Design for Cleaning in PCB Manufacturing

Q: Why can’t we just rely on “no-clean” fluxes instead of designing for cleanability?

A: Just because the flux is called a “no-clean” flux, doesn’t mean you should not clean it. There are plenty of published papers that prove “no-clean” fluxes under the right circumstances can still cause failures.

Q: What is the most cost-effective design change to improve cleanability without impacting performance?

A: It is all going to depend on the design, but getting rid of Silkscreen would be the easiest, because it is a layer you hide. Also, if you can space the components apart, that can be an easier change to make.

Q: How do we validate that our cleaning process is effective for complex assemblies?

A: You will need to work with your cleaner or testing facility to assure you do the correct testing, to qualify your cleaning process. This can include SIR Testing to make sure the boards are up to cleanliness standard.