LA-ICP-MS, IC and DPASV-DPCSV determination of metallic impurities in solar-grade silicon

Stringent specifications are laid down for the silicon used for solar cells. The present work deals with the application of different techniques to the simultaneous determination of most common metallic impurities like iron, copper, nickel, zinc, lead and cadmium, in industrial process control. Laser ablation inductively coupled plasma mass spectrometry is quite expensive in apparatus, but it directly performs the analysis of solid silicon with very good sensitivity, even if coupled to considerable standard deviation, probably due to the material defects. Both ion chromatography and voltammetry need sample pre-treatment, but they are characterized by cheap and simple apparatus, suitable detection limits, good sensitivity and small standard deviation. (C) 1998 Elsevier Science B.V. All rights reserved.