The role of H{sub 2}O in enhancing hot filament assisted diamond growth at low temperatures
- Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6093 (United States)
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996-1600 (United States)
The addition of a small amount of oxygen to a hot filament assisted chemical vapor deposition reactor allows diamond to be deposited at significantly lower filament and substrate temperatures. Scanning electron microscopy and Raman spectroscopy are used to compare films grown with and without oxygen addition as a function of substrate temperature at high and low filament temperatures. Oxygen addition is found to favor growth of high quality diamond at low substrate temperatures ({lt}600{degree}C). The amount of nondiamond carbon is reduced and the clarity and smoothness of facets improves dramatically under these conditions. Equilibrium calculations and residual gas analysis indicate there is H{sub 2}O in the gas above the substrate during these depositions. The correlation between the dramatic reduction in the nondiamond carbon content of the films and the increased H{sub 2}O levels near the substrate at low temperatures leads to the conclusion that H{sub 2}O plays an important role in facilitating deposition at lower temperatures. Potential roles for H{sub 2}O include terminating carbon dangling bonds by dissociative adsorption and enhancing selective etching of nondiamond carbon by O{sub 2}. The gas and surface chemistry of diamond deposition at low temperatures with oxygen addition is also discussed. {copyright} {ital 1997 American Institute of Physics.}
- Research Organization:
- Oak Ridge National Laboratory
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 450245
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 3 Vol. 81; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
HFCVD of diamond at low substrate and low filament temperatures
In situ Raman spectroscopy of diamond during growth in a hot filament reactor