J. Phys. IV France 05 (1995) C5-989-C5-995
Diamond Deposition Using a Grid FilamentD.M. Li1, T. Mäntylä1 and J. Levoska2
1 Institute of Materials Science, Tampere University of Technology, P.O. Box 589, 33101 Tampere, Finland
2 Microelectronics and Material Physics Luboratories, University of Oulu, P.O. Box 400, 90571 Oulu, Finland
A grid tantalum filament of a dimension of 3 x 4 cm2 was used for diamond synthesis by hotfilament assisted chemical vapour deposition (HFCVD). After proper carburization, the filament could be used for multi-cycles of deposition. By heating the filament to 2400°C in 8% CH4 mixed with H2, diamond has been deposited at rate of about 5 µm/hour on (100) oriented silicon substrate placed 5 mm away from the filament. By X-ray diffraction (XRD), the structure of the films deposited in the mixture of CH4 and H2 was characterized as diamond, while tantalum oxide was found in the presence of oxygen during deposition. The deposited diamond appeared uniform over an area of 2 x 3 cm2 observed by scanning electron microscopy (SEM) perhaps due to the stable filament geometry. Raman spectra of these films showed a sharp peak near 1332 cm-l, which indicated the presence of a large amount of sp3 bonds in the film. The present grid filament can be scaled-up for large area diamond deposition.
© EDP Sciences 1995