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Over the past few years there has been increasing utilisation of higher density surface mounting on printed wiring boards. As components and pads decrease in size, the topography of the solder mask relative to the conductors becomes an important solderability issue. There exists convincing evidence that thinner, more conformal solder mask geometries improve soldering yields of both stencilled and wave soldered surface mount components. In order to provide the solder mask coverage required for improved assembly performance, the authors critically compared several commercially available solder mask coating technologies. The coating methods were appraised according to both assembly and printed wiring board manufacturing criteria. Within this programme, seven liquid photoimageable solder masks were also evaluated. The materials were rated according to their final cured properties (electrical, mechanical, chemical performance), their manufacturability in the printed wiring board manufacturing process (maximum throughput, major defects, etc.) and their performance in assembly operations (soldering yields, propensity to ‘solder ball’ formation, white residues, scratches, etc.). The information obtained was used to choose a solder mask strategy which would not only improve assembly efficiency but also increase PWB manufacturing yields and flexibility.

This study aims to examine the effects of perceived product–brand fit and brand type on consumer evaluations of wearable smart masks’ technological, aesthetic and social attributes and how these affect consumers’ attitudes and intentions to use.

Through an experimental approach, a total of 240 US consumers’ evaluations of smart masks are compared according to perceived product–brand fit (high vs low) and brand type (electronics vs fashion).

The results showed that high perceived product–brand fit increases consumers’ evaluations, while brand type did not significantly affect consumers’ evaluations. Among various attributes, social acceptability had the greatest influence on consumers’ attitude and intention to use. Perceived ease of use, however, positively influenced attitude but negatively influenced intention to use.

As consumers’ interest in smart health-care wearables increases and air pollution is a serious issue across countries, research on wearable smart masks is being facilitated. Smart masks refer to the digitalized, reusable wearable masks that provide protection and health-care functions. However, their market penetration is still limited. To close this gap between smart mask technology and the market, this study examines how perceived fit and brand type can be used to enhance consumer evaluations.

Mr Peter Lenk has transferred from the Fraunhofer‐Institut to mls munich laser systems since 1 July 1987. Prior to this move, Mr Lenk was employed at the Fraunhofer Institut für Festkörpertechnologie in Munich, where he organised and set up the procedures for the Institute's thick film technology department, supervised the complete film processing for thick film technology and research to prove the authenticity of thick film resistors. Mr Lenk also supervised and conducted training in thick film technology.

The need for high packing density has led to a requirement for photo‐imageable solder masks, and the increase in surface mount technology is rapidly expanding the use of these systems into consumer electronics in addition to the traditional high‐technology outlets. This paper compares the properties and performance of the two broad types of photo‐imageable systems—dry film solder masks and liquid systems. The manufacturing and coating requirements are outlined. Dry film solder masks are supplied by major chemical companies as high‐quality pre‐formed films while producing coatings from liquid systems is the responsibility of the printed circuit board producer. The process for producing solder masked boards from the two systems is outlined. The relative performance of the systems is compared in detail. Resolution, encapsulation, topography and reliability are considered and these are discussed as well as the requirements for fluxing and defluxing and formation of tented via holes, a highly desirable feature for SMT. Finally, the attractiveness of the more established dry film technology for surface mount boards is summarised, with a request that designers consider the features available and build these into their designs for new circuit boards. Provided the appropriate application system is used and the thickness of dry film solder mask is matched to the requirement, cost advantages can be derived from their use.

COVID-19 pandemic has exposed that even the best of the developed nations have surrendered to the devastations imposed on the global supply chains. The purpose of this study is to explore how COVID-19 has exaggerated the supply chain of production and distribution of Taiwan-based face masks and also investigate the conscientious factors and subfactors for it.

In this study, an analytical hierarchy processes (AHP)-based approach has been used to assign the criterion weights and to prioritize the responsible factors. Initially, based on 26 decision-makers, successful factors were categorized into five main categories, and then main categories and their subcategories factors were prioritized through individual and group decision-maker’s contexts by using the AHP approach.

The results of this AHP model suggest that “Safety” is the most important and top-ranked factor, followed by production, price, work environment and distribution. The key informers in this study are stakeholders which consist of managers, volunteers, associations and non-governmental organizations. The results showed that good behavior of the employees under the “Safety” category is the top positioned responsible factor for successful production and distribution of face masks to the other countries with the highest global percentage of 15.7% and using sanitizers to protect health is the second most successful factor with the global percentage of 11.7%.

The limitations faced in this study were limited to only Taiwan-based mask manufacturing companies, and it was dependent on the decisions of the limited company’s decision-makers.

The novelty of this study is that the empirical analysis of this study has been based on a successful Taiwan masks manufacturing company and evaluates the responsible factors for the production and distribution of Taiwan masks to other countries during COVID-19.

New technologies bring new challenges to those who have to convert hand‐made prototype printed circuit boards into a robust, reliable, large volume manufacturing technique. The adoption by many electronic equipment producers of surface mount technology has demanded that production managers develop and understand new skills to increase yields and obtain the maximum reliability from the product. This paper describes in some detail the methods used, many of them empirical, to obtain the best performance. Of specific interest is the importance of selecting the optimum solder mask system to increase yields and provide reliability, and the reasons for selecting a high conformance thin film solder mask are discussed. Each process is examined step‐by‐step to highlight the pitfalls, suggestions are made as to how these can be overcome and the paper concludes with the author's view of how the new technology will evolve in the future—to present further challenges to the manufacturing processes.

Recently, a Transverse Excited Atmospheric (TEA) CO2 laser technology has been developed for the micro‐machining of vias in non‐reinforced glass laminates. This system has been designed to accommodate the large panel sizes associated with PWB processing. The salient features of this modified CO2 laser technology are summarised. A joint Lumonics/Motorola study was carried out to assess the applicability of this laser processing technology for use in higher density PWB and MCM‐L substrate processing and its compatibility with currently available classes of dielectrics used in high density interconnect applications. A 10x improvement in cycle time/throughput over the existing raster scanning laser ablation process has been demonstrated.

Solder masks are used universally on high density printed circuit boards to reduce the occurrence of solder bridges between adjacent tracks and pads. The use of solder mask can, however, have a deleterious effect on the solderability, i.e., the solder pull‐through and top‐land wetting, of plated‐through‐hole boards. This work considers, quantitatively, the specific effect on PTH board solderability of solder mask, considering in turn the three classes of photoimageable dry film, photoimageable ink and screen printed ink. Two modes of solderability degradation have been identified: a geometrical effect that depends on the thickness of the mask and its encroachment around the solderable pads, and a contamination effect arising from the development and washing of the photoimageable masks from surfaces to be soldered subsequently.