IR laser induced CVD of SiO2 phases from triethoxysilane and tetraethoxysilane

CO2 laser induced decomposition of triethoxysilane and tetraethoxysilane in the gas phase affords a number of gaseous products and SiO2 films that incorporate all the silicon from the parent compounds. The process has been examined in batch and flow reactors at different temperatures of substrates to assess its potential for CVD of SiO2. FTIR and XPS analysis of the films reveals a small contamination by H and C, which decreases with increasing substrate temperature. The occurrence of elemental silicon in the SiO2 films produced from triethoxysilane reflects a hitherto unobserved mode of Si formation.