INPLANE ORIENTATION AND GRAPHITIZABILITY OF POLYIMIDE FILMS .2. FILM THICKNESS DEPENDENCE

The relation between the in-plane orientation of polyimide film and gr aphitizability was investigated. The degree of in-plane orientation wa s estimated by means of optical birefringence and ESR technique. The p olyimide film was found to have non-uniform orientation in the thickne ss direction because the thinner the film was, the greater the orienta tion. The inhomogeneity of orientation caused multiphase graphitizatio n in a film with a composite profile of the X-ray diffraction peak.