The driving forces for the fast development of lead-free solders ― especially in Europe ― can be categorized in three groups. First of all there is the regulation of the European Parlament for the restricted use of various dangerous materials in electronic devices. The background for this is to be seen in the health hazard impact of lead which affects the human body through the contamination of the ground water in the area of waste disposal sites. This health hazard obviously could not be proved indisputably as scientific studies ― especially from the US ― show. Despite these open questions, the commission of the European Community proposed the deadline for the lead-free substitution for January 1st, 2006 (issued: February 5th, 2001). On the other hand especially the applications of the automotive industry, telecommunications and mobile communication require higher operation temperatures which cannot be guaranteed with the presently used solders. The basic thoughts in this case are: product reliability, throughput, technological compatibility and other measurements which secure the process. It certainly has to be taken into consideration that in the meantime for years now, the automotive industry requests higher operating temperatures. Operating temperatures of 150°C or even 180°C are discussed. The target therefore is the development of solders, components with lead-free finishes, suitable printed circuit board material and the save process implementation, under consideration of the above mentioned temperature requirements for the permanent use. Another driving force for lead-free technology comes from Japan. It seems as if Japanese manufacturers use the "clean printed circuit board" as marketing instrument in order to achieve competitive advantages. This option - under the aspect of publications from Panasonic regarding an increase of turnover of 15 % for "green label" electronic products - obviously is not false. This background definitely leads to massive changes in the machine- and process technology of soldering systems like wave soldering, reflow soldering and selective soldering machines. This paper therefore shows the necessary machine modifications, like for instance surface structure alteration in case of wave soldering systems, the necessary energy supply mechanisms in case of reflow soldering systems as well as the special characteristics of the process related modifications.
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