Laser - induced modification of hydrogenated amorphous carbon films

Abstract

Laser-induced modification of thin films of amorphous carbon (a-C:H) was investigated. The films have been deposited by DC PECVD on silicon substrates using different bias voltages: 1 kV, 1.5 kV, 2 kV, and 2.5 kV. Raman spectra of the films measured in a micro-Raman system at 633 nm with different laser power were recorded. It was observed an increased D-peak for laser power density of 1010 W/m2 indicating modification of the film by the laser, which does not happened for smaller laser power. This modification is stronger in the films produced at higher bias voltages, which have stronger absorption at 633 nm. This observation suggests that laser modification of a-C:H films is due to thermal effects.