DIAMOND DEPOSITION IN A MICROWAVE ELECTRODE DISCHARGE AT REDUCED PRESSURES

Diamond deposition on healed Si-substrates was studied under microwave discharge generated by an electrode-antenna either in a ''point-to-pl ane'' arrangement or in a ''parallel-plane'' arrangement at gas pressu res of 1-15 Torr in a mixture of hydrogen with methane and oxygen. Dia mond growth of 1 mu m h(-1) was obtained on surfaces ap to 2 cm in dia meter at microwave power of 150-200 W. No metal impurities from the el ectrode were detected in the diamond films. Typical gas mixture was 4% methane and 0.5% oxygen in hydrogen at a total pressure of 15 Torr. T he role of additional r.f, potential during the film deposition was st udied in the case of ''point-to-plane'' electrode arrangement. Correla tion of the power absorbed in the plasma and the optical emission of H atoms have been observed. (C) 1997 Elsevier Science S.A.