Issue link: https://iconnect007.uberflip.com/i/831357
16 SMT Magazine • June 2017 take a hard look with an automated approach and not have to rely as heavily on the human inspector. That's because 3D has opened up the ability to at least be able to rationalize and ren- der views of what these 3D soldered joints really look like in real life. That is a major win for the EMS guys because now, we can have more test coverage and have more visual coverage, which gives us a higher degree of confidence that our product has no escapes. When I say no escapes, that there's any product that's not 100% com- pliant to the IPC standards or to the customer's expectation and his standards for acceptability." Are they looking at more in-line processes and inspection as well in their strategy? Yes, McMeen said. "I think Jean-Marc made a very good point. If we can tie in our SPI data off a Koh Young SPI machine, with the data from it being tied to the AOI data, now you're starting to get a better data set of information to judge how well your process is being controlled. Let me take just a minute and explain. If I have a SPI machine that's looking at my solder paste and I see any variability in it, I can take an AOI machine and look at the placement accuracy before I put it through reflow. It's not just the SPI variability. It's also the placement accuracy of the part onto the paste before you hit reflow. Then run it through reflow and run it through another AOI, which in this case would be the 3D AOI, to look at the quality of the solder joint that's been produced." "Now for the first time, I can quantify and see my variability of SPI on the board that is in question, to the placement accuracy on that solder paste to that SPI data, to what does my solder joint integrity and reliability look like based on the placement of the part and what the solder paste looked like right after it went through the screen printer. This is the first time that EMS guys can now have a total view of what that reliability and repeatability looks like from the print through the placement to the reflow and to the actual product," McMeen ex - plained. "By taking this data and analyzing it in a big data file, big data analytics, now you have the ability to really drive some improve- ments or tweaking to the stencil, to your place- ment accuracy, and ultimately to your reflow. We want to also tie in, at STI, the ability of gathering the reflow data and tying it back in at the time to the solder paste, the placement accuracy, and then the final 3D AOI of the sol - derability joint itself, the reliability and the vi- sual of that joint." Overall, the investment that companies put into their equipment and their testing param- eters will ultimately lower their total operating costs and improve their product delivery. "That is the correct assumption," said Mc- Meen. "All of this data is to make us make high- er first pass yields and to gather the data that's really meaningful to what's driving the issue. Instead of making decisions based on just the backend, now you're starting to look at what the in-process data looks like. Here's what the screen print and the solder paste looks like, how accurate the placement accuracy was based on skew of the placement of the part, what the re- flow looks like and, ultimately, what the 3D AOI visualizes and recognizes as a good solder joint. How are they consolidating all of this infor- mation, and analyzing and interpreting it? The cloud, according to McMeen. "Right now, we're trying to gather and make our equipment smarter, thus we are putting it into a cloud. That way, we're tracing it back to the original serial number of that particular as- sembly that we're building. Now, we're start- ing to see what the assembly yielded on a first pass yield or what the 3D AOI results found, and what the 2D found. The 2D is what we use now for our placement accuracy and then on to what the SPI data shows us. If you can gather that data and tie it back to that assembly num- ber, you now have a lot of data tied to that actu- al serialized number and now you're starting to make better decisions." 3D: TOWARDS BETTER INSPECTION CAPABILITY " It's not just the SPI variability. It's also the placement accuracy of the part onto the paste before you hit reflow. "