The effect of Ar⁺ ion bombardment on SiO₂ aerogel film

Ar⁺ ion bombardment on SiO₂ aerogel films was introduced to investigate the physical collision effect of oxygen plasma treatment on the films. The changes of internal surface adsorbing species and microstructure in the films were analyzed through the treatments. Through chemically inert Ar⁺ ion bombarding treatment, internal surface organic groups were partially removed. A slight increase in surface particle size was observed, which results from the condensation of SiO₂ particles due to the elimination of internal surface adsorbing organics. According to the increase in the accelerating voltage of Ar⁺ ion, the reduction of film thickness became larger than that observed with oxygen plasma treatment. The film thickness is maintained uniform with varying the treatment time and this confirms that there is no measurable etching happened within our treatment conditions. From these it is confirmed that a collapse of 3-dimensional network structure of SiO₂ aerogel film was happened though Ar⁺ ion bombarding treatment.