Single composite target magnetron sputter deposition of crystalline and amorphous SiC thin films

Abstract

The formation of crystalline and amorphous SiC films by single-composite target magnetron sputter deposition process is demonstrated. In this process, graphite pieces were placed on a Si target to form a composite single target. The graphite coverage area (GCA) was varied between 4 to 18% to achieve controllable carbon content in the films with stoichiometry being achieved at ∼13% GCA. The films on Si substrates crystallized into the 21 H polytype of SiC, without any additional heating during deposition. However, SiC films deposited on quartz substrates under the same processing conditions are amorphous. These films show high transparency (greater than 80%) in the visible and near infrared regions with an optically measured band gap of 3.4 eV and refractive index of 1.96 at a wavelength of 1300 nm.