Formation of carbon nano-flakes by RF magnetron sputtering method

Abstract

Carbon nano-flakes were formed on Si(001) surface by rf-magnetron sputtering. A graphite plate was used as the sputtering target. Ar-methane mixture gas was introduced into the sputtering chamber as the discharge gas. The structure of the sputter deposited samples was investigated by field emission type scanning electron microscope, high resolution transmission electron microscope and electron diffraction method. Carbon nano-flakes were observed on the Si substrate after a few minute sputter deposition. No other allotropes such as nano-tubes, soots, nano-fibers and nano-horns were observed. The flakes were found to be graphite sheets and to grow to the plane direction with increasing time. The length of the flake seemed to increase approximately proportionally to the sputter deposition time, while the thickness increase was very small. The formation process of the flake was discussed considering the adsorption and desorption process of carbon atoms on graphite surface.