Phil, Very strange. Has the ROSE tester been calibrated? Physically what is different between one test sample and the other two? Were all three test samples ROSE tested together or separately? Were they shipped together or in separate bags or even in totally separate packages? How far away is your manufacturing facility from the lab? Next door? Next city? Next state? What are you getting for chloride readings for your blanks? Bev -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Phil Bavaro Sent: Monday, October 08, 2012 7:30 PM To: [log in to unmask] Subject: [TN] ION CHROMATOGRAPHY - EXCESS CHLORIDE CONTENT We have some results that have left me puzzled. We are processing the IPC B-52 test PWAs using water soluble paste/flux and we can pass the ROSE test (of course) and the SIR test, but fail the IC test for excessive choride anion content. Here is what baffles me.....our control sample is similar and worse than the test samples. There seems to be some documentation that the chloride ion might be related to mishandling and/or soldermask not being properly cured but I don't have any experience with this test result so I am not sure how to respond to that (hopefully Terry will chime in on this). We processed all the samples using the proper gloves and bags and doubt that we contaminated them. We are trying to meet the requirement of 0.9 micro-gm/cm-cm maximum and our failing control sample is 3.36, one test sample is 4.67, and the other two samples are running at .91 and .90. What value for chloride anion content does a normal WS process yield? Are these numbers way out of range for normal test results or is chloride always a pesky result? I am looking for the answer to the question "is this really a problem?" The control sample was washed but did not have any paste applied to it at all. The test samples were run through the full assembly reflow process then cleaned and Rose tested before shipment to the lab. All the rest of the results for the IC test are passing so I don't know quite how to proceed from here. My current plan is to run another set of tests with more than one control sample, and then to simulate various phases of clean (IOW barely cleaned, half cleaned, and then a couple of fully cleaned samples). As I am not really familiar with IC test results, I want to see the what the constituents of the "dirt" really look like from an IC test perspective as well as repeat the previous test results. One item I have noted is that we did not have our chosen board supplier build these boards but instead bought these off the shelf from one of the dummy component suppliers. But the thought was that as long as they were cleaned using our normal process, they should be acceptable. These particular test samples use FR4 and not the high Tg polyimide that most of our PWBs are built from. Any comments on this would be appreciated. ---------------------------------------------------------------------------- -- This message and any attachments are solely for the use of the addressee and may contain L-3 proprietary information that may also be defined as USG export controlled technical data. If you are not the intended recipient, any disclosure, use or distribution of its content is prohibited. Please notify the sender by reply e-mail and immediately delete this message and any attachments. ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________