Synthesis and optical properties of EB induced refractive index lithography materials based on aliphatic polyimides

Yamashita, Takashi*; Ogawa, Mutsuki*; Koshikawa, Hiroshi; Maekawa, Yasunari

Journal of Photopolymer Science and Technology, 20(5), p.739 - 742, 2007/00

https://doi.org/10.2494/photopolymer.20.739

Electron beam (EB) induced refractive index change of several polyimide films, which are one of the most thermally stable polymers. Introducing aliphatic amine into polyimide makes the polymer transparent and colorless in the visible wavelength region due to restriction of charge transfer, as well as increase in the sensitivity to EB induced reaction. One of the aliphatic poyimide, PI(HPMDA/mix-DCHM), prepared from cyclohexane tetracarboxylic anhydride and bis(4-aminocyclohexyl)methane, change the refractive index as large as 10 for both TE and TM modes. Chemical reaction during the EB irradiation was also determined as EB induced aromatization occurred.