Reliability Design for Manufacturability
When looking at the manufacturing of electronic products and the use of lead-free solders, there are some issues that have to be considered. Issues such as alloy selection and paste handling, component type and component finishes, fluxes, and manufacturing process parameters, such as temperature, time, and atmosphere, have to be reevaluated when changing to lead-free solder manufacturing.
Lead-free solders present different physical properties compared with the conventional tin–lead solders. The most accepted lead-free alternatives present, for example, higher melting temperatures compared with the typically used Sn–Pb eutectic solder, which can affect both the manufacturability and reliability of lead-free electronics. Smaller process windows, damage to temperature sensitive components, and board warpage are only some examples of the problems that can occur while soldering with lead-free solders.
This chapter gives a short introduction to such issues, from the effect of higher processing temperature, failures resulting thereby, other defects connected to the fact that lead-free solders present different physical properties, inspection issues, repair, and rework of lead-free products. Other issues, such as lead contamination and tin whiskers are also shortly presented and discussed.
KeywordsSolder Joint Solder Alloy Whisker Growth Lead Solder Wave Soldering Process
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