QFN Rework Challenges in a Lead Free World IPC Midwest - Sept. 2007
It is clear that the future belongs to the ever shrinking component. Micro Lead Frame (MLF) components,and specifically the Quad Flat No-lead (QFN) packages have gained wide scale acceptance. They tend to appear in densely populated boards where real estate is at a premium.
The design,size and assembly process of QFN’s present some unique rework challenges not seen with other components. The challenge is only greater with the use of lead-free solders. This paper/presentation will focus on the complete rework process,including component removal,site preparation,component paste printing,and finally new component soldering.