DETERMINATION OF ULTRATRACE AMOUNTS OF METALLIC AND CHLORIDE-ION IMPURITIES IN ORGANIC MATERIALS FOR MICROELECTRONICS DEVICES AFTER A MICROWAVE DIGESTION METHOD

A digestion method was developed for the determination of ultratrace c oncentrations of sodium, potassium, magnesium, calcium and chloride io ns, Using ETAAS and ion chromatography, the digestion method was appli ed successfully to the determination of ultratrace concentrations of t hese elements in organic materials for microelectronics devices such a s photoresists, epoxy resins, and liquid crystals, Very low contaminat ion levels were maintained throughout the procedure, The blank levels were 0.05 ng for sodium, 0.02 ng for potassium, 0.03 ng for magnesium and calcium, and 20 ng for chloride ion, The method is very effective in measuring the impurity distributions of organic materials whilst pr eventing their contamination from the surrounding environment and from the reagents used in the procedure.