Ester-type precursor of polyimide and photosensitivity

In order to investigate the influence of the main chain structure and molec ular weight on the sensitivity of photosensitive ester-type precursor of po lyimide (photo-PAE), an improved method was used to synthesize several kind s of photo-PAEs with relatively high molecular weight. Their sensitivities (at 365 nm) were investigated, and it was found that some additives such as sensitizer and photoinitiator had the greatest influence on the sensitivit y of photo-PAE, that the photo-PAE with BPDA and mPDA as the main chain str ucture had the best sensitivity (D-0.5: 5-10 mJ/cm(2)) among the studied ph oto-PAEs, and that the sensitivity did not significantly change with the ch ange of inherent viscosity of photo-PAE. Meanwhile, the thermal imidization of these photo-PAEs was also investigated by means of TGA and IR analyses. Additionally, a discussion was made for formulation of PSPI resist. (C) 19 99 Elsevier Science Ltd. All rights reserved.