The synthesis of carbon nitride thin films with high nitrgen concentration was accomplished by reactive supttering at relatively high working pressure. In conventional reactive sputter-deposition of carbon nitride films, working pressure was 0.3-5Pa and the ratio of nitrogen to carbon(N/C ratio) in the films was less than 0.5. In this study, amorphous carbon nitride films with the N/C ratio $ ickapprox$ 1.0 were prepared on Si(100). substrates at higher pressure, 20-60 Pa. Structural analyses with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the films prepared consisted of triazine-like plain network.