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Ionic Contamination Tests

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GSx

#51901

Ionic Contamination Tests | 25 September, 2007

your comments will be appreciated, please;

IC tests have been performed on two kind of Raw PCBs (HASL) samples by adopting three different methods :

First Sample (supllier A)

- Omegameter 600 SMT, solvent=40�C: extratcing time 10 min result = 0.2 ugr NaCl/ cm2 (average)

- IPC-TM-650 2.3.25.1, solvent=80�C, extracting time 60 min result = 1.45 ugr NaCl/ cm2 (average)

- - IPC-TM-650 2.3.25.1, solvent=40�C,extracting time 60 min result = 0.62 ugr NaCl/ cm2 (avg)

Second sample (Supllier B)

Raw PCB (HASL)samples, have been tested by using same methods as above:

- Omegameter 600 SMT, solvent=40�C: extratcing time 10 min result = 1.4 ugr NaCl/ cm2 (avg)

- IPC-TM-650 2.3.25.1, solvent=80�C, extracting time 60 min result = 2.73 ugr NaCl/ cm2 (AVG)

- - IPC-TM-650 2.3.25.1, solvent=40�C,extracting time 60 min result = 1.67 ugr NaCl/ cm2 (AVG)

I am aware that by using different test methos, the results cannot be same, but I am interested to have your comments and suggestions in order to chose the most reliable Test Method to use. My opinion is that IPC-TM-650 2.3.25.1, solvent=80�C, extracting time 60 min, is more accurate but may be to "exagerate".

Thank you

Best Regards.....GSx

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#51902

Ionic Contamination Tests | 25 September, 2007

We vote for: IPC-TM-650 2.3.25.1, solvent: 80�C, extract time: 60 minutes, hold time: 30 minutes or until room temperature.

Listen, it really doesn't matter which method you decide to use. IPC-TM-650 2.3.25 is a process control method. It's more important that you: * Develop and maintain a consistent process. * Monitor your measurement results for changes that move you out of control. * Prevent the introduction of any additional ionic contaminants during the analysis process.

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#51926

Ionic Contamination Tests | 28 September, 2007

Just a shame that the HASL fluids that are used contain Hydrobromic or hydrochloric acids or a mixture of the two and are full of strong wetting agents that are NON IONIC so the IC test results mean very little as they are checking for Ionics only. PCB Extraction with IPA/DI at 80C followed by IR anaylsis works really well but since SCOPE Inc finished dont know who does it anymore. THIS is the one area that produces most reliability problems for this industry. Best of luck Cheers Greg York BLT Circuit Services Ltd

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#51939

Ionic Contamination Tests | 29 September, 2007

the vary results might be from following issues..

the co2 during the test

the during time for this testing...

the manual testing method is conductivity measurement however the bulk contamination tester like omega is resistance measurement (i remember) the latter one is less linear compared with conductivity measurment...

volume used for this measurement ...less volume means high concentration... even among any commercial instrument like omega the result varies...

the starting point ..water purity ....

omega is using spray for cleaning but manual method is immerse...

and so on...

so many different point between manual and bulk contamination tester...

basically contamination tester(ROSE) is more considered as the process monitor rather than lab analytical tool...

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