苯六甲酸六甲基酯合成交聯型聚亞醯胺研究

Abstract

本研究試驗一個新的密度控制概念，並試圖以此概念設計合適的低介電高分子結構；其利用不同長度之芳香二胺單體及苯六甲酸六甲基酯合成不同的聚亞醯胺交聯系統。以MIM結構量測產物之介電性質，使用TGA量測裂解溫度獲得耐熱性之資料，而FTIR則用以推論內部可能反應及觀察亞醯胺化之行為。同時探討溫度、濃度等反應條件、不同反應物劑量比及加入不同單胺摻雜物對介電性質之影響。實驗結果顯示，當高溫、高濃度、無摻雜物及末端基為酯基之劑量比可得較低之介電係數，介電係數雖有隨單體長度下降之趨勢，然由於亞醯胺化不完全，此系統並不適於低介電材料使用。欲驗證此密度控制理論則需要一更明確定義之多官能基系統。

This work investigated, a density controlling method is order to fabricate the low dielectric constant polyimides (PI). Different cross-linked PI structures were built by aromatic diamines with different length and benzene-hexacarboxylic acid hexamethyl ester. The Al/polyimide/Au/TiW structure on Si wafer was prepared to evaluate its C-V properties. Thermal decomposed temperature was measured by thermal gravimetric analyzer (TGA) to evaluate the thermal stability of those polymer species. Possible reaction mechanisms and the imidization process during thermal curing were studied by Fourier transform infrared spectrophotometer (FTIR). In addition, the relations of reaction conditions and reactant ratios were also discussed. Experimental results indicated that high reacting temperature and concentration of reactants might yield low dielectric constant property. No amine spacer and reactant ratio to obtain ester-ended structure were also beneficial to the reduction of dielectric constant. Nevertheless, the uncompleted thermal imidization process limited the applications of this system to intermetallic dielectrics. A new, well-defined multifunctional scheme was further required to confirm such an unconventional concept evaluated in this work.