Abstract:

The Diamond/ceramic composite was obtained from composite precursor by sintering. The composite precursor is prepared from gelatin by mixing the synthesized collosol，which will generate the ceramic phase，into diamond powder. The gelatin powder was characterized by DSC，FTIR，SEM，EDS and XRD after thermal treatment，which proves that the amount of the alkali metal added into composite material can be controllable by sol-gel method，and the dielectric loss can be ultimately reduced. The resistivity and dielectric property of the sheet-shaped composite is calculated within high frequency region by resonance circuit. It shows that the resistivity of diamond massive composite is slightly larger than that of diamond thin-film，with the dielectric loss less than 0.002，which is lower than that diamond thin-film of nanometer. The softening temperature is reduced greatly in sol-gel method and the addition of the alkaline metal can be controlled. The diamond composites with dielectric properties superior to that of diamond films are eventually obtained. The simple composite preparation method provides a great potential for mass manufacturing.