THESIS
1994
ix, 81 leaves : ill. ; 30 cm
Abstract
Chemical vapor deposition (CVD) of diamond films on silicon and on various other substrates from a methane/hydrogen mixture, as well as from other gas compositions has been reported and documented in the literature, using plasma, hot fiIament or acetylene torch as means of generating active species. Although the attempt to produce diamond films from polymers is not new, so far no crystalline diamond structures have been obtained, but only diamond-like carbon (DLC) has been reported....[
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Chemical vapor deposition (CVD) of diamond films on silicon and on various other substrates from a methane/hydrogen mixture, as well as from other gas compositions has been reported and documented in the literature, using plasma, hot fiIament or acetylene torch as means of generating active species. Although the attempt to produce diamond films from polymers is not new, so far no crystalline diamond structures have been obtained, but only diamond-like carbon (DLC) has been reported.
This technique employes laser ablation of polymers and the formation of crystalline diamond is described in detail. The results have been examined by Micro-Raman spectroscopy, X-ray photoelectron spectroscopy (XPS). secondary ion mass spectroscopy (SIMS) and scanning eIectron microscopy (SEM) as well as atomic force microscopy (AFM). The Raman peak at 1330 cm
-1 clearly identifies diamond, but its shape also reveals the presence of graphite. The peaks at 1350 cm[to the power of negative one] and 1597 cm
-1 identify gIassy carbon. SEM and AFM micrographs reveal the crystalline structure. Cubic blocks are formed as well as gains with about 1 μm size showing all the typical facets reported for diamonds. XPS valence band studies were used to investigate the degree of sp[superscritp 3] hybridization. SIMS was used to determine properties of the target polymer. It was found that graphitization and depolymerization take place at a very early stage due to heat accumulation,
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