Uniform carbon nanoflake films and their field emissions

Films of uniformly distributed carbon nanoflakes have been prepared by using hot filament chemical vapor deposition. A large amount of carbon flakes with a thickness of less than 20 nm interlaced together to form a layer of carbon nest-like film with their sharp edges almost perpendicular to the Si substrate. Raman spectroscopy showed that the films were characteristic of pyrolytic graphite and became more disordered with the increase of substrate temperature and acetylene concentration. The growth mechanism of the carbon nanoflake films was discussed. The field emission performance has been done, showing a turn-on field of about 17 V/mum. Considering the ease of large-area preparation, the carbon nanoflake films might have a potential application in vacuum electronic devices, (C) 2002 Elsevier Science B.V. All rights reserved.