Determination of 15 Impurity Elements in High Purity Aluminum Nitride Powder by Inductively Coupled Plasma Mass Spectrometry with Microwave Digestion

A method for determination of the 15 impurity elements in high purity aluminum nitride powder by inductively coupled plasma mass spectrometry (ICP-MS) with microwave digestion was established. Nitric acid of 3 mL was added into 0.10 g of the sample and the sample was digested by microwave digestion procedure. After cooling, the volume of the sample solution was made up to 100 mL with water. The matrix effect was corrected by Cs internal standard method, and the contents of 15 impurity elements, including B, Mg, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Zr and Mo, were determined by ICP-MS. As shown by the results, the linear range of the standard curve of each element was 1.0-100.0 μg·L^-1, and the correlation coefficient of the standard curve of each element was not less than 0.999 0, with detection limits (3s) in the range of 0.02-0.07 μg·g^-1. Aluminum nitride samples were analyzed by the proposed method, with RSDs (n=7) of the determined value less than 5.0%. Test for recovery was made by standard addition method, giving values of recovery in the range of 88.0%-114%. Compared with inductively coupled plasma atomic emission spectroscopy (ICP-AES), the results obtained by the two methods were basically consistent.