NEXAFS study of DLC films prepared by Ar cluster and monomer ion assisted deposition

Abstract

Diamond Like Carbon (DLC) films were formed by Ar cluster ion beam assisted vapor deposition of C60. To study the effects of contaminating Ar monomer ions (Ar) in the cluster beam on the sp2 content, film hardness, and surface morphology of the films, beams of Ar cluster ions, Ar+, and a mixture of cluster ions and Ar+ were used for the bombardment, during evaporation of C60. From the Near Edge X-ray Absorption Fine Structure (NEXAFS) and Raman spectroscopy measurements, lower sp2 contents in carbon films were obtained for the cases when Ar cluster ion beams were used. The usage of single Ar+ and mixed ion beams showed higher sp2 contents. Furthermore, higher hardness and smoother surfaces were obtained with Ar cluster ion irradiations. Therefore, the increase of the fraction of Ar cluster ions in the beams was important to obtain hard DLC films with flat surfaces.