Structure and optical properties of conglobate hydrogenated amorphous carbon films prepared by pulsed laser-induced chemical vapor deposition

The hydrogenated amorphous carbon films were prepared by pulsed laser-induced chemical vapor deposition at room temperature. In the proposed technique, the styrene with no catalyst was used as a carbon source. The conglobate microstructure of the films was observed. The influence of various laser repetition rates on the structure and optical properties of the films was investigated. With the increase of laser repetition rate, the films possessed more aromatic bonds, more sp3 carbon and less sp2 clustering. A broader optical band gap and lower photoluminescence intensity was simultaneously found. The results were attributed to the different distribution of electronic localization around the level edge with different laser repetition rates. Therefore, we can tune the structure and optical properties of the films according to change the laser repetition rates.