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In the past several years, CH₃NH₃PbI₃ perovskite material has been extensively evaluated as an absorber layer of perovskite solar cells due to its excellent structural and optical properties, and greater than 22% conversion efficiency. However, improvement and future commercialization of solar cells based on CH₃NH₃PbI₃ encountered restrictions due to toxicity and instability of the lead element. Recently, studies on properties of lead-free and mixture of lead with other cations perovskite thin films as light absorber materials have been reported. The purpose of this paper was the fabrication of CH₃NH₃Sn₁-xPbxI₃ thin films with different SnI₂ concentrations in ambient condition, and study on the structural, morphological, optical, and photovoltaic performance of the studied solar cells. The X-ray diffraction studies revealed the formation of both CH₃NH₃PbI₃ and CH₃NH₃SnI₃ phases with increasing the Sn concentration, and improvement in crystallinity and morphology was also observed. All perovskite layers had a relatively high absorption coefficient >104 cm⁻¹ in the visible wavelengths, and the bandgap values varied in the range from 1.46 to 1.63 eV. Perovskite solar cells based on these thin films have been fabricated, and device performance was investigated. Results showed that photo-conversion efficiency (PCE) for the pure CH₃NH₃PbI₃sample was 1.20%. With adding SnI₂, PCE was increased to 4.48%.

In this work, the author mixed tin and lead with different percentages in the perovskite thin film. Also, the preparation of these layers and also other layers to fabricate solar cells based on them were conducted in an open and non-glove box environment. Finally, the effect of [Sn/Pb] ratio in the CH₃NH₃Sn₁-xPbxI₃ layers on the structural, morphological, optical, electrical and photovoltaic performance have been investigated.

CH₃NH₃Sn₁-xPbxI₃ (x = 0.0, 0.25, 0.50, 0.75, 1.0) perovskite thin films have been grown by a spin-coating technique. It was found that as tin concentration increases, the X-ray diffraction and FESEM images studies revealed the formation of both CH₃NH₃PbI₃ and CH₃NH₃SnI₃ phases, and improvement in crystallinity, and morphology; all thin films had high absorption coefficient values close to 104 cm⁻¹ in the visible region, and the direct optical bandgap in the layers decreases from 1.63 eV in pure CH₃NH₃SnI₃ to 1.46 eV for CH₃NH₃Sn0.0.25Pb0.75I3 samples; all thin films had p-type conductivity, and mobility and carrier density increased; perovskite solar cells based on these thin films have been fabricated, and device performance was investigated. Results showed that photo-conversion efficiency (PCE) for the pure CH₃NH₃PbI₃sample was 1.20%. With adding SnI2, PCE was increased to 4.48%.

The preparation method seems to be interesting as it is in an ambient environment without the protection of nitrogen or argon gas.

The purpose of this paper is to identify, study and quantify the effects of lighting on yield and productivity in manual electronics assembly (MEA) and inspection as a limiting work design criterion. The study also examines the potential interactions among lighting option, workers' age, and years of experience.

A three‐factor full factorial experiment is adopted to statistically evaluate the independent variables (process yield and assembly time) versus randomly selected levels of three factors: type of light (low pressure sodium, mercury vapor lamps, and metal halide lamps measured in foot‐candle luminaries), operator age, and years on the job. A residual analysis is also conducted to complement and corroborate the ANOVA findings.

The study finds that metal halide lamps, based on the ANSI recommended ranges of 186‐464 foot‐candles, lead to significant increases in labor productivity and through‐put, irrespective of operators' age and years of experience. Although these lamps have a significantly shorter life span than that of low‐pressure sodium and mercury vapor lamps, the realized benefits far exceed the incremental cost of illumination devices. The results indicate that a modest capital investment is able to generate solid improvements in yield and processing time in a typical MEA environment.

The relations between productivity and lighting intensity and type have never been studied in the area of MEA. This empirical study uncovers the effects through a systematic experimentation of this essential relationship in a typical MEA environment. The findings, which can be generalized to other facilities, are validated by an array of statistical procedures and proved to be significant. The paper contributes useful knowledge to the fields of engineering management and facility design.

Greenwood Electronics Makers of the Oryx range of soldering tools and equipment, Greenwood Electronics have recently appointed John Polden as Managing Director. Formerly General Manager of the Microelectronics Division of Welwyn Electronics, Mr Polden is a qualified electronics engineer and has worked in electronics design with the Ministry of Defence. Prior to his eight years with Welwyn, he obtained a Master's degree in business studies at the London Business School.

As the feature sizes of microelectronic and optoelectronic components continue to decrease, there has been increased interest in developing new techniques for etching the materials used to construct these highly integrated components. Features of the new techniques now being investigated include etching with neutral species, maskless processing, material selectivity, and reduced electrical damage.

The purpose of this study is the synthesis and characterization of a CMYK palette (cyan of Cr-BiVO₄, magenta of Pr-CeO₂, yellow of Bi-(Ce,Zr)O₂ composite and black of YMnO₃) as an eco-friendly polyfunctional palette that combines (a) high near-infrared reflectance (cool pigments) that allows moderate temperatures in indoor environments and the urban heat island effect; (b) photocatalytic activity for the degradation of organic contaminants of emerging concern of substrates in solution (such as Orange II or methylene blue) and gaseous (NO_x and volatile organic compounds such as acetaldehyde or toluene); (c) X-ray radiation attenuators associated with bismuth ions; and (d) biocidal effect combined with co-doping with bactericidal agents.

Pigments were prepared by a solid-state reaction and characterized by X-ray diffraction, diffuse reflectance spectroscopy, photocatalytic activity over Orange II and scanning electron microscopy.

The behaviour of the proposed palette was compared to that of a commercial inkjet palette, and an improvement in all functionalities was observed.

The functionalities of pigments allow the building envelope and indoor walls to exhibit temperature-moderating effects (with the additional effects of moderating global warming and increasing air conditioning efficiency), purification and disinfection of both indoor and outdoor air, and radiation attenuation.

The proposed palette and its polyfunctional characterization are novel.

ISHM‐Benelux held its 1987 Autumn Conference on 29 October, at the Antwerp Crest Hotel. This one‐day meeting focused on applications of hybrid circuit technology in various fields of electronic and related industries.

The purpose of this paper is to provide a systematic review on technical findings and discuss the feasibility and future of gold (Au) wirebonding in microelectronics packaging. It also aims to study and compare the cost, quality and wear-out reliability performance of Au wirebonding with respect to other wire alloys such as copper (Cu) and silver (Ag) wirebonding. This paper discusses the influence of wire type on the long-term reliability tests.

Literature reviews are conducted based on cost and wire selections of Au, Cu or Ag wirebonding. Detailed wear-out failure findings and wire selection with cost considerations are presented in this review paper. The future and the status of Au wirebonding in microelectronics packaging are discussed in this paper.

This paper briefly reviews selected aspects of the Au ball and other alternative bonding options, focusing on reliability performance, and discusses the future of Au wirebonding in the near future in semiconductor packaging.

The paper reveals the technical considerations when choosing the wire types for future microelectronics packaging.

The in-depth technical review and strategies of the selection of wire types (Au, Cu or the latest Ag alloy) in microelectronics packaging are discussed in this paper based on previous literature studies.

Two die attach adhesive products, manufactured by Furane Products Co., claim to meet the military specification for epoxy electronic adhesives (MIL‐STD‐883C, Method 5011) without exception. The products are EPIBOND 7002 which is a thermally conductive adhesive and EPIBOND 7200, an electrically and thermally conductive die attach adhesive. Both are 100% solids and contain no solvents or diluents. Consequently, the likelihood of outgassing and void formation is greatly reduced. Both are extremely high purity systems, and have a hot die‐shear strength of over 6,000 N/M2 at 150°C. Both materials are screen printable and undergo virtually no bleed‐out during processing.

To review recent developments in machine vision hardware and techniques, as revealed in the Image Processing and Optical Technology Exhibition, 2006.

Different sections of the paper examine new cameras and their interfacing, smart cameras with DSP processors, a powerful framegrabber, high intensity light emitting diode (LED) lighting, and developments in teraherz sources and detection.

Smart cameras now exist with greater processing speed than a PC. A new generic programming interface aims to ease the incompatibilities of digital cameras. Water cooling has produced a very intense and long life LED light, and a novel goniophotometer has no moving parts. Rapid advances are occurring in the field of terahertz imaging.

Provides an update on machine vision technology for scientists and engineers generally, and a source of contact information for specialists to follow up where necessary.

‘Soldering and Cleaning in Electronics’ international conference, including an exposition, took place in Brno on 12–13 October 1993. The conference was organised by SMT‐Info, together with the ISHM‐Czech and Slovak Chapter. The purpose of this common action was to bring together the professionals in surface mount technology and thick film technology. In the framework of the conference, in which 130 home and foreign delegates participated, the annual meeting of the ISHM‐Czech and Slovak Chapter took place.