USE OF SPUTTERING AND NEGATIVE CARBON ION SOURCES TO PREPARE CARBON NITRIDE FILMS

Carbon nitride may have many different uses as wear and corrosion resi stant coatings, electrical insulators, and optical coatings. We report the results of using sputtering and negative carbon ion sources to pr epare thin films of carbon nitride. In this work, we compare the tribo logical properties of the carbon nitride films that were prepared by t wo separate ion-beam assisted techniques. The first approach used an O NYX-2 magnetron to sputter deposit carbon in a nitrogen atmosphere wit h and without simultaneous bombardment of the growing film with low-en ergy (similar to 50-200 eV) nitrogen ions. The second method utilized a beam of negatively charged carbon ions of 1-5 mA/cm(2) current densi ty impinging the substrate at the same time with a positive nitrogen i on beam produced by an ''Ion Tech'' Kaufman source. We were able to pr oduce microscopically smooth, continuous coatings that are harder than silicon. These films possess wear rates lower than 5 X 10(-7) mm(3)/N m and friction coefficients in the range of 0.16-0.6. These data compa re favorably with the results obtained by other authors. Raman spectro scopy revealed that the magnetron sputtered films are more structurall y disordered than those formed with the negative carbon ion gun. Fouri er transform infrared spectroscopy showed the presence of C drop N str etching mode in both types of films. (C) 1997 American Vacuum Society.