Yuki Fukuda

The impact of lead-free legislation exemptions on the electronics industry

The European Unions Waste Electrical and Electronic Equipment legislation requires manufacturers to reduce the disposal waste of electronic products by reuse, recycling, and other forms of recovery. To enhance the possibilities and economic profitability of recycling, elimination of hazardous materials from the electrical and electronic equipments was proposed under the supplementary directive, the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment. This directive bans lead and other hazardous substances in electronics products by July 2006. However, a number of exemptions indicated in these legislations could impact different industry sectors and product categories. In this paper, the underlying basis of the legislation and the various exemptions are presented. The relevance and significance of the exemptions to the electronics industry is then analyzed and recommendations are given.

Are you ready for lead-free electronics?

An expedient transition to lead-free electronics has become necessary for most electronics industry sectors, considering the European directives [The Waste of Electrical and Electronic Equipment (WEEE) directive requires manufacturers to reduce the disposal waste of electrical and electronic products by reuse, recycling, and other forms of recovery. The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS) legislation restricts the use of lead, as well as cadmium, mercury, hexavalent chromium, and two halide-containing flame retardants, namely polybrominated biphenyls (PBB) and polybrominated diphenyl ethers (PBDE), in eight of the ten product categories identified in the WEEE directive. Unlike for WEEE, whereby EU member states are free to set more severe national legislation satisfying the WEEE directive requirements, RoHS is a single market directive. Both the WEEE and RoHS directives will become effective on July 1, 2006] , other possible legislative requirements, and market forces , . In fact, the consequences of not meeting the European July 2006 deadline for transition to lead-free electronics may translate into global market losses. Considering that lead-based electronics have been in use for over 40 years, the adoption of lead-free technology represents a dramatic change. The industry is being asked to adopt different electronic soldering materials , component termination metallurgies, and printed circuit board finishes. This challenge is accompanied by the need to requalify component-board assembly and rework processes, as well as implement test, inspection, and documentation procedures. In addition, lead-free technology is associated with increased materials, design, and manufacturing costs. [The cost of implementing the RoHS directive in the EU has been estimated to be US

The Effect of Annealing on Tin Whisker Growth

20Bn . Intel Corporations efforts to remove lead from its chips have been estimated to cost the company over US

Length Distribution Analysis for Tin Whisker Growth

100 million so far]. The use of lead-free materials and processes has also prompted new reliability concerns , as a result of different alloy metallurgies and higher assembly process temperatures relative to tin-lead soldering. This paper provides guidance to efficiently implement the lead-free transition process that accounts for the companys market share, associated exemptions, technological feasibility, product reliability requirements, and cost. Lead-free compliance, part and supplier selection, manufacturing, and education and training are addressed. The guidance is presented in the form of answers to key questions.

WEEE, RoHS, and what you must do to get ready for lead-free electronics

This paper presents a design-of-experiments study on the effect of annealing and simulated reflow on tin whisker growth. Copper, brass, and alloy 42 coupons plated with either bright or matte tin were subjected to one of three elevated temperature exposures. After the elevated temperature exposures, specimens along with a set of control specimens were then kept in room ambient conditions and monitored periodically using an environmentally scanning electron microscope. Surface observations up to 16 months of room ambient exposure revealed that tin whiskers formed on the surfaces of each specimen. However, various differences in whisker growth between the matte- and bright tin-plated specimens were observed. Columnar-type whiskers grown on the matte tin plated specimens were initiated from one grain at the surface, as opposed to the growth on bright tin which were independent from the surface morphology. Maximum length and length distribution data for matte and bright tin plating for the various exposures are presented. The result of this study shows annealing to be effective in reducing the maximum length of whiskers, particularly on bright finished coupons

The impact of electrical current, mechanical bending, and thermal annealing on tin whisker growth

The global movement to lead-free electronics has led semiconductor device assemblers to switch terminals and finishes from lead-based to pure tin or high tin lead-free alloys. This transition has resulted in a reliability concern associated with the formation of conductive tin whiskers, which can grow from a device terminal or lead and cause current leakage or short circuits. This paper presents the results of an experimental study on tin whisker growth. Test specimens consisted of matte and bright tin finishes on copper, Alloy-42, and brass substrate materials. The heat treatments included annealing and two types of simulated reflow. Maximum whisker length and whisker density were measured on 24 different types of tin-plated specimens, after three, eight, and 16 months of room ambient storage after various heat treatments

Lead-free soldering in the Japanese electronics industry

The transition to lead-free electronics requires surmounting a host of technical, socio-political and economical issues. This paper discusses key concerns in lead-free product development, and provides guidelines to help equipment manufacturers efficiently implement a transition to lead-free electronics. The guidelines address key questions confronting the industry, including those related to lead-free compliance, lead-free part and supplier selection, lead-free manufacturing, and lead-free training and education.