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
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