Highlights of a EC funded project on Lead-free Materials and Assembly Development Technology

The EC has financially supported a pan-European collaboration on the development of lead-free interconnection materials and use of these materials for electronic assembly in a wide variety of industrial applications. The project started in April 2002 and is now close to the end. For the lead-free interconnection materials the focus was on lead-free solders, as well as on adhesives. The materials were developed by Heraeus, Germany. The developed solders and adhesives were used in following industrial sectors : displays (Tecdis Iberica, Spain), automotive (Fiat, Italy), telecom systems (Alcatel, Belgium), smart cards / smart labels (KSW Microtec, Germany) and portable telecom (Elcoteq, Finland). Conventional passive components, as well as more sophisticated ones like BGA's or CSP's were assembled. Special emphasis was on flip-chip assembly. For this purpose dedicated test chips were designed and fabricated (AMIS, Belgium). Industrial partners were assisted in their technology developments by two research institutes : TUBerlin, Germany, and IMEC, Belgium. TUBerlin also developed lead-free solder wafer bumping technologies, while IMEC performed mechanical and thermal-mechanical modelling activities. IMEC also served as the co-ordinator of the project. In this introductory talk the IMECAT project objectives and main realisations will be highlighted.The paper/presentation will contain a summary of main results extracted from following project topics: - Development of a Lead-free Solder Paste (Heraeus) - Technological Advancements in Lead-free Wafer Bumping using Stencil Printing Technology (TUBerlin) - Lead-free Flip Chip: a comparison between lead-free solder and adhesives (IMEC) - Thermo-Mechanical FEM Analysis of Lead Free and Lead Containing Solder for Flip Chip Applications (IMEC) - Lead-free soldering development for assembly of complex telecom boards (Alcatel Bell) - Lead-free Electronic Assembly for Automotive Applications (CRF) - Development of the lead free soldering process for portable applications (Elcoteq)