Physical characteristics of the annealed/isolated-diamond film

The polycrystalline diamond films were deposited on the silicon substrate using a methane/hydrogen gas mixture in a microwave plasma-assisted chemical vapor deposition system. Prior to deposition, the silicon wafers were pretreated by a photoresist in which 0.1 μm powder is suspended. The isolated-diamond film was obtained by etching the backside of silicon wafer with KOH solution. From X-ray photoelectron spectroscopy analysis, the oxygenated phenomenon was detected for the as-deposited diamond film and increased for both surfaces of the isolated-diamond film after the back-etching process. A thick SiC (282.7 eV) and non-diamond components (285 eV) interface layer was found on the bottom surface of the isolated-diamond film. However, it was found that part of the interface layer (SiC and non-diamond components) was removed and the amorphous carbon (285.8 eV) was appeared for the bottom surface of the annealed/isolated-diamond film and the silicon signal was appeared for the top surface of the annealed/isolated-diamond film. It was also found that the oxygenated phenomenon increased considerably after the 800°C annealing process. However, from the Raman analysis, it was observed that the full width half maximum was changed from 5.0 to 4.6 cm−1 and from 6.0 to 5.4 cm−1 for the top and the bottom surfaces of the annealed/isolated-diamond film, respectively. It was concluded that the oxygenated phenomenon increased on both of the top and bottom surface layers of the annealed/isolated-diamond film. However, it was found that the oxygenated phenomenon did not degrade the film quality since the quality of the isolated-diamond film was improved after the high-temperature annealing process.