Determination of eight impurity elements in industrial silicon by inductively coupled plasma atomic emission spectrometry

The inert sample injection system resistant hydrofluoric acid of inductively coupled plasma atomic emission spectrometer was used.The sample solution was injected directly without removing hydrofluoric acid and silicon matrix after sample was dissolved in hydrofluoric acid,nitric acid and perchloric acid.Eight impurities including iron,aluminum,calcium,titanium,manganese,nickel,boron and phosphorus in industrial silicon powder were simultaneously determined by inductively coupled plasma atomic emission spectrometry(ICP-AES).Most of matrix silicon had been volatilized and removed in sample dissolution process,so the matrix effect had no influence on the determination of iron,aluminum,calcium,titanium,manganese and nickel.However,the determination of boron and phosphorus was still affected,which could be eliminated by vertical observation method.The detection limit of the method was calculated by three times of standard deviation of blank.The detection limits(w/%) for iron,aluminum,calcium,titanium,manganese,nickel,boron and phosphorus were 0.004,0.001,0.004,0.001,0.0001,0.0001,0.000 04 and 0.000 06,respectively.The proposed method was applied to the determination of eight impurities in industrial silicon.The found results were consistent with the certified values or those obtained by standard method(GB/T 14849.4-2008).