Synchrotron radiation-excited etching of SiO2 with SF6 at 143 and 251 Å using undulator radiation

Photoexcited etching of SiO2 surface with SF6 gas is studied using undulator radiation at 143 and 251 Å as an extreme ultraviolet light source. The SF6 pressure and the wavelength dependences of the etch rates have been measured for SiO2 in the pressure region between 0.016 and 0.50 Torr. We find that, at these wavelengths, the etch rate is proportional to the intensity of the light absorbed by the surface species, most probably SiO2 in the pressure region studied.