DETERMINATION OF TRACE IMPURITIES IN POWDERED MOLYBDENUM METAL AND MOLYBDENUM SILICIDE BY SOLID SAMPLING GFAAS

A direct atomic absorption spectrometric method for the determination of the elements Cu, K, Mg, Mn, Na and Zn in high purity molybdenum metal and molybdenum silicide powders for microelectronic applications was developed. By using a cup and boat solid sampling technique, the sample preparation step and the contamination risk were considerably reduced, so that these elements could be determined at concentrations down to the sub-ng/g level in a few minutes. Using the maximum applicable sample portion of 80 mg for molybdenum and of 10 mg for molybdenum silicide, limits of detection in the range 0.06 (for Zn)-0.5 ng/g (for Na) and 0.5-4.5 ng/g, respectively, were achieved for the six elements with the boat technique.