Diamond-like carbon films deposited by laser ablation using frozen acetylene targets

A new laser ablation method based on frozen gas targets was tested by depositing carbon films. The source gas was acetylene. With an ArF laser at a power density of 9×108 W/cm2 the deposition rate varied from 17 nm/min at room temperature to 13 nm/min at a substrate temperature of 300 °C. The films showed the broad Raman peak at 1540 cm−1 characteristic of diamond-like carbon films. A KrF laser produced the diamond-like carbon films at substrate temperatures above 200 °C. Particles were absent in the films if the power density was not excessively high. Energetic species ejected from frozen acetylene improved the adherence of the films to quartz substrates.