A test vehicle and qualification test for proving out process changes.
IPC J-STDF-001G states, “Unless otherwise specified by the User, the Manufacturer shall [N1D2D3] qualify soldering and/or cleaning processes that result in acceptable levels of flux and other residues. Objective evidence shall [N1D2D3] be available for review.”1 (Ed.: N1D2D3 means no requirement has been established for Class 1, and the condition is a defect in Classes 2 and 3.)
In a qualified manufacturing process (QMP), manufacturing materials and processes used to produce electronics hardware are benchmarked and validated against electrical performance in hot/humid conditions.2 Characterizing chemical residues that exist on a manufactured assembly, and assessing the impact of those residues on electrical performance, has much to do with the end-use environment in which the hardware will operate. The other important factor is the circuit density and component types. Leadless and bottom-terminated components are more susceptible to residue challenges due to low standoff gaps, tight pitch, high solder mass, and blocked outgassing channels.
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