高温相稳定性进行了研究. 结果表明: LaYSZ团聚粉末室温呈四方ZrO₂结构, 在1150℃热处理2h后为致密的球形或近球形颗粒, 粉末流动性较好, 适于等离子喷涂. LaYSZ团聚粉末在1300℃热处理100h后仍保持单一的四方ZrO₂晶型, 而8YSZ中有12mol%的四方相转变为单斜相; LaYSZ在1400℃热处理100h后, 单斜相含量为2mol%, 而8YSZ中单斜相含量达到47mol%, 表明La₂O₃、 Y₂O₃共掺杂稳定ZrO₂较单一Y₂O₃ 稳定ZrO₂具有更好的高温相稳定性.     

High spatially resolved morphological, structural and spectroscopical studies on copper oxide nanocrystals

Copper oxide nanocrystals decorated on multi-wall carbon nanotubes have been prepared. Comprehensive morphological, structural and spectroscopical studies have been carried out on the nanometre/atomic scale by the combination of high-resolution transmission electron microscopy and electron energy-loss near-edge structure in electron energy-loss spectroscopy, which has a high spatially resolved capacity advantage over the normally used analytical techniques such as x-ray powder diffraction (XRD) and x-ray photoelectron spectroscopy (XPS). The result reveals that highly crystalline cubic Cu(2)O nanocrystals with highly uniform dispersion, homogeneous size of about 5.3?nm and nearly spherical morphology are synthesized as the predominant phase, while rare individual monoclinic CuO nanocrystals with irregular shape are still present as the minor phase. The analysis based on the survey result and the structural symmetry difference between Cu(2)O and CuO demonstrates that XRD underestimates the presence of the CuO phase with much lower structural symmetry while XPS overestimates the proportion of CuO phase.     

N掺杂Cu2O薄膜的低温沉积及快速热退火研究

采用氧化亚铜(Cu_2O)陶瓷靶,利用射频磁控溅射沉积法在氮气和氩气的混合气氛下制备了N掺杂Cu_2O(Cu_2O∶N)薄膜,并在N_2气氛下对薄膜进行了快速热退火处理,研究了N_2流量和退火温度对Cu_2O∶N薄膜的生长行为、物相结构、表面形貌及光电性能的影响。结果显示,在衬底温度300℃、N_2流量12sccm条件下生长的薄膜为纯相Cu_2O薄膜;在N_2气氛下对预沉积薄膜进行快速热退火处理不影响薄膜的物相结构,薄膜的结晶质量随退火温度(450℃)的升高而显著改善;快速热退火处理能改善薄膜的结晶质量和缺陷,降低光生载流子的散射,增强载流子的传输,预沉积Cu_2O∶N薄膜经400℃退火处理后展示出较好的电性能,薄膜的霍尔迁移率(μ)为27.8cm~2·V~(-1)·s~(-1)、电阻率(ρ)为2.47×10~3Ω·cm。研究表明低温溅射沉积和快速热退火处理能有效改善Cu_2O∶N薄膜的光电性能。     

Zinc phthalocyanine — Influence of substrate temperature, film thickness, and kind of substrate on the morphology

Zinc phthalocyanine (ZnPc), C₃₂H₁₆N₈Zn, is a planar organic molecule having numerous optical and electrical applications in organic electronics. This work investigates the influence of various deposition parameters on the morphology of vapour thermal evaporated ZnPc films. For this purpose, ZnPc is deposited at different substrate temperatures up to 90 °C and film thickness up to 50 nm onto various substrates. The morphology of this ZnPc layers is characterised by X-ray diffraction (XRD), X-ray reflectivity (XRR) and atomic force microscopy (AFM) methods. XRD measurements show that all ZnPc films are crystalline in a triclinic (α-ZnPc) or monoclinic (γ-ZnPc) phase, independent from the kind of substrate, layer thickness, or substrate temperature. The ZnPc powder, the starting product for the thermally evaporated ZnPc films, is present in the stable monoclinic β-phase. Thus, the stacking of the ZnPc molecules changes completely during deposition. The crystallite size perpendicular to the substrate determined by XRD microstructure analysis is in the range of the layer thickness while the lateral size, obtained by AFM, is increasing with substrate temperature and film thickness. AFM and XRR show an increase of the layer roughness for thicker ZnPc layers and higher substrate temperatures during film deposition. The strain in the ZnPc films decreases for higher substrate temperatures due to enhanced thermal relaxation and for thicker ZnPc films due to lower surface tension.     

Structural and optical properties of Cu doped ZnO thin films by co-sputtering

This paper reports on the structural and optical properties of ZnCuO thin films that were prepared by co-sputtering for the application of p-type-channel transparent thin-film transistors (TFTs). Pure ceramic ZnO and metal Cu targets were prepared for the co-sputtering of the ZnCuO thin films. The effects of the Cu concentration on the structural, optical, and electrical properties of the ZnCuO films were investigated after their heat treatment. It was observed from the XRD measurements that the ZnCuO films with a Cu concentration of 7% had ZnO(002), Cu2O(111), and Cu2O(200) planes. The 7% Cu-doped ZnO films also showed a band-gap energy of approximately 2.05 eV, an average transmittance of approximately 62%, and a p-type carrier density of approximately 1.33 x 10(19) cm-3 at room temperature. The bottom-gated TFTs that were fabricated with the ZnCuO thin film as a p-type channel exhibited an on-off ratio of approximately 6. These results indicate the possibility of applying ZnCuO thin films with variable band-gap energies to ZnO-based optoelectronic devices.     

Growth of CZTS thin films by sulfurization of sputtered single-layered Cu–Zn–Sn metallic precursors from an alloy target

Cu₂ZnSnS₄ (CZTS) thin films were prepared by sulfurizing single-layered metallic Cu–Zn–Sn precursors which were deposited by DC magnetron sputtering using a Cu–Zn–Sn ternary alloy target. The composition, microstructure and properties of the CZTS thin films prepared under different sputtering pressure and DC power were investigated. The results showed that the sputtering rate of Cu atom increases as the sputtering pressure and DC power increased. The microstructure of CZTS thin films can be optimized by sputtering pressure and DC power. The CZTS thin film prepared under 1 Pa and 30 W showed a pure Kesterite phase and a dense micro-structure. The direct optical band gap of this CZTS thin film was calculated as 1.49 eV with a high optical absorption coefficient over 10⁴ cm^?1. The Hall measurement showed the film is a p-type semiconductor with a resistivity of 1.06 Ω cm, a carrier concentration of 7.904 × 10¹⁷ cm^?3 and a mobility of 7.47 cm² Vs^?1.     

Structural Modification of Al_(6)5Cu_(16.5)Ti_(18.5) Amorphous Powder through Annealing and Post Milling:Improving Thermal Stability

To improve thermal stability of the Al65Cu16.5Ti18.5 amorphous powder,structural modification of the amorphous powder was performed through annealing and post milling.Annealing above the crystallization temperature(Tx) not only induced nanoscale intermetallics to precipitate in the amorphous powder,but also increased Cu atomic percentage within the residual amorphous phase.Post milling induced the amorphization of the nanocrystal intermetallics and the formation of Cu9Al4 from the residual amorphous phase.Thus,a mixed structure consisting of amorphous phase and Cu9Al4 was obtained in the powder after annealing and post milling(the APMed powder).The phase constituent in the APMed powder did not change during the post annealing,which exhibited significantly improved thermal stability in comparison with the as-milled amorphous powder.     

Laser-Induced Phase Transitions in Vitreous Se Films Obtained by Vacuum-Thermal Evaporation

The results of the study of vitreous Se films obtained by a method of vacuum-thermal evaporation after their laser modification are presented. It is shown for the first time that a low-power laser irradiation of the film at a wavelength of 632.8 nm and room temperature results in a nucleation and growth of nanocrystallites of monoclinic and rhombohedral Se in an amorphous matrix of the film. The formation of the stable hexagonal Se phase is not observed. The appearance of nanocrystallites with an average size of ~20–30 nm is accompanied by a growth of a reflection coefficient of the film. The established new optical and structural properties of the formed films are stable in time at room temperature.     

利用Rietveld方法Y_2O_3稳定ZrO_2的定量相分析

利用多相混合物中某相的重量与它在Rietveld结构修正中求得的标度因子之间的关系，可以进行多相混合物的定量分析[1].本工作利用Rietveld修正和X射线步长扫描衍射数据对不同浓度Y2O3掺杂的ZrO2试样进行了相含量的定量分析，给出了各相含量的定量数据，同时还证实了由研磨引起四方相向单斜相转变的规律.     

YSZ thin films deposited by e-beam technique

YSZ thin films were grown evaporating cubic and tetragonal phase ZrO₂ stabilized by 8 wt.% of Y₂O₃ (8% of YSZ) ceramic powders by using e-beam deposition technique. Operating technical parameters that influence thin film properties were studied. The influence of substrate crystalline structure on growth of deposited YSZ thin film was analyzed there. The YSZ thin films (1.5-2 μm of thickness) were deposited on three different types of substrates: Al₂O₃, optical quartz (SiO₂), and Alloy 600 (Fe-Ni-Cr). The dependence of substrate temperature, electron gun power, and phase of ceramic powder on thin film structure and surface morphology was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The substrate temperature was changed in the range of 20-600° C (during the YSZ thin film deposition) and its influence on the crystallinity of deposited YSZ thin films was analyzed. It was found that electron gun power and substrate temperature has the influence on the crystallite size, and texture of YSZ thin films. Also, the substrate has no influence on the crystal orientation. The crystallite size varied between 20 and 40 nm and increased linearly changing the substrate temperature. The crystal phase of evaporated YSZ powder has the influence on the structure of the deposited YSZ thin films.