Raman Studies of Amorphous Carbon Phase in Diamond Films Grown by Hot-Filament CVD

Abstract

Microcrystalline diamond thin films have been prepared using hot filament CVD technique with a mixture of H2/ CH3OH as the reactant gas. We demonstrated that the ratio of H2/ CH3OH in the reactant gas and total pressure in reactor chamber plays an important role in control of the grain size of diamonds and the growth of the microcrystalline diamonds. The object of this article is to summarize and discuss relation between structural properties of different diamond layers and technological parameters of their synthesis. The physical properties of the Hot Filament CVD microcrystalline diamond films are analyzed by Scanning Electron Microscopy and Raman spectroscopy. The sample grain size varies from 200 nm to 10 μm and their quality was checked on basis of 1332 cm−1diamond peak. The ratio of sp3/sp2carbon bonds was determined by 1550 cm−1G band and 1350 cm-1D band in the Raman spectrum