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Crystalization on TI QFP and other fine pitch components

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#63011

Crystalization on TI QFP and other fine pitch components | 28 October, 2010

We are having a little trouble with what appears to be a crystalization between our fine pitch parts. The problem appears after a a thourough wash of the pcb when dry. It looks like lead wiskers/haze between the joints.We are using water soluable leaded paste. The profile for the board is dead on and we always use new paste. Cleaning is not an issue as we use an inline cleaner and then a high pressure closed loop aqueous trident batch cleaner. This seems to happen to TI parts and Altera. Our only way to solve this is to tin the parts by hand. We are thinking it is an oxidation problem.

Anyone else having similar problems or have had in the past.

Thanks in advance

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