Investigation of plasma interaction with carbon impurities on SiO2- and Al2O3 surfaces by EPR-, Mass- and emission spectroscopy

Carbon impurities on highly disperse SiO₂ and Al₂O₃ are detected by their interaction with low pressure plasmas, with aid of mass-, emission- and epr-spectroscopic methods. The formation of surface defects on SiO₂ by plasma treatment is strongly influenced by these impurities. Some of these defects are caused by the impurities also. These effects depend on the time of plasma interaction and on plasma gas, where Ar, O₂, H₂ and CO plasmas are investigated. By H₂ plasma and the reaction products of the other mentioned above plasmas a partial hydrogenation of the carbon impurities is detected.