本論文研究有機介電材料聚偏氟乙烯-三氟乙烯共聚物[poly(vinylidene fluoride-co-trifluoroethylene)，簡稱P(VDF-TrFE)] 薄膜之介電極化效應，利用外加電場輔助成長具高介電特性之P(VDF-TrFE)薄膜，探討製程環境對P(VDF-TrFE)薄膜結構與特性的影響，並藉由量測金屬-絕緣體-金屬(Metal-Insulator-Metal簡稱MIM)二極體結構之電容，探究P(VDF-TrFE)薄膜結構與介電極化效應之關連性，並進一步研究P(VDF-TrFE)薄膜二極體應用至細菌檢測的可能性。
本論文利用旋轉塗佈搭配外加電場輔助製程，分別於高濕度與低濕度環境下製作多種P(VDF-TrFE)薄膜與對應之MIM二極體，利用阻抗分析儀量測MIM二極體之介電極化效應，並使用差示掃描量熱分析儀、原子力顯微鏡、接觸角量測、X光繞射與拉曼光譜量測，進行P(VDF-TrFE)薄膜結構與表面性質的分析。結果顯示不同濕度條件對製作P(VDF-TrFE)薄膜結構有明顯影響，低濕度環境下，製作之P(VDF-TrFE)為平坦型薄膜；而高濕度環境下，則為孔洞型薄膜。此外，有施予外加電場輔助製程製作之P(VDF-TrFE)試片，相較於未施予外加電場輔助製作之試片，呈現較佳的鐵電極化特性與鐵電相結晶結構，歸因於外加電場可促進P(VDF-TrFE)高分子鏈的電偶極排列方向較均一。最後，將具高電容鐵電特性之低電壓操作的P(VDF-TrFE)二極體元件，應用於細菌感測，當滴上大腸桿菌後，發現具孔洞結構之P(VDF-TrFE)薄膜的元件，其電容特性有顯著變化，證明具特殊結構的高電容鐵電P(VDF-TrFE)薄膜具有應用於感測細菌的潛力。

This study focused on the dielectric polarization effects of organic ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) P(VDF-TrFE) thin film-based metal-insulator-metal (MIM) diodes. Several kinds of the P(VDF-TrFE) thin films were prepared using spin coating technology combined with an external electric field to assist the film formation process, a variety of P(VDF-TrFE) films and corresponding MIM diodes were fabricated under high- and low-humidity environments. Microstructural and electrical polarization properties of the prepared P(VDF-TrFE) thin films were investigated by impedance analysis, differential scanning calorimetry, atomic force microscopy, contact angle meter, x-ray diffraction, and Raman spectroscopy, and the correlation between the electrical and microstructural properties of the deposited films was discussed. The different humidity conditions had a significant impact on the microstructure of the produced P(VDF-TrFE) thin films. In a low humidity environment, the produced film is flat and uniform. In a high humidity environment, it is a porous network film. In addition, the specimens applied with electric field-assisted fabrication of the P(VDF-TrFE) thin films exhibited high capacitance and better ferroelectric polarization characteristics and ferroelectric phase crystal structure than those that were not applied with an auxiliary electric field. The external electric field promoted the alignment of the electric dipole of the P(VDF-TrFE) polymer chain, resulting in better uniformity during the film formation process. The as-prepared porous network P(VDF-TrFE) film-based MIM diodes can be used for bacteria detection. Overall, this study provided useful approaches to develop organic ferroelectric films with high dielectric polarization properties for use in sensing bacteria.

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