Determination of trace impurities in silicon and chlorosilanes by inductively coupled plasma atomic emission spectrometry and neutron activation analysis

Abstract

Methods are described for the determination of trace elements in Si and chlorosilanes by inductively coupled plasma atomic emission spectrometry (ICP-AES) and neutron activation analysis. The chlorosilanes were hydrolysed and Si was removed as SiF₄ by evaporation of an HF solution. The dependence of the ICP signal on several parameters was studied and the operating conditions were optimised. For the chlorosilane matrix the Si was removed by evaporation. Radiotracers were used to measure the recovery of the elements of interest following the established procedure for sample analysis. The reliability of the proposed methods was checked using the National Institute of Standards and Technology (formerly National Bureau of Standards) Standard Reference Material 57 Refined Silicon. The methods were applied to the determination of trace impurities in various Si-containing materials.