Surface reaction of a low-flux atomic oxygen beam with a spin-coated polyimide film: Synergetic effect of atomic oxygen and ultraviolet exposures

In-situ erosion rate measurement, residual gas analysis and surface charact erization of polyimide films exposed to an energetic atomic oxygen beam wer e studied. The polyimide films were formed on quartz crystals in order to m easure the mass loss rate with a quartz crystal microbalance during atomic oxygen beam exposure. The simultaneous exposure of a 5 eV atomic oxygen bea m and ultraviolet light provided a good correlation with the Right data reg arding the reaction efficiency of Kapton-H. The results of X-ray photoelect ron spectroscopy and Fourier transform infrared spectroscopy indicated that the PMDA structure in the polyimide was mainly degradated due to the atomi c oxygen exposure. The enhancement of carbon dioxide formation during the s imultaneous ultraviolet irradiation was clearly observed. This synergetic e ffect can be explained by the photochemical reaction of the carbonyl group under the presence of atomic oxygen.