以溶液聚合法製備低介電係數聚亞胺薄膜之研究

Abstract

摘 要 本實驗以溶液聚合法（solution polymerization）製備具有低介電常數特性的芳香族聚亞胺。以MIM結構量測聚亞胺之介電常數、崩潰電場和散逸因子，利用TGA量測聚亞胺的熱裂解溫度，並對聚亞胺做黏度和吸濕性測試，量測聚亞胺的固有黏度和吸濕率。黏度量測結果顯示，芳香族聚亞胺的固有黏度範圍是0.45∼0.57 dL/g，在氮氣環境下對聚亞胺所做的熱性質分析結果顯示，聚亞胺5％熱裂解溫度大約486 ~ 498℃，證明聚亞胺具有優良的熱穩定性，實驗結果並顯示聚亞胺具有低介電常數（範圍從2.23∼2.97）、低吸濕性（小於0.6％）和高崩潰電場（範圍從0.86∼3.81 MV/cm）的優點，但散逸因子量測結果顯示，測試頻率超過數個MHz之後，聚亞胺之介電損失特性不盡理想，其有待後續之研究改進。

ABSTRACT Solution polymerization was applied to prepare the low dielectric constant aromatic polyimines and their physical properties were investigated. We evaluated electrical properties of polyimines including dieletric constant, breakdown voltage and dissipation factor. Thermal decomposed temperature of polyimine was measured by thermal gravimetric analyzer (TGA) to evaluate the thermal stability of the polymer specimens. We also measured the inherent viscosity and moisture absorption index of aromatic polyimines. The aromatic polyimines have inherent viscosities of 0.45 ~ 0.57 dL/g. The TGA results showed that the temperatures of 5% weight loss of aromatic polyimines are in the range of 486 ~ 498℃ in nitrogen ambient, indicating that the aromatic polyimines possess excellent thermal stability. Electrical property is measurement indicated that the aromatic polyimines have lower dielectric constant (ranging from 2.23 to 2.97), lower moisture absorption (＜0.6%), and high breakdown voltage (ranging from 0.86 to 3.81 MV/cm). However, dissipation factor measurement revealed that the dielectric loss property of polyimines remains unsatisfactorily when the frequency exceeds several MHz and further study is required.