To minimize the occurrences of solder robbing during reflow, the profile should be modified to have a longer low temperature soak time to drive off the lower boiling point volatiles.
Additionally, the boards could be reflowed in an inert atmosphere to preventany additional oxidation. The nitrogen level should be between 20 to 200 ppm of oxygen.
Terry Jeglum
President/CEO
Electronic Technology Corporation
Mr. Jeglum has 35+ years experience and is the founder of Electronic Technology Corporation. He is responsible for 22 years of program management for the Company.
Why do you believe it is related to temperature uniformity?
Typical drivers for solder robbing is overprinting or slump of the solder paste. Is this under a BGA?
Dr. Craig D. Hillman
CEO & Managing Partner
DfR Solutions
Dr. Hillman's specialties include best practices in Design for Reliability, strategies for transitioning to Pb-free, supplier qualification, passive component technology and printed board failure mechanisms.
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