In these cases the increase of the gas pressure caused a cooling down of the plume, which translated to in increase of sp2 content and crysterization of carbon atoms during flight. Taking into account the aforementioned examples, it seems that the double layering of films might be typical to reactive atmospheres. The fact that Budai et al. did not obtain double layers, despite using a similar methane-based deposition ambient, might be due to the different laser wavelength employed in their experiments. K. Yamamoto et al. studied the sp3 evolution function of laser wavelength for depositions conducted in vacuum, to exclude the background influence on films’ composition. They showed that sp3 content dropped from 80% when using 193 nm wavelength lasers (ArF) to about 40% when depositions were carried out with 248 nm wavelength (KrF). It is possible that the higher energy of the ablated carbon atoms allowed a higher mobility on the substrate and a better packing of the film.