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To give an introductory overview of the key issues that need to be addressed when manufacturing PCBs in China for the European market.

The paper gives an overview of key issues impacting manufacturers supplying printed circuit boards into Europe. The demand for higher performance and the need to comply with legislation such as the European RoHS Directive are posing significant challenges for non‐European fabricators. The paper introduces some of the key issues including materials substitution, the move to lead‐free assembly and new laminate requirements in the context of increasingly stringent quality and performance criteria.

Low cost manufacturers in China supply a large proportion of the PCBs used by the European electronics industry. If this supply is to continue as board complexities and performance requirements increase, PCB fabricators will need to pay careful attention to a wide range of issues including European legislation, choice of laminates, reliability and manufacture in compliance with industry specifications. Failure to meet these requirements will be costly and could result in the loss of European sales opportunities.

There are significant challenges for overseas board manufacturers wishing to supply an increasingly demanding European market. Strategic alliances with partners in Europe can offer one route for better understanding these demands and meeting customer requirements without incurring unnecessary costs.

The paper attempts to highlight some of the issues and potential problem areas that need to be addressed when using low cost manufacturing routes to supply high quality circuit boards into the European market.

To present an overview of the current status of the RoHS directive and its implications for the printed circuit board (PCB) industry.

A review paper detailing the requirements of the RoHS directive, the materials that are proscribed, where they are found and the impacts on PCB fabrication and assembly.

The main implications of RoHS for the PCB industry are related to the proscription of lead and the move to lead‐free assembly. Tin‐lead HASL finished boards will no longer be allowed and new laminates may be needed to accommodate the higher soldering temperatures associated with lead‐free assembly. There is growing pressure to move away from the use of brominated flame retardants, even though the standard materials used in FR4 type laminates are not proscribed.

Manufacturers need to be aware of the implications of the RoHS directive, not just in terms of compliance but also from a materials selection and reliability perspective.

The paper details how the RoHS directive impacts PCB manufacturing and assembly and highlights the changes needed to enable reliable lead‐free assembly within the context of legislative compliance. Actions necessary to ensure compliance are also detailed.

Increasing awareness of man's impact on the environment and pressure to behave in a more sustainable manner are encouraging both the recycling and reuse of materials and the replacement of hazardous chemicals with more benign ones. The Waste Electrical and Electronic Equipment (WEEE) Directive and the Restriction on the use of certain Hazardous Substances in Electrical and Electronic Equipment (RoHS) Directive, have recently been adopted into law with the specific intention of further encouraging these activities through legislation. In addition to these directives, there is a growing need to adopt sound design principles so that new products are created in a more environmentally acceptable way and that their environmental impact throughout their lifecycles is minimised. This paper gives an overview of this new European legislation and discusses its impact on the electronics industry. The potential benefits of adopting such an approach are outlined.

Tin‐lead solder has been the primary method for connecting electronic components to printed circuit boards since near the time of its inception. Over the last 60 years, solder has proven a viable assembly method over that time and there is a deep understanding of the technology won over years of practice. However, the European Union has banned the use of lead in electronic solder, based on the misguided assumption that lead in electronic solder represented a risk to human health. Aims to describe a new approach to manufacturing electronic assemblies without the use of solder.

The paper discusses how the new era of lead‐free solder has resulted in a host of new problems for the electronics industry, many of which had not been experienced when elemental lead was included in the solder alloy.

Electronics assembly technology literature is rife with articles and papers citing the problems or challenges of lead‐free assembly and proposing new or improved solutions or investigative tool to better unearth the problems of lead‐free. The new process has come to be known as the Occam process, named to honor the fourteenth century English philosopher and logician, William of Occam, whose rigorous thinking and arguments in favor of finding the simplest possible solution served as the inspiration and catalyst for the new approach.

The paper describes a new approach to manufacturing electronic assemblies without the use of solder.

Over the last few years, the emergence of new European draft legislation has focussed electronics industry attention on the likely ultimate proscription of lead in electronics assembly. Much work has already been undertaken to identify the possible alternatives to conventional tin‐lead solders and to evaluate their performance benefits and limitations in comparison with the traditional materials. Although, some companies are already offering products manufactured using lead‐free products, there is still a widespread lack of activity in many areas. With this none‐too‐distant deadline rapidly approaching, Envirowise has sponsored this paper as part of its coordinated activities to assist the UK electronics industry and to promote environmental efficiency and best practice. This paper details the current situation with respect to the drivers towards the adoption of lead‐free assembly before giving an overview of the current situation. This paper concludes with details of sources of further information.

Printed circuit boards (PCBs) requiring component attachment, whether leaded or surface mount technology, must have the exposed copper land areas coated with a protective finish. This protective coating must not inhibit solderability and at the same time must act as a barrier for preventing the copper from oxidizing and the inevitable assembly problems that would ensue for the end‐user. Globally, the predominant surface finish in the PCB industry is hot air solder levelling (HASL). Driven by the adoption of solder mask over bare copper, HASL was developed as a reliable method of applying solder to the copper surfaces after solder mask. During HASL, a thin layer of solder is deposited onto the exposed copper by passing the boards through a hot, molten wave (or pot) of solder and subsequently blowing the excess solder from the boards using high velocity hot air. This process has been increasingly under scrutiny due to environmental and safety issues (hazardous waste, lead exposure, etc.), technological limitations (fine‐pitch device assembly) and equipment maintenance cost. This paper reviews the major alternative surface finishes being currently deployed and additionally seeks to give an overall assessment of the broader environmental aspects of such finishes.

The aim of this paper is to detail the changes needed to ensure compatibility of printed‐circuit board (PCB) surface finishes with the use of lead‐free solders and in lead‐free assembly processes.

The paper describes the various popular solderable surface finishes that are currently available. It then reviews them in terms of the required adaptations necessary to meet the requirements of the Restriction of Hazardous Substance (RoHS) Directive and to ensure compliance, whilst meeting the performance needs of the product.

Some of the available and popular finishes, such as organic solderability preservatives and tin require modifications while, others including silver, direct immersion gold and electroless nickel immersion gold are transitioning well into the world of lead‐free. Electroless nickel, electroless palladium, immersion gold is one finish that performs better with lead‐free assembly than it did with conventional eutectic solder‐based approaches.

The paper provides a concise overview of the implications for specific surface finishes when making choices for use with lead‐free and RoHS compliant PCB soldering and assembly.

To give an overview of the issues encountered, and changes that need to be made in the various types of soldering process when converting them from conventional to lead‐free assembly.

This paper has been written to provide a review of the lead‐free reflow, wave and hand soldering processes. Problem areas highlighted and methods for adjusting and optimising each type of soldering process for compatibility with lead‐free solders are described.

The move to lead‐free soldering in electronics assembly can lead to a number of issues that affect process performance, yields and reliability. Problems that are sometimes encountered with conventional lead‐bearing solders can exacerbated when moving to lead‐free. Many of the issues are associated with the higher melting points of the recommended lead‐free solders. Fortunately, these issues are now well known and, with care and attention to process optimisation, they can largely be avoided.

The value of the paper lies in its ability to provide information on the types of problems and issues encountered when moving to lead‐free solders and the advice it gives on how to avoid them. It also describes how to convert the various lead‐free soldering processes used in PCB assembly using a range of measures that can minimise defects, avoid common problems and optimise yields. Sources of additional assistance are also identified.

A distinction must be drawn between a dismissal on the one hand, and on the other a repudiation of a contract of employment as a result of a breach of a fundamental term of that contract. When such a repudiation has been accepted by the innocent party then a termination of employment takes place. Such termination does not constitute dismissal (see London v. James Laidlaw & Sons Ltd (1974) IRLR 136 and Gannon v. J. C. Firth (1976) IRLR 415 EAT).