Abstract
A novel photosensitive polymer with main chain polyhedral origomeric silsesquioxane (POSS) was synthesized using hydrosilylation polymerization of dihydrosilane POSS and tetrahydropyranyl (THP) group containing di-yne derivatives and subsequent deprotection reaction without no side reactions. The obtained polymer was applied as a negative-working photoresist system with 4,4'-methylenebis[2,6-bis(hydroxymethyl)] phenol as the acid crosslinker and (5-propylsulfonyloxyimino-5H-thiophene-2-ylidene)- (2-methylphenyl)acetonitrile as the photoacid generator under 436 nm light and 2.38 wt% tetramethylammonium hydroxide aqueous solution/2-propanol (50:50, v/v). Under optimized condition, the three component resist system was able to generate sharp, 4 μm line patterns and the sensitivity characteristic curve indicate its sensitivity (D0.5) and contrast (γ0.5) are 31 mJ/cm2 and 3.1, respectively. Patterned film was crosslinked by thermal treatment at 300 °C and cured film shows enhancement of thermal stability such as 410 °C of thermal decomposition temperature (Td5) and above 300 °C of grass transition temperature (Tg). Furthermore, cured film indicates 2.77 of dielectric constant fairly same as matrix polymer of 2.78.
