Ionic and atomic absorption spectroscopic study of magnesium ionization in cathodic sputtering glow discharge plasma

Abstract

Ionic and atomic absorption spectrometries were used to study magnesium ionization in cathodic sputtering glow discharge (CSGD) plasma with aluminum–magnesium alloys as cathodes. A method, based on Doppler broadening-dependent absorption width, of ionization degree resolution by relative absorbance is proposed. The experimental results reveal that there are plentiful magnesium ions in the plasma under the conventional discharge conditions of the atomizer. The matrix element aluminum shows preferential ionization and restricts that of magnesium. Also magnesium ionization degree increases with the discharge power but decreases with the distance from the cathode.