本論文藉由層層改善rr-P3HT有機薄膜電晶體的參數，藉以得到最佳化之rr-P3HT薄膜電晶體，進而研究其相關機制與應用。此研究成果分為兩個部分:
第一部分:選擇有機半導體rr-P3HT之溶劑與調變修飾層PMMA的分子量及濃度並且改善rr-P3HT成膜的後處理方式，因此，得到高效率、高穩定之rr-P3HT薄膜電晶體，此電晶體的電流開關比可達105、次臨界擺幅約1 V/dec、載子遷移率約為3×10-2 cm2/Vs。使用電容分析此元件之物理特性，發現rr-P3HT與修飾層PMMA之介面能造成極化效應(dipole effect)，使得此元件之電流能夠在長時間操作下穩定且難以衰減。
第二部分:探討最佳化rr-P3HT薄膜電晶體的表面形貌，利用簡易的後處理變溫方式得到不同的形貌，並挑出兩種變化進行後續的應用實驗:氣體感應器、記憶體元件測試。由於後處理的不同，兩種元件之rr-P3HT薄膜經由原子力顯微鏡觀察出其表面形貌擁有不同大小、深度及密度的微米孔洞。此結構經由二維拉曼光譜分析以得到初步的分子排列組合之依據，後續經由氣體感應器與記憶體元件測試應用，可更進一步的探討孔洞能扮演的角色與它們真正的物理機制。

Organic thin film transistors processed on silicon dioxide (SiO2) substrates generally possess unstable electrical characteristics. This study attempted to achieve high performance and stability for regioregular poly(3-hexylthiophene) (rr-P3HT) thin film transistors (TFTs). The electrical performance of the rr-P3HT-based TFTs was significantly improved by optimizing the fabrication process of the rr-P3HT active layer and the poly(methyl methacrylate) (PMMA) gate dielectric buffer layer. The on/off ratio reached 105, the subthreshold swing was as low as ~1 V/dec, and the hole mobility was 3 × 10−2 cm2/Vs. Capacitance analysis revealed the significant dipole effects of the interface between the rr-P3HT and the PMMA. This result provides a reasonable explanation for the improved operational stability of the rr-P3HT-based TFTs.

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