I would say that the cleanliness requirements after rework would be the same as those imposed by the user as part of the initial requirements. IPC J-STD-001 Section 8.3.2 would cover the specific requirements unless the user has specified something different.
Kevin Mobley
PCBA Engineering Liaison, General Atomics Electromagnetic Systems Group
Kevin has over 30 years of experience in process and manufacturing engineering serving in both EMS and OEM companies. Expertise includes all aspects of SMT as well as wave solder and CCA materials such as PCBs, solder material, and component finishes. Kevin has developed processes for thousands of assemblies from stencil printing to conformal coating and testing.
The dedicate standard to BGA processes is the IPC 7095. Its important understand the full process and take in considerations all the variables and try to reproduce at moment of repair and rework to get the best result and
meet the standard criteria IPC-610.
The IPC-7095 standard internally call to IPC 7711 & 7721 to techniques repair and rework and IPC-610 to acceptance. The cleanliness criteria are a little bit ambiguous, because is focused only on visual inspection.
My recommendation is meet all the IPC standard statements and recommendations for process, rework, repair and visual acceptance. In my experience one of the most important think, is the materials selection (flux, solder, solvents, wipes , tooling etc.) this need to be fiber and dust free, halide free, low halide or zero halide to minimize the reliability issues.
Andres Rojas
Engineering Director / Master IPC Trainer (MIT), AMMSA Solutions
More than 20 years of technical experience in the electronics industry in roles ranging from Process & Project Engineer to engineering manager and Technical Applications Engineer for Latin Americas. IPC Master Trainer, International speaker and consultant.
IPC/EIA J-Std-001 "Requirements for Soldered Electrical and Electronic Assemblies" section 8, "Cleanliness Requirements" address these post soldering cleaning which I think it safe to assume applies to all post solder cleaning whether post-reflow/wave soldering or post-rework soldering and also regardless of the component type.
Paul Austen
Senior Project Engineer, Electronic Controls Design Inc
Paul has been with Electronic Controls Design Inc. (ECD) in Milwaukie, Oregon for over 45 years as a Senior Project Engineer. He has seen and worked with the electronic manufacturing industry from many points of view, including: technician, engineer, manufacture, and customer. His focus has been the design and application of measurement tools used to improve manufacturing thermal processes as well as moisture sensitive component storage solutions.
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