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Article
Publication date: 8 February 2011

Andrew J. Cobley, Lindsay Edgar, Martin Goosey, Rod Kellner and Timothy J. Mason

Previous studies have proven that, under optimised ultrasonic conditions, a range of materials used in electronic manufacturing can be sonochemically surface modified using benign…

Abstract

Purpose

Previous studies have proven that, under optimised ultrasonic conditions, a range of materials used in electronic manufacturing can be sonochemically surface modified using benign solutions at low temperature. The purpose of this paper is to focus on a specific process, namely, the desmearing of through holes in printed circuit boards (PCB). The objective was to determine whether the introduction of low frequency ultrasound (20 kHz) to the “etch” stage of a standard “swell and etch” desmear system could enable reduced temperature processing and the use of less chemistry in the permanganate solution.

Design/methodology/approach

The study was divided into three main stages. In the first “screening” phase, the effect of ultrasound in the etch solution was studied by measuring the weight loss after desmear on a PCB laminate material (Isola 370HR). Factors such as etch temperature and concentration of permanganate (including permanganate‐free) were varied. In stage 2, confirmatory runs were carried out on the most promising conditions from the screening work and through holes in a four‐layer multi‐layer board (MLB) were assessed for smear removal using a scanning electron microscope (SEM). Finally, a four‐layer MLB was desmeared through the most promising ultrasonic process and then metallized at a PCB manufacturer. Thermal shock testing was subsequently carried out and sections from the board assessed for inter‐connection defects (ICDs).

Findings

The initial screening study indicated that, whenever ultrasound was used in the etch stage of the desmear process, significantly higher weight loss was achieved compared to a standard “silent” process. This effect was most pronounced when permanganate was removed from the etch solution and, in this situation, weight loss could be an order of magnitude higher than the silent equivalent. Further testing on through holes suggested that smear‐free inner‐layers could only be guaranteed if permanganate was present in the etch solution but that ultrasound again improved smear removal. Final testing under semi‐production conditions confirmed that, if ultrasound was employed in the etch part of the desmear process, then a reduction in processing temperature from 85°C to 60°C could be achieved and the permanganate concentration halved (65 to 33 g/L) whilst still achieving ICD‐free boards.

Originality/value

The paper indicates the feasibility of using ultrasound to reduce temperatures and chemical concentrations used in the permanganate etch solution, whilst still producing through holes with no ICDs.

Details

Circuit World, vol. 37 no. 1
Type: Research Article
ISSN: 0305-6120

Keywords

Book part
Publication date: 29 August 2018

Paul A. Pautler

The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and…

Abstract

The Bureau of Economics in the Federal Trade Commission has a three-part role in the Agency and the strength of its functions changed over time depending on the preferences and ideology of the FTC’s leaders, developments in the field of economics, and the tenor of the times. The over-riding current role is to provide well considered, unbiased economic advice regarding antitrust and consumer protection law enforcement cases to the legal staff and the Commission. The second role, which long ago was primary, is to provide reports on investigations of various industries to the public and public officials. This role was more recently called research or “policy R&D”. A third role is to advocate for competition and markets both domestically and internationally. As a practical matter, the provision of economic advice to the FTC and to the legal staff has required that the economists wear “two hats,” helping the legal staff investigate cases and provide evidence to support law enforcement cases while also providing advice to the legal bureaus and to the Commission on which cases to pursue (thus providing “a second set of eyes” to evaluate cases). There is sometimes a tension in those functions because building a case is not the same as evaluating a case. Economists and the Bureau of Economics have provided such services to the FTC for over 100 years proving that a sub-organization can survive while playing roles that sometimes conflict. Such a life is not, however, always easy or fun.

Details

Healthcare Antitrust, Settlements, and the Federal Trade Commission
Type: Book
ISBN: 978-1-78756-599-9

Keywords

Content available
Book part
Publication date: 27 November 2020

Arthur Seakhoa-King, Marcjanna M Augustyn and Peter Mason

Abstract

Details

Tourism Destination Quality
Type: Book
ISBN: 978-1-83909-558-0

Book part
Publication date: 23 July 2015

Abstract

Details

Tourism Research Frontiers: Beyond the Boundaries of Knowledge
Type: Book
ISBN: 978-1-78350-993-5

Book part
Publication date: 7 December 2016

Abstract

Details

The World Meets Asian Tourists
Type: Book
ISBN: 978-1-78560-219-1

Abstract

Details

Economics of Art and Culture Invited Papers at the 12th International Conference of the Association of Cultural Economics International
Type: Book
ISBN: 978-0-44450-995-6

Book part
Publication date: 3 February 2023

Dina Amaro, Ana Maria Caldeira and Cláudia Seabra

The twenty-first century has been characterized by the intensification of concerns related to tourism safety and security. These issues are playing an increasingly significant…

Abstract

The twenty-first century has been characterized by the intensification of concerns related to tourism safety and security. These issues are playing an increasingly significant role over recent years, due to the increase of terrorist attacks in several countries, political instability, natural disasters, epidemics and, more recently, the COVID-19 pandemic. Understanding tourist safety and security in the tourism context is, thus, critical to increasing the competitiveness and attractiveness of tourist destinations.

Through the bibliometric methods of performance analysis and science mapping, this study aims to contribute to the advancement of knowledge on tourist safety and security at the destination.

A total of 445 records published between 1989 and 2021, covering 191 academic journals and 1,000 authors from 91 different countries, were analysed.

The main findings show that this research field has attracted a substantial and growing interest of researchers, institutions, journals and countries. Opportunities for future research are related to decision making, tourist behaviour, risk perception, tourism safety, destination image, safety engineering and sustainable development.

In the post-pandemic context, this research field can be critical to providing a set of tailored strategies to improve tourists' safe destination environment and increase tourism destinations' competitiveness and attractiveness.

Book part
Publication date: 30 October 2023

Cole E. Short and Timothy D. Hubbard

As one of the most influential theories in strategic management, Hambrick and Mason’s Upper Echelons Theory has yielded significant conceptual and empirical advancements linking…

Abstract

As one of the most influential theories in strategic management, Hambrick and Mason’s Upper Echelons Theory has yielded significant conceptual and empirical advancements linking executive characteristics and perceptions to decision-making. Specifically, work on this theory consistently shows that CEOs’ decisions are biased by personal characteristics to the benefit and detriment of firms. While this stream of research links executive decision processes to outcomes such as executive dismissals, analyst evaluations, and press coverage, surprisingly little is understood about if and whether the information CEOs convey is subject to the same filtering process by a firm’s key evaluators. Thus, in this chapter, we aim to extend Upper Echelons Theory by positing that a double filtering process occurs whereby the cognitive aids CEOs use can be informed by not only their cognitive base and values but also the characteristics and priorities of those who evaluate the nonverbal and verbal signals they send. To do so, we build on recent conceptual and empirical advancements to make a case for the decision-making biases and tendencies that influence signal interpretation by three key evaluator groups internal and external to the firm: boards of directors, financial analysts, and the media. We conclude by considering the implications of evaluators’ information filtering and how this more holistic view of Upper Echelons decision-making can enable executive teams to be strategic with the cognitive aids they use to influence evaluations.

Content available
Book part
Publication date: 14 September 2018

Abstract

Details

Authenticity & Tourism
Type: Book
ISBN: 978-1-78754-817-6

Book part
Publication date: 13 May 2021

Olga Høegh-Guldberg, Sabrina Seeler and Dorthe Eide

The increasing need for the prevention and management of overtourism calls for more and improved visitor management (VM). Certain types of destinations or sites have implemented…

Abstract

The increasing need for the prevention and management of overtourism calls for more and improved visitor management (VM). Certain types of destinations or sites have implemented VM, such as nature parks that depict more controllable environments and involve only limited and clearly defined actors. Academic research on VM has mainly addressed protected areas and national parks, with a focus on environmental sustainability. The growing discussions around the term overtourism, in contrast, have largely centred around urban areas and the impacts on local societies, and, thus, socio-cultural sustainability. This chapter's overall aim is to provide a comprehensive overview of the status quo and knowledge gaps related to stakeholder involvement in VM in the broader context of overtourism. We ask who, how and in what areas stakeholders should be involved in VM. A systematic literature review was conducted using Scopus and Web of Science databases. The findings demonstrate that most studies applied a narrow and fragmented approach that focussed on one or a few stakeholders. Moreover, the strategies were mostly reactive instead of preventive and followed top-down approaches. Conflicts between stakeholders reveal risks to sustainable destination development, trigger overtourism debates and call for new approaches to VM. The chapter proposes a framework that suggests the chief VM responsibilities and stakeholders, concentrating on destination organisations, governments and residents. Also, it provides examples of participative methods, illuminates that VM should be proactive, sustainable and holistic and proposes better integration with destination management and local community governance.

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