Homoepitaxial growth of high quality (111)-oriented single crystalline diamond

Different deposition parameters, for the growth of (111)-oriented single crystalline diamond samples were varied, such as temperature, methane concentration, methane/oxygen ratio and chamber pressure. It was shown that good quality material can be deposited at low methane concentrations with oxygen addition at high temperatures. Therefore, a growth temperature of 850 °C is used along with a pressure of 200 mbar, a CH4/O2 ratio of 3 and a methane concentration of 0.3% in order to prevent the incorporation of silicon in the single crystal diamond. Diamond layers with a thickness of 100 nm and 300 μm show RMS roughness values of around 0.26 nm and 200 nm, respectively.