Synthesis of CuS thin films by microwave assisted chemical bath deposition

In this study, oriented CuS nanoplates standing perpendicularly on F: SnO₂ (FTO) coated glass substrates have been prepared through a mild microwave assisted chemical bath deposition process in which copper acetate reacted with ethylenediamine tetraacetate acid disodium and thioacetamide in aqueous solution within 40 min. The effects of reaction time and microwave radiation on the treatment process were investigated. The morphology, structure, and composition of the yielded nanostructures have been confirmed by X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), and scanning electron microscope (SEM). Also, the correlation between the reflectance, transmittance coefficient in the UV and the thickness of films was established. Furthermore, a two-point probe was used for resistivity measurements. We believe this simple chemical conversion technique can be further extended to the synthesis of other semiconductors with various morphologies.     

电子束、离子辅助和离子束溅射三种工艺对光学薄膜性能的影响

运用电子束、离子辅助和离子束溅射三种镀膜工艺分别制备光学薄膜,包括单层氧化物薄膜和增透膜,然后采取一系列测试手段,如Zygo轮廓仪、原子力显微镜、表面热透镜技术和X射线衍射等技术,来分析和研究不同的工艺对这些薄膜性能的不同影响,以判断合理的沉积工艺。     

Effect of freon flow rate on tin oxide thin films deposited by chemical vapor deposition

High quality fluorine-doped tin oxide (SnO₂:F) films on glass substrates were been prepared using chemical vapor deposition (CVD) method. The electrical properties, surface morphologies, structural properties and optical properties of the films were studied by varying the freon flow rates. The structure was analyzed by X-ray diffraction (XRD). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to study the morphology. Energy-dispersive spectroscopy (EDS) was conducted to understand the surface fluorine composition of the film. The results showed that crystalline structure of the film had a have cassiterite-like diffraction patterns with a preferred orientation of (1 1 0). Surface roughness was evaluated by atomic force microscopy, characterized by root mean square (RMS) and average value (Ra). The SnO₂:F resistivity decreased as the freon flow rate increased. The films had a uniform thickness and a transmittance of 80–90% within the visible region of the spectrum.     

Ta_2O_5薄膜的低能离子辅助蒸镀

用低能氧离子辅助蒸镀技术,制备了一系列Ta_2O_5薄膜.观测了薄膜的微结构,测量了薄膜的光吸收和光散射.实验指出,离子束轰击和基片加热同时进行,能够制得透明而匀均的Ta_2O_5薄膜.     

Laser deposition of cryoglobulin blood proteins thin films by matrix assisted pulsed laser evaporation

We report the first successful deposition of type II cryoglobulin blood protein thin films by matrix assisted pulsed laser evaporation (MAPLE) using a KrF^* excimer laser source (λ = 248 nm, τ_FWHM ≈ 20 ns) operated at a repetition rate of 10 Hz. We demonstrate by AFM and FTIR that MAPLE-deposited thin films consist of starting type II cryoglobulin only, maintaining its chemical structure and biological functionality, being properly collected and processed. The dependence on incident laser fluence of the induced surface morphology is presented. The presence of type II cryoglobulin was revealed as aggregates of globular material in the MAPLE-deposited thin films and confirmed by standard cryoglobulin tests.     

Study of the structure and electrical properties of the copper nitride thin films deposited by pulsed laser deposition

Copper nitride thin films were prepared on glass and silicon substrates by ablating a copper target at different pressure of nitrogen. The films were characterized in situ by X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and ex situ by X-ray diffraction (XRD). The nitrogen content in the samples, x = [N]/[Cu], changed between 0 and 0.33 for a corresponding variation in nitrogen pressure of 9 × 10⁻² to 1.3 × 10⁻¹ Torr. Using this methodology, it is possible to achieve sub-, over- and stoichiometric films by controlling the nitrogen pressure. The XPS results show that is possible to obtain copper nitride with x = 0.33 (Cu₃N) and x = 0.25 (Cu₄N) when the nitrogen pressure is 1.3 × 10⁻¹ and 5 × 10⁻² Torr, respectively. The lattice constants obtained from XRD results for copper nitride with x = 0.25 is of 3.850 Å and with x = 0.33 have values between 3.810 and 3.830 Å. The electrical properties of the films were studied as a function of the lattice constant. These results show that the electrical resistivity increases when the lattice parameter is decreasing. The electrical resistivity of copper nitride with x = 0.25 was smaller than samples with x = 0.33.     

Nanomechanical characteristics of SnO2:F thin films deposited by chemical vapor deposition

The nanoindentation characterizations and mechanical properties of fluorine-doped tin oxide (SnO₂:F) films deposited on glass substrates, using chemical vapor deposition (CVD) method, were studied, which included the effects of the indentation loads, the loading time and the hold time on the thin film. The surface roughness, fractal dimension and frictional coefficient were also studied by varying the freon flow rates. X-ray diffraction (XRD), atomic force microscopy (AFM) and frictional force microscopy (FFM) were used to analyze the morphology of the microstructure. The results showed that crystalline structure of the film had a high intensity (1 1 0) peak orientation, especially at a low freon flow rate. According to the nanoindentation records, the Young's modulus ranged from 62.4 to 75.1 GPa and the hardness ranged from 5.1 to 9.9 GPa at a freon flow rate of 8000 sccm. The changes in measured properties were due to changing loading rate.     

利用等离子体辅助脉冲磁控溅射实现 多晶硅薄膜的低温沉积

本文报道了利用电感耦合等离子体辅助中频直流脉冲磁控溅射在温度300 ℃ 以下沉积氢化多晶硅薄膜的制备方法. 利用拉曼散射、X射线衍射、透射电子衍射和傅里叶红外光谱对多晶硅薄膜进行了表征. 详细研究了氢气在沉积过程中所起的作用, 并结合Langmuir探针和发射光谱等等离子体诊断方法, 对辅助等离子体源在多晶硅薄膜制备过程中所起到的作用进行了讨论.     

离子束辅助沉积硅薄膜负极材料的研究

采用离子束辅助沉积法制备了锂离子电池硅薄膜负极材料,研究了硅薄膜的晶体结构、表面形貌和电化学性能.研究结果表明：硅薄膜是非晶态的结构;非晶态硅薄膜发生嵌脱锂反应的电位分别为0.03 V与0.34 V和0.16 V与0.49 V;硅薄膜表现出很高比容量和充放电效率,其可逆比容量和库仑效率分别为3134.4 mAh/g和87.1％;硅薄膜具有优异的循环性能,在0.5C倍率下200次循环后容量保持率为92.2%. 关键词： 硅薄膜 离子束辅助沉积 锂离子电池 负极材料     

电子束、离子辅助和离子束溅射三种工艺对光学薄膜性能的影响

 运用电子束、离子辅助和离子束溅射三种镀膜工艺分别制备光学薄膜，包括单层氧化物薄膜和增透膜，然后采取一系列测试手段，如Zygo轮廓仪、原子力显微镜、表面热透镜技术和X射线衍射等技术，来分析和研究不同的工艺对这些薄膜性能的不同影响，以判断合理的沉积工艺。     

Morphological and optical properties of silicon thin films by PLD

Silicon thin films have been prepared on sapphire substrates by pulsed laser deposition (PLD) technique. The films were deposited in vacuum from a silicon target at a base pressure of 10⁻⁶ mbar in the temperature range from 400 to 800 °C. A Q-switched Nd:YAG laser (1064 nm, 5 ns duration, 10 Hz) at a constant energy density of 2 J × cm⁻² has been used. The influence of the substrate temperature on the structural, morphological and optical properties of the Si thin films was investigated.Spectral ellipsometry and atomic force microscopy (AFM) were used to study the thickness and the surface roughness of the deposited films. Surface roughness values measured by AFM and ellipsometry show the same tendency of increasing roughness with increased deposition temperature.     

Characterization of polymer thin films obtained by pulsed laser deposition

The development of laser techniques for the deposition of polymer and biomaterial thin films on solid surfaces in a controlled manner has attracted great attention during the last few years. Here we report the deposition of thin polymer films, namely Polyepichlorhydrin by pulsed laser deposition. Polyepichlorhydrin polymer was deposited on flat substrate (i.e. silicon) using an NdYAG laser (266 nm, 5 ns pulse duration and 10 Hz repetition rate).The obtained thin films have been characterized by atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and spectroscopic ellipsometry.It was found that for laser fluences up to 1.5 J/cm² the chemical structure of the deposited polyepichlorhydrin polymer thin layers resembles to the native polymer, whilst by increasing the laser fluence above 1.5 J/cm² the polyepichlorohydrin films present deviations from the bulk polymer.Morphological investigations (atomic force microscopy and scanning electron microscopy) reveal continuous polyepichlorhydrin thin films for a relatively narrow range of fluences (1-1.5 J/cm²).The wavelength dependence of the refractive index and extinction coefficient was determined by ellipsometry studies which lead to new insights about the material.The obtained results indicate that pulsed laser deposition method is potentially useful for the fabrication of polymer thin films to be used in applications including electronics, microsensor or bioengineering industries.     

等离子体辅助制备窄带滤光片

研究了采用等离子辅助技术制备窄带滤光片的工艺。介绍了等离子辅助蒸镀系统的基本工作原理,描述了优化膜厚均匀性的过程。在有色玻璃上制备了由多层TiO2和SiO2薄膜组成的窄带滤光片,测试并分析了窄带滤光片的性能。试验结果表明,采用等离子体辅助蒸镀技术能够批量制备具有优良光学性能的窄带滤光片。     

Optical and electrical properties of SnO2:Sb thin films deposited by oblique angle deposition

The antimony doped tin oxide (SnO₂:Sb) (ATO) thin films were prepared by oblique angle electron beam evaporation technique. X-ray diffraction, field emission scanning electron microscopy, UV-vis-NIR spectrophotometer and four-point probe resistor were employed to characterize the structure, morphology, optical and electrical properties. The results show that oblique angle deposition ATO thin films with tilted columns structure are anisotropic. The in-plane birefringence of optical anisotropy is up to 0.035 at α = 70°, which means that it is suitable as wave plate and polarizer. The electrical anisotropy of sheet resistance shows that the sheet resistance parallel to the deposition plane is larger than that perpendicular to the deposition plane and it can be changed from 900 Ω/□ to 3500 Ω/□ for deposition angle from 40° to 85°, which means that the sheet resistance can be effectively tuned by changing the deposition angle. Additionally, the sandwich structure of SiO₂ buffer layer plus normal ATO films and oblique angle deposition ATO films can reduce the resistance, which can balance the optical and electrical anisotropy. It is suggested that oblique angle deposition ATO thin films can be used as transparent conductive thin films in solar cell, anti-foggy windows and multifunctional carrier in liquid crystal display.     

反应离子镀光学薄膜的微观结构分析

用反应离子镀方法制备了ＴｉＯ２单层膜及ＴｉＯ２／ＳｉＯ２多层膜，用透射电子显微镜分别观察了由反应离子镀方法及传统蒸镀法二种不同工艺制得的ＴｉＯ２单层膜及ＴｉＯ２／ＳｉＯ２多层膜的断面结构，并对ＴｉＯ２单层膜进行了喇曼分析和卢瑟福背散射分析。     

Influence of the substrate hydrophilicity on the grid assisted deposition of tris-(8-hydroxyquinolinato) aluminum(III) thin films

The influence of the substrate wetting properties on the grid assisted deposition of tris-(8-hydroxyquinolinato)aluminum(III) (Alq₃) onto Si/SiO_x surfaces was investigated. Different degrees of hydrophilicity/hydrophobicity on the Si/SiO_x were obtained by changing the surface chemical functionalities with wet treatments. We observed that the deposited Alq₃ films can be spatially controlled and assembled either into continuous grid-like stripes or ordered dots depending upon the wetting properties of the substrate.     

The effect of hydrogen on copper nitride thin films deposited by magnetron sputtering

Copper nitride thin films were deposited on Si (1 0 0) wafers by reactive magnetron sputtering at various H₂/N₂ ratios. X-ray diffraction measurements show that the films are composed of Cu₃N crystallites with anti-ReO₃ structure and exhibit preferred orientation of [1 0 0] direction. Although the relative composition of the films has obviously changes with the H₂/N₂ ratios, the orientations of the films keep almost no changes. However, the grain size, lattice parameter and composition of the films are strongly dependent on the H₂/N₂ ratios. The copper nitride films prepared at 10% H₂/N₂ ratios show poor stability and large weight gain compared to the copper nitride films prepared at 0% H₂/N₂ ratios.     

Excimer laser deposition of thin amorphous carbon films

A new carbon film deposition technique, based upon excimer laser vaporization of graphite in a flowing gas system has been developed. The low temperature vapor (LTV) technique alleviates high temperatures occurring in most other deposition methods. In this technique the UV laser ablation occurs in an inert flowing gas atmosphere. Atoms and molecules evaporated from graphite are cooled by gas entrainment before condensing on a substrate. The resulting films of amorphous carbon or hydrogenated amorphous carbon are free from strain. Measurement of the optical band gap of these films shows that E_g can be controlled by the hydrogen content of the carrier gas.     

Microstructure and photoluminescence of Er-doped SiOx films synthesized by ion beam assisted deposition

Er-doped SiO_x films were synthesized at 500℃ by ion beam assisted deposition technique and annealed at 800 and 1100℃ for 2h in the air atmosphere. The analysis by using energy dispersive x-ray spectroscopy showed that the ratio of Si to O decreased from 3 in the as-deposited films to about 1 in the annealed films. The investigation by using transmission electron microscopy and x-ray diffraction indicated that annealing induces a microstructure change from amorphous to crystalline. The grain sizes in the films were about 10 and 40nm when annealed at 800 and 1100℃, respectively. The films annealed at temperatures of 800 and 1100℃ exhibited a sharp photoluminescence (PL) at 1.533μm from the Er centres when pumped by 980nm laser. The influence of microstructure and grain size on the PL from Er-doped SiO_x films has been studied and discussed.     

Effects of deposition temperature on the structural and morphological properties of thin ZnO films fabricated by pulsed laser deposition

ZnO thin films were grown on Si(1 0 0) substrates using pulsed laser deposition in O₂ gas ambient (10 Pa) and at different substrate temperatures (25, 150, 300 and 400 °C). The influence of the substrate temperature on the structural and morphological properties of the films was investigated using XRD, AFM and SEM. At substrate temperature of T=150 °C, a good quality ZnO film was fabricated that exhibits an average grain size of 15.1 nm with an average RMS roughness of 3.4 nm. The refractive index and the thickness of the thin films determined by the ellipsometry data are also presented and discussed.