| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polyimide precursor manifesting excellent photosensitive characteristics, providing a high resolution, excellent in remaining rate of a membrane, good in volatility at the time of imidation and characteristics of hardened membrane, and useful for a surface-protecting membrane or the like of a semiconductor by including a specific repeating unit. SOLUTION: This polyimide precursor contains a repeating unit of formula I [Ar1 is a tetravalent organic group having an aromatic ring; Ar2,, is a divalent organic group having an aromatic ring; X and X' are each carboxyl or a group of formula II, with the proviso that at least one is the group of formula II; R and R' are each H, methyl or the like; R" is H or methyl; (n) is 2-4]. The precursor is obtained by reacting a tetracarboxylic acid dianhydride (e.g. 4,4- oxydiphthalic acid dianhydride) with a diamine compound (e.g. 4,4'- diaminodiphenyl ether). Preferably, the polyimide precursor is obtained by introducing a side chain to a polyamic acid having 10,000-700,000 weight average molecular weight by using a compound of formula III, [e.g. (N,N- dimethylaminoethoxy)ethyl methacrylate]. |
