有機半導體高分子材料構成之軟性電子元件性能，主要取決於高分子於微觀結構上有序排列。由於半導體高分子之導電性來自於主鏈內共軛鍵結讓載子傳遞，主鏈的分子構型、堆疊等微觀結構差異都會影響鏈上電子結構，混亂堆疊、扭曲型態會產生形貌與電子結構缺陷，將大幅增加載子散射影響，導致載子無法於水平方向有效傳輸，造成巨觀水平傳導效能低落，因此高分子微觀結構與載子傳導效能密切相關。本研究旨在藉由原子力顯微鏡（AFM）奈米級探針技術與變頻率之電化學阻抗頻譜（EIS）結合，以AFM導電探針作為微型電極，將量測範圍聚焦於奈米尺度之半導體高分子膜，觀測載子微觀動力學與介面行為，建立半導體高分子微觀結構與電學性能間聯繫的分析方法學。
本研究選用聚(3-己烷塞吩)（Poly(3-hexylthiophene-2,5-diyl)，P3HT）半導體高分子材料，首先以旋轉塗佈法（spin coating）、於矽基板及二氧化矽基板兩種基板上，製備無序均質P3HT半導體高分子薄膜，並分別建立垂直與水平測試架構、量測阻抗頻譜，隨後擬合各量測系統對應之等效電路模型。由於探針於所有量測中皆為垂直接觸高分子膜表面，故先透過垂直架構分析不同基板、不同膜厚之薄膜載子電學行為，結果顯示其符合半導體介於導體與絕緣體間、可呈現載子傳導與介電累積行為之電學特性。在此基礎上，通過水平架構比對等效垂直模型之差異，發現電力線走向確實可在薄膜中即轉向水平、使載子於水平方向上傳輸，驗證了水平架構的可行性，為後續量測本實驗室開發之三明治製程（sandwich process）形成之有序P3HT薄膜建立基礎。

The conductivity of semiconducting polymers is influenced by charge transport through the π-conjugated backbone. Microstructure variations like disordered stacking or twisted formations can create defects that result in carrier scattering and poor lateral conductivity. Therefore, the electrical performance of flexible organic polymeric devices depends on molecular ordering of the microstructure.
In this study, we utilized AFM-based nanoscale impedance spectroscopy to analyze variable-frequency AC signal responses of semiconducting polymers. By using AFM probes as microelectrodes, we focused on nanoscale semiconducting polymer films to investigate carrier dynamics or accumulation behaviors, aiming to link the microstructure with electrical performance.
For simplicity, macroscopic homogeneous spin-coated poly(3-hexylthiophene-2,5-diyl) (P3HT) films were prepared. The measurement was divided into vertical and horizontal parts, with equivalent circuit models fitted to the impedance spectroscopy data for each. As the AFM probe contacts the films vertically in all systems, we first measured vertical part, revealing that P3HT films indeed demonstrate behaviors between conductors and insulators, including conduction and dielectric accumulation. Additionally, comparing the horizontal and vertical fittings revealed that the electric field lines can reorient horizontally within the film, enabling lateral carrier transport. This confirms the feasibility of the system and establishes a further measurement foundation for ordered sandwich-processed P3HT films.

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