New fluorinated polyimides for advanced microelectronic applications

A series of fluorinated polyimide films have been prepared by casting the poly (amic acid) solution, which were synthesized by polycondensation of 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) with various fluorinated aromatic diamines, including 1,4-bis (4-amino-2-trifluoromethylphenoxy) benzene (p6FPB), 4-[3', 5'-bis-(trifluoromethyl) phenyl]-2,6-bis (4"-amino-phenyl) pyridine (pTFPP) and 4-[3',5'-bis-(trifluoromethyl phenyl)-2,6-bis (3"-aminophenyl) pyridine] (mTFPP), followed by thermal imidization at elevated temperatures. The strong and flexible polyimide films, PI-1 (6FDA-p6FPB), PI-2 (6FDA-pTFPP) and PI-3 (6FDA-mTFPP) exhibited good thermal stability and high mechanical properties. The films also showed high surface and volume resistances and low dielectric constant. The excellent combined properties of the materials make them great candidates for microelectronic packaging.