Has anyone heard of a no clean paste that can be cleaned in straight DI water ?

Thanks for the kind words Dave. At no point in my reply was I trying to sell anything. I apologize to anyone who believes otherwise. I agree with the poster, if assemblies are going to be cleaned, consider a flux designed to be cleaned. While this is good advise, there are many reasons assemblers give to reflow with no-clean flux, even if they are cleaning it. The primary reason I hear is the desire to run one common flux type and clean just the assemblies that require cleaning. This action adds efficiencies within the assembly process. Ironically, most fluxes cleaned today are "no-clean". This would make more sense if we referred to "no-clean" fluxes as "low residue" fluxes. The reality is many assemblies can tolerate low residues and do not require post-reflow cleaning. For those assemblies that are less residue tolerant, cleaning is an option.

Finally, contamination related ECM is not an overstatement. It is a reality which affects our industry. Unfortunately, carpenters see the world as a sea of nails and, perhaps, cleaning equipment and chemical manufacturers see the world as a sea of harmful residues. I am reminded, while I see this everyday, others do not. The reality is not every assembly requires cleaning. There are many assemblies that are highly reliable without the added step of cleaning. There are also others, without the removal of fabrication and assembly residues, may be subject to electro-technical migration issues including dendritic growth and parasitic leakage.

Ok... I will try to sneak away now without creating any more drama ;-)

Mike Konrad

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