Determination of iron in semiconductor-grade silicon by furnace atomic-absorption spectrometry
Abstract
The determination of iron in semiconductor-grade silicon for device production by furnace atomic-absorption spectrometry is described for iron contents down to a level of 5 ng gā1 in slice and polycrystalline material. The silicon matrix is first removed by treatment with hydrofluoric acid - nitric acid. Reagent purification and the selection of the most suitable furnace materials have been studied. Surface iron contamination is assessed separately by a chemical etching technique.