Wavelength dependence on the formation of SiO₂ films by ultraviolet-laser-induced photochemical deposition using silicone rubber

We have proposed a novel method which permits to grow silicon dioxide (SiO₂) films on various substrates at room temperature using silicone rubber. In the method, two F₂ laser (157 nm) beams are used. One is used for generation of source gases from the silicone rubber (1st laser). Another is used for illumination of a substrate to deposit the films (2nd laser). We study on characteristics of the deposited films using laser beams which have longer wavelengths than the F₂ laser beam. When a fourth harmonics of Nd:YAG laser (266 nm) is used as the 1st laser, SiO₂ films with no carbon contaminants are grown as same as the case that an F₂ laser is used. The films are consisted of granular structures and the grain size become small as the laser fluence of 2nd laser beam increase. When an ArF laser (193 nm) is used as the 2nd laser, the deposition rate of the films is very low and the films have carbon contaminants. It shows that the 2nd laser beam plays an important role not only in the growth of the films but also in the prevention of carbon contaminants being mixed into the film.