有機電子學可透過溶液製程大面積製作電子元件，相較於傳統半導體製程不需使用高真空、高溫等高碳排技術，十分符合追求環境與能源永續的未來科技。但現行液相製程缺少能在分子層級有效控制溶質溶解、析出、成核、沉積等跨相動力學的架構，混亂的分子間作用力降低製程精度、形貌也缺少可重複性，使得電子元件效能低下而為人詬病。若要以高精度與可靠度液相製作高效電子元件，必須要建立能可靠分析薄膜形貌相依電子結構的實驗方法，才能連結分子尺度的固－液相轉變產生的形貌變異，有效回饋修正分子級製程參數。這需以非破壞性、原位（in situ）整合多種頻譜學手段同時分析分子排列與電子結構，無法如現行實驗般多機台分別量測不同光電與排列特性。
本研究團隊為補足現行方法學的缺憾，建立一套共軛顯微鏡架構之多工頻譜儀，同時整合反射式可見光吸收、螢光（photoluminescence, PL）與拉曼散射（Raman scattering）頻譜系統，於焦點原位量測分子排列與電子結構訊息。更以實測數據辯證，建立專屬此系統的薄膜光學模型，分析形貌－激子耦合、形貌－應力等基本作用力，以比較不同製程條件產生的導電高分子有序性差異，整合並強化製程－電子結構的連結，以最佳化分子級製程參數窗口。
材料使用聚(3-己基噻吩)（poly(3-hexylthiophene, P3HT），其薄膜之光電性質可敏感響應分子鏈段構形、排列、聚集態（aggregate）激子交互作用。十分適合以頻譜學手段分析上述分子級電子結構。在反射光譜量測方面，本研究利用高角度掠射減低矽基板吸收，增加界面反射次數，拉長光線往返通過P3HT薄膜的路徑長度，成功提高薄膜光學響應的敏感度。考量反射光譜同時受到薄膜折射率、消光係數、膜厚、基板性質及多重反射等因素影響，本研究進一步建立以光學常數 (n) 與 (k) 為基礎之模型，並結合轉移矩陣法（transfer matrix method, TMM）檢驗量測光譜的物理合理性與薄膜吸收特徵。
在完成光學模型驗證後，本研究結合吸收與螢光光譜，利用弗倫克爾–霍爾斯坦模型（Frenkel–Holstein model）與 Spano 聚集態模型（Spano aggregate model），分析 P3HT 分子鏈內與鏈間交互作用，並比較不同薄膜有序性的有效激子耦合強度，以及H 型與 J 型特性隨薄膜有序性變化而消長，強化分子級有序性與電子結構的連結，以分析溶液製程固－液轉換時的分子應力變化。為提高實驗與模型比較的一致性，模擬光譜與實驗數據採用相同之光譜處理與特徵擷取方式，並透過加入額外干擾的模型測試，評估分析結果之穩定性與可信範圍。最後，本研究比較不同單分子嫁接密度對P3HT分子排列、鏈段構形、聚集能態與激子交互作用的影響。實驗結果說明可透過調控單分子密度改變分子鏈段構形與聚集能態，進一步影響 P3HT 薄膜中的激子耦合與光學性質。
本研究建立一套由整合共軛反射式吸收、螢光、拉曼散射頻譜學系統，量測並辯證薄膜形貌－光電特性的完整流程。透過多工頻譜學手段先確認物理合理性，再進一步探討其微觀分子結構與激子響應的關聯，降低量測中的基板效應，並提供可靠度高、可重現性的P3HT薄膜形貌－電子結構特性的多工頻譜方法學。

Solution-processed organic electronics enable large-area, low-carbon fabrication, well suited for energy sustainability though remain limited by the lack of in-situ techniques capable of simultaneously probing and intercorrelating molecular order/disorder and electronic structures to enable feedback control process parameters. Lack of control over molecular packing results in poor film reproducibility and degrades device performance. In this work, we integrate polarized reflective absorption, photoluminescence (PL), and Raman scattering to construct a confocal-microscope-based multi-modal spectroscopic platform that can characterize molecular orientation-and rigidity-dependent electronic structures at a single focal point.
A theoretical framework combined with the transfer matrix method (TMM), Frenkel–Holstein and Spano HJ aggregate models was established to validate the physical consistency of the spectral analysis. Poly(3-hexylthiophene) (P3HT) on self-assembled monolayers with a series of densities was employed as the model materials. Grazing-incidence reflective absorption spectroscopy was adopted to suppress substrate interference and enhance detection sensitivity. Intrachain and interchain excitonic interactions were analyzed to correlate molecular ordering and rigidity with electronic structures. The influence of grafting density on chain conformations, aggregation, and excitonic coupling was further investigated. The results demonstrate that grafting density effectively modulates aggregation behavior and optical properties, accompanied by systematic changes in H-like and J-like excitonic characteristics.
This work establishes a confocal multi-modal spectroscopy platform integrating polarized reflective absorption, PL, and Raman scattering to provide a reliable methodology of characterizing morphology-dependent electronic structures while minimizing substrate effects. The proposed approach offers a promising tool for investigating solution-processed organic electronic materials.

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