Issue link: https://iconnect007.uberflip.com/i/1010078
16 SMT007 MAGAZINE I AUGUST 2018 cause because environments still play a role; how effective Operator A is versus Operator B, how old the cleaning brush is, things like that. There are a lot of little things that come into play to avoid failure when it comes to cleaning. Matties: When somebody has a need for high reliability, they just spec the cleaning process in, correct? Camden: More times than not, yes. Matties: For that very reason, you can never know that failures are going to happen, so it's an insurance policy. Camden: The biggest problem we see with that now is the cleaning of no-clean flux and how to properly address the risk. Again, when an engineer hears the words no-clean, they assume the risk is very low when their residues are left behind a f t e r t h e wa s h p r o c e s s — w h e n it is the opposite. In a nutshell, the residues left behind from an improper, ineffective wash p r o c e s s o n a no-clean flux can be as detrimental as water soluble flux left behind. Matties: So, if somebody wanted to really do an audit of their cleaning process, what are the steps that they should consider? Solis: They should use the proper metrics. How are they cleaning? How are they measuring that their boards are clean? What internal or external standards are they trying to achieve? Matties: I see that you do on-site offerings and classroom training. How many companies do take you up on that type of training at operator level? Camden: I would say that from a cleaning side of things, we probably do trainings about 15 times a year. We don't schedule the classes; we are very reactionary when it comes to that. And usually, when it comes down to onsite audits, they are a reaction to a failed process. I have a handful of companies that I go onsite for annually, just to look at their line, look at their wash, the entire assembly process, but that's the minority of the cases. The majority have field problems, so they will call us in. We'll do some ion chromatography, we will look at some boards that have failed. We'll look at not just their parameters, but their maintenance records, how they are doing everything they should be doing, if they are maintaining their cleaning equipment properly, and at the right intervals. So, there's really no answer to how often we do that year-to-year, but I would say that for the most part, it's reactionary because the company has done something wrong, and they ask us to come in, look at their process, and optimize it. Solis: We call that baptism by fire. Now, they have to try to put that into DFM, where they should be looking for opportunities for contamination introduction. And they are also rethinking what "optimized" means to their process, if they are really doing best practices, and if their process is really optimized. When we show up, we'll say "You didn't quite optimize those boards for this thermal mass. But if you do these couple of tweaks here, and you can validate in the lab, maybe you don't need to clean at all." That's always an option— if they are truly optimized for the no-clean, they may not even need to clean. Matties: In terms of cost and time, what impact does that have on the order? How much cost or time are we adding to that? I've had people tell me it's just pennies and it's just a quick process. Camden: Right. And we always like to compare Eric Camden, Foresite Inc.