More recently environmental legislation has specifically targeted the wide use of lead in the electronics industry. The ROHS directives in Europe require many new electronic circuit boards to be lead free by 1st July 2006, mostly in the consumer goods industry, but in some others as well. Many new technical challenges have arisen with this endeavour.
For instance, traditional lead-free solders have a significantly higher melting point than lead-based solders, which renders them unsuitable for use with heat-sensitive electronic components and their plastic packaging. To overcome this problem, solder alloys with a high silver content and no lead have been developed with a melting point slightly lower than traditional solders.
Lead-free construction has also extended to components, pins, and connectors. Most of these pins used copper frames, and either lead, tin, gold or other finishes. Tin finishes are the most popular of lead-free finishes. Nevertheless, this brings up the issue of how to deal with tin whiskers. Somehow, the current movement brings the electronics industry back to the problems solved in the 1960s by adding lead.jedec has created a classification system to help lead-free electronic manufacturers decide what kind of provisions they want to take against whiskers, depending upon their application creaticity.
