Cu-In-Ga-Se nanoparticle colloids as spray deposition precursors for Cu(In, Ga)Se2 solar cell materials

The use of nanoparticle colloids for spray deposition of Cu(In,Ga)Se₂ (CIGS) precursor films and subsequent fabrication of CIGS solar cells has been investigated. According to this approach, amorphous Cu-In-Ga-Se nanoparticle colloids were first prepared by reacting a mixture of CuI, InI₃, and GaI₃ in pyridine with Na₂Se in methanol at reduced temperature. Purified colloid was sprayed onto heated molybdenum-coated sodalime glass substrates to form Cu-In-Ga-Se precursor films. After thermal processing of the precursor films under a selenium ambient, CIGS solar cells were fabricated. Cu-In-Ga-Se colloids and films were characterized by inductively coupled plasma atomic emission spectroscopy, thermogravimetric analysis, transmission electron microscopy, x-ray diffraction, scanning electron microscopy, and Auger electron spectroscopy. Standard current-voltage characterization was performed on the CIGS solar cell devices with the best film exhibiting a solar conversion efficiency of 4.6%.     

Synthesis of In2S3 thin films by spray pyrolysis from precursors with different [S]/[In] ratios

Indium sulfide （InzS3） thin films were prepared by chemical spray pyrolysis technique from solutions with different [S]/[In] ratios on glass substrates at a constant temperature of 250 ~C. Thin films were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, atomic force microscopy （AFM）, energy disper- sive X-ray spectroscopy （EDS）, Raman spectroscopy and optical transmittance spectroscopy. All samples exhibit a polycrystalline structure with a preferential orientation along （0, 0, 12）. A good stoichiometry was attained for all samples. The morphology of thin film surfaces, as seen by SEM, was dense and no cracks or pinholes were ob- served. Raman spectroscopy analysis shows active modes belonging to j3-1naS3 phase. The optical transmittance in the visible range is higher than 60% and the band gap energy slightly increases with the sulfur to indium ratio, attaining a value of 2.63 eV for [S]/[In] ： 4.5.     

The effect of film thickness and doping content of SnO2:F thin films prepared by ultrasonic spray method

This paper reports on the effects of film thickness and doping content on the optical and electrical properties of fluorine-doped tin oxide. Tin (II) chloride dehydrate, ammonium fluoride dehydrate, ethanol and HCl were used as the starting materials, dopant source, solvent and stabilizer, respectively. The doped films were deposited on a glass substrate at different concentrations varying between 0 and 5 wt% using an ultrasonic spray technique. The SnO₂:F thin films were deposited at a 350 ℃ pending time (5, 15, 60 and 90 s). The average transmission was about 80%, and the films were thus transparent in the visible region. The optical energy gap of the doped films with 2.5 wt% F was found to increase from 3.47 to 3.89 eV with increasing film thickness, and increased after doping at 5 wt%. The decrease in the Urbach energy of the SnO₂:F thin films indicated a decrease in the defects. The increase in the electrical conductivity of the films reached maximum values of 278.9 and 281.9 (Ω·cm^-1) for 2.5 and 5 wt% F, respectively, indicating that the films exhibited an n-type semiconducting nature. A systematic study on the influence of film thickness and doping content on the properties of SnO₂:F thin films deposited by ultrasonic spray was reported.     

PCB喷淋系统应用浅谈

文章针对PCB厂水平线如何计算、选择合适的喷嘴进行了初步的探讨,并结合实际应用展示了选择合适的喷淋系统,以有利于生产品质的提升。     

Piezoelectric zinc oxide by electrostatic spray pyrolysis

Zinc oxide (ZnO) possesses many interesting properties, such as a wide energy band gap, large photoconductivity, and high excitonic binding energy. Piezoelectric (ZnO) film has a high electro-mechanical coupling coefficient, which makes it a promising material for high frequency and low surface acoustic wave (SAW), bulk acoustic wave, and microelectromechanical system devices. In this work, we present the first results obtained for piezoelectric ZnO thin films prepared on corning 7059 glass substrate by electrostatic spray pyrolysis (ESP), a simple, cheap and efficient technique not widely used for ZnO deposition, using zinc nitrate in a mixture of deionised water and isopropyl alcohol. The structural morphologic and optical properties of the films have been studied and the effect of the preparation conditions, such as substrate temperature and substrate-nozzle distance, discussed. Highly c-axis preferred orientation, which is critical for piezoelectric applications (ultrasonic oscillators and transducers devices), ZnO thin films are obtained at 350 °C growth temperature and at 4.5 cm substrate-nozzle distance.     

Mechatronic design of a leather spray system

Leather skins require a variety of processing steps. Many leather products require coatings such as paints and lacquer to enhance appearance, protect the surface and mask minor visual defects. The coatings are often applied by spraying. For large production volumes, automated machinery is readily available. For small factories finishing leathers in Hong Kong, large production lines are too costly and bulky. Most small leather processors spray coatings manually, requiring skilled workers to produce high quality products. Such skilled workers are in short supply due to the potential health risks of the job. A system to automate the spraying of coatings on leathers has been designed and a prototype system implemented to assess the feasibility. A safe, compact machine, adaptable to the factory environment and space available giving good spraying quality, having low maintenance requirements, capable of manual control as well as automatic spraying was required. The following design features were achieved in the prototype system: selectable automatic and manual operation; remote control; explosion safe; paint conservation; adjustable spray nozzle height; fast spraying operation; high quality spraying; compact size; safety; low cost; reliability; and energy conservation.     

含有添加剂的喷雾冷却研究进展

喷雾冷却是解决电子元器件等高热流密度散热问题的关键技术。综述了在纯工质中添加纳米颗粒、表面活性剂、可溶性盐和气体以及醇类等添加剂对喷雾冷却换热性能的影响,介绍了不同类型添加剂影响换热的机理和限制换热的因素,并提出了一些可行的解决方案。指出了对含有添加剂的喷雾冷却的研究方向和应用前景。     

脉冲式喷雾冷却的实验研究进展

脉冲式喷雾冷却是解决现在大功率电子设备散热问题的最理想方法之一,具有能够大幅度提高电子元器件换热效率的潜能。介绍了脉冲式喷雾冷却相比传统连续喷雾冷却所具有的优点,综述了国内外对脉冲式喷雾冷却的研究,总结了占空比、频率及喷雾周期对热表面换热效率的影响。最后总结了现阶段关于脉冲式喷雾冷却的研究结论并展望了未来的研究方向。     

以喷淋方式考察抗氧化护铜剂(OSP)的处理方法

近年来,"抗氧化护铜剂(又名有机预焊剂,水溶性耐热前处理型助焊剂,以下称OSP)"很广泛地应用于印制线路板的最终表面处理。一方面,印制线路板正急速地朝向小型化,高密度化发展,且已出现了焊盘最表面的阻焊膜孔径为100微米(μm)以下(以下称微小径焊盘)的印制板。但在传统的浸泡处理下,OSP很难渗透到微小径焊盘内。因此,无法充分形成皮膜,在封装工序中无法保持良好的可焊性,导致封装不良的结果。然而,在OSP处理工序中,对上述问题至今没有找到有效的解决方案。为了解决这些问题,我们以喷淋方式进行了OSP处理。通过选择适当的喷嘴进行喷淋处理,把喷射的OSP粒径调整到50微米以下,使OSP药液容易渗透到微小径焊盘内。但是,由于还存在着调整温度的难度,接液量及时间不足等问题,我们考虑到有可能无法在铜表面上充分形成OSP皮膜。因此,通过在低温下迅速形成皮膜的OSP处理,实现了以少量且短时间的喷淋充分形成皮膜。     

静电雾化场的数字全息实验研究

为了获取静电雾化场中雾滴的空间位置、尺寸和速度信息,利用同轴数字显微全息方法,设计并搭建了雾化场测量装置,横向测量范围Ø12.5mm,空间极限分辨率90.5LP/mm,能够实现直径8μm雾滴的测量。在该装置上,进行了单毛细管和多毛细管在稳定锥-射流模式下雾化场的测量,取得了不同流量下雾滴平均直径和平均速度随流量的变化关系。结果表明,该装置能够在单次测量中同时给出雾滴空间位置、尺寸和速度信息。该研究对于雾化参量的测量以及静电雾化研究有重要意义。     

燃油喷雾内部构造可视化的激光CT技术(2)——对柴油机喷雾的应用

本文介绍了作者设计的燃油喷雾的激光CT测试系统,其中采用红宝石脉冲激光器作光源,CCD(Charge coupled device)摄象机作探测器,并配置了P540数字图象处理系统。利用红宝石脉冲激光和CCD的特性,实时地将燃油喷雾采集到数字图象处理系统上。用ART对喷雾图象进行重建,成功地实现了燃油喷雾内部构造的三维可视化。     

热喷涂界面的观察与分析

在表面工程技术中，涂层和基体的界面性质直接影响到工件的综合性能[1]。热喷涂技术由于简单易行，是应用最为广泛的表面工程技术之一。     

铁路油罐车洗涤液喷淋清洗

评述了一种用特效清洗液清洗铁路油罐车的新工艺.通过试验筛选出一种对油污及蜡油的溶解吸收有特效的清洗液.并对清洗工艺进行了摸拟试验.结果表明:使用该清洗液对油罐清洗作业不仅可行,而且具有费用低,省时、省力和良好的清洗效果,不失为一种有效、经济、实用的清洗工艺.     

基于参数自整定的沥青洒布量控制

根据比例因子与系统性能的关系和整定原则,得到可行的整定规则表,对沥青撒布控制系统采用了参数自整定模糊控制算法控制喷洒的压力,实现了洒布量的稳定精确控制,提高了洒布质量和生产效率。     

沥青温拌定量喷洒装置的设计

介绍了沥青温拌定量喷洒装置的结构,采用PLC对沥青温拌定量喷洒装置的电气系统进行控制,同时依靠触摸屏完成系统状态监视和过程控制,通过PLC及组态软件MCGS实现温拌添加剂无人工操作、完全自动化的定量喷洒,具有控制精度高、自动,手动灵活切换的优点。     

喷雾冷却换热机理研究进展

喷雾冷却因温度均匀性高,散热功率大的特点在电子元器件散热领域备受关注,但目前对喷雾冷却换热机理的研究尚未得出能够被普遍认可的结论。本文综述了液膜蒸发、强迫对流、表面核态沸腾、二次核化这四种认可度较高的换热机理,指出了相应的换热模型;并以换热机理为基础指出了强化换热的方式。     

Effects of salt spray test on lead-free solder alloy

This paper starts with a bibliographic survey about solder corrosion and experimental results of the corrosion on lead-free solder balls during salt spray tests. Focus is made on the SnAgCu solder alloy. Ball Grid Array assemblies and “Package on Package” components were put up to 96 h in a salt spray chamber at 35 °C with 5% sodium chloride (NaCl) aqua according to the ASTM B117-09 standard. The weight is measured during the test. The solder alloys are observed and analysed along the ageing with optical microscope and scanning electron microscope equipped with an energy-dispersive x-ray system. The solder alloy deterioration is visible after 48 h. The microstructure is analysed in order to determine the corroded residues found on the surface solder balls after the salt spray test. Tin oxychloride (Sn(OH)Cl) is found on BGA solder joints after reflow and on PoP solder balls before reflow. The size of the solder balls has an influence on the corrosion state. Finally a method is developed in order to measure the corrosion product growth on the same sample during the salt environment exposure.     

Chip-level spray cooling of an LD-MOSFET RF power Amplifier

We report here the application of water spray cooling directly to the top surface of a lateral diffused metal oxide semiconductor field effect transistor (LD-MOSFET) in a 500-MHz RF power amplifier. With the amplifier running in Class A, spray cooling at a flow of 0.14 l/min increases the output power from 66 W to 84 W, and the power-added efficiency increases from 26% to 34%, all at 34 W input. This improvement is attributed to a large spray-induced reduction in junction temperature and total package thermal resistance. At the point of highest measured RF output and DC power dissipation, the reduction in junction temperature and total thermal resistance were estimated to be from /spl ap/214/spl deg/C to /spl ap/115/spl deg/C and from /spl ap/1.5/spl deg/C/W to /spl ap/0.6/spl deg/C/W, respectively, and the maximum spray-induced heat flux was /spl ap/162W/cm/sup 2/. In Class AB, the increase in output power and power-added efficiency are less, /spl ap/8%, but the amplifier can be driven harder before failure occurs. The maximum output in class AB is 79 W compared to 70 W without spray cooling.     

Topographical and morphological aspects of spray coated organic photovoltaics

Herein we discuss the topographical and nanomorphological aspects of spray deposited organic photovoltaics. We show that the solvent properties have a massive impact on the topography, but less on the nanomorphology formation of composites based on the electron donor poly(3-hexylthiophene) (P3HT) and the electron acceptor [6,6]-phenyl C61 butyric acid methyl ester (PCBM). An adapted solvent mixture consisting of ortho-dichlorobenzene (oDCB) and 1,3,5-trimethylbenzene (mesitylene) allows us to demonstrate spray coated organic photovoltaic devices with 3.1% power conversion efficiency (PCE). Moreover, we show that spray coating is a feasible technology to deposit all solution processable layers of organic solar cells, including the hole transporting layer poly(3,4-ethylene dioxythiophene) doped with polystyrene sulphonic acid (PEDOT:PSS) as well and demonstrate fully spray coated devices with 2.7% PCE.