Scanning tunneling microscopy investigation of carbon nitride thin films grown by microwave plasma chemical vapor deposition

The surface atomic structure of carbon nitride thin films deposited on both Si (100) and highly ordered pyrolytic graphite (HOPG) substrates by microw ave plasma chemical vapor deposition technique is studied by scanning tunne ling microscopy (STM), STM images of the surface of the films with atomic r esolution are obtained. The microstructure of the surface of the film on Si (100) substrate is very complex and composed of various components as conf irmed by other techniques. An atomic structure is observed in the complex s urface of the film on Si substrate. The unit cell constant of the structure is 4.7 Angstrom along a and b directions with 120 degrees angle between th em. This structure is clearly observed in the film deposited on HOPG substr ate at a larger scale. The structure is discussed. It is found that the obs erved structure is will in agreement with the G-C3N4 structure. (C) 1999 El sevier Science S.A. All rights reserved.