Emission mechanism in polyimide

The fluorescence properties of pyromellitic dianhydride-oxydianiline (PDMA-ODA) polyimide are described. The quantum efficiency of fluorescence following excitation at 290 nm is measured to be 10-6. The spectroscopically parametrized (complete neglect of differential overlap) CNDO/S3 model is used to provide a quantitative description of the emission spectrum, and to make some preliminary conclusions about the mechanism responsible for laser etching of polyimides. © 1990.