Cleanliness testing of Printed Circuit Boards
The test procedure is based on IPC-TM 650, Test Method 2.3.28,”Ionic Analysis of Circuit Boards, Ion Chromatography Method”.
The contaminants on each PCB assembly are extracted by placing the object in 0.3 ml/cm2 of highly purified water in a plastic bag of polyethylene, which is then hot pressed sealed. Contaminates on the printed circuit board are extracted by placing the bag in an ultrasonic bath at 60°C for 30 minutes. Highly purified MilliQ water is used and has a specific resistivity >18 Mohm·cm. A small volume of the extract solution is taken directly from the bag with a syringe and injected into the Dionex 300 ion chromatograph with AS 9 anion colon and ion suppressor.
The analysis comprises inorganic ions such as F-, Cl-, Br-, PO43-, SO42- and NO3-, and flux residues from dicarboxylic acids such as, adipic, succinic, glutaric acid and formate.
The results from the ion chromatography analysis are presented in a table with the concentration of the various contaminants in the extracted water in mg/l and the normalised surface cleanliness expressed as µg/cm2.
This service is offered to fixed prices to costumer.