Comparative study on infrared properties of PLD-grown DLC film and SiC film

Diamond-like carbon and silicon carbide coatings were grown by pulsed laser deposition under different laser fluences, and their infrared transmission spectra were compared with each other. Raman spectroscopies and their deconvolutions for the silicon carbide films prepared by different laser fluences exhibited no changes nearly in micro-structure, and the infrared spectra showed these layers had high infrared transmission. On the other hand, the obvious changes in micro-structure of the diamond-like carbon films grown by the different laser fluences, which indicated laser fluence played an important role in the growth process of the diamond-like carbon films. A relatively higher laser fluence could grow the diamond-like carbon film with higher sp3 bond content, increasing the infrared property, while a lower one increased the absorption of the layer, reducing its infrared transmission seriously. Nano-scratch test showed that silicon carbide layer can be used as the buffer layer for the multilayer diamond-like carbon film enhancing the adhesive performance of the whole coating on the substrate with the protective and anti-reflective properties.