An XPS and glancing angle RBS investigation of metallic impurity contamination of magnetron sputter etched Si

A semi-quantitative analysis of metallic impurity contamination of magnetron sputter etched Si is presented using X-ray photoelectron spectroscopy and glancing angle Rutherford backscattering spectroscopy. Impurity contamination increases, whereas Ar incorporation and damage created in the near-surface region of etched samples decrease with increasing plasma pressure. Chemical cleaning could adequately remove metallic impurities from a surface etched at the highest plasma pressure. Increasing the substrate bias also results in an increase in metallic contamination, and a decrease in Ar incorporation. However, structural damage increases up to ∼400 V, and thereafter decreases. The electrical properties of Pd/n-Si Schottky diodes fabricated on sputter etched samples show that metallic impurities does not affect the extent of their barrier height modification.