The carbon films prepared from polyimide Kapton were investigated by X
PS and elemental analysis. The chemical states of carbon and nitrogen
gradually changed with carbonization temperature and the changes in th
e peak intensity ratio of I[N1s]/I[C1s] by XPS were consistent with N/
C mole ratios by elemental analysis. The N1s peak around 401 eV which
was a main component at 1200 degrees C was considered to correspond to
quaternary species such as a pyrrole type nitrogen. This species may
exist in the carbon films prepared at 2000 degrees C and affect their
properties. (C) 1997 Elsevier Science Ltd.