Electric Characteristics of Diamond Film Synthesized by Combustion Flame

The purpose of this research was to clarify the electric characteristics of diamond film synthesized by combustion flame and to synthesize a suitable diamond film for use in electroric device applications. When the film contains amorphous carbon, the dielectric loss increases, i.e., the electric characteristics of the diamond film become worse. To decrease the amorphous carbon in the diamond film we utilized three methods, the detection of the optimal equivalence ratio, the addition of hydrogen into synthesizing gas and heat treatment (annealing) of the diamond film. All of these methods can decrease the amount of amorphous carbon effectively, thus systematically changing the factors influencing the optimal synthesis for improving the film's electric characteristics. We have successfully developed a method for making high-quality diamond film with excellent electric characteristics, which has no dielectric loss in the wide frequency rage (102-108 Hz).