ISSN:
1433-0768
Keywords:
Key words Thermochemical polishing
;
Diamond films
;
Non-diamond phases
;
Defects
;
Atomic force microscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Polycrystalline chemical vapor deposition (CVD) diamonds films grown on silicon substrates using the microwave-enhanced CVD technique were polished using the thermochemical polishing method. The surface morphology of the samples was determined by optical and scanning electron microscopes before and after polishing. The average surface roughness of the as-grown films determined by the stylus profilometer yielded 25 μm on the growth side and about 7 μm on the substrate side. These figures were almost uniform for all the samples investigated. Atom force microscopic measurements performed on the surface to determine the average surface roughness showed that thermochemical polishing at temperatures between 700 °C and 900 °C reduced the roughness to about 2.2 nm on both the substrate and growth sides of the films. Measurements done at intermittent stages of polishing using confocal micro-Raman spectroscopy showed that thermochemical polishing is accompanied by the establishment of non-diamond carbon phases at 1353 cm−1 and 1453 cm−1 at the initial stage of polishing and 1580 cm−1 at the intermediate stage of polishing. The non-diamond phases vanish after final fine polishing at moderate temperatures and pressures. Photoluminescence of defect centers determined by an Ar+ laser (λlexct= 514.532 nm) showed that nitrogen-related centers with two zero-phonon lines at 2.156 eV and 1.945 eV and a silicon-related center with a zero-phonon line at 1.681 eV are the only detectable defects in the samples.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s100089900099
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