本論文研究以P型苯並二噻吩和苯並二噻吩二酮交替共聚衍生物 (簡稱PBDB-T)、N型二酮吡咯並吡咯和雙氰基噻吩乙烯交替共聚衍生物 (簡稱2DPP-2CNTVT) 與氧化鋅錫 (Zinc Tin Oxide, ZTO) 作為主動層之薄膜電晶體與兩端元件，透過多種材料的堆疊與混參，製作出能夠進行多波段廣域光感測的元件，並應用在仿生突觸行為與神經網絡的計算。本研究主要可分為四個部分，首先分析不同材料架構之薄膜的內部結構與光學特性；接著探討在不同波段光照下兩端薄膜元件的電特性與突觸特性；再進一步討論在不同波段光照下三端薄膜電晶體的電特性與突觸特性；最後一部分則進行元件的仿生突觸行為應用在神經網絡的計算分析。
第一部分探討在玻璃基板與ZTO薄膜上堆疊PBDB-T單層、2DPP-2CNTVT單層與PBDB-T/2DPP-2CNTVT雙層的微結構與光學特性的差異。發現在玻璃基板上PBDB-T/2DPP-2CNTVT雙層薄膜具有良好的表面平整性，而在ZTO薄膜上的雙層薄膜則呈現島狀結構。吸收光譜證實ZTO/PBDB-T/2DPP-2CNTVT 多層薄膜實現了多波段廣域 (200 - 1000 nm) 的吸收。拉曼光譜指出2DPP-2CNTVT在雙層薄膜中具有比在單層薄膜中更延伸的共軛平面結構。光激發光譜量測指出PBDB-T與2DPP-2CNTVT的界面間會有電荷轉移效應。
第二部分的結果顯示，在兩端操作下，主動層為單層PBDB-T的元件表現出具有記憶性的類比式反應，照光後所產生的電荷並不會馬上流失；而單層2DPP-2CNTVT的元件則表現出不具有記憶性的數位式反應，照光後所產生的電荷會馬上流失；PBDB-T/2DPP-2CNTVT的雙層堆疊與混參元件皆會得到不具有記憶性的數位式反應，但在ZTO薄膜上的雙層薄膜並照射紫外光，可以重新得到具有記憶性的類比式結果，顯示出該元件具有不同波段的光辨識、光感測與儲存電荷的能力。
第三部分的結果顯示，在三端操作下，在單層PBDB-T中混參2DPP-2CNTVT之後，會產生PN接面阻礙通道內部載子的傳輸，讓電流水平下降。將元件置於在照光環境下，皆會由於光生載子的產生而讓電流水平提升。在突觸行為的部份，元件皆有成功模擬出興奮性突觸後電流 (EPSC)、成對脈衝促進 (PPF) 與長期增強作用 (LTP) /長期抑制作用 (LTD) 行為，且在照光的環境下各項突觸權重指標皆有優化。
最後一部分則是將多突觸刺激的量測結果所得出的突觸權重參數應用在神經網絡的辨識率計算之中，皆可以得到接近理想值的辨識率，也與突觸權重參數的結果相互呼應，表示突觸權重與正確率是會相互影響的。

This dissertation investigates electrical characterization of thin-film transistors and two-terminal optoelectronic devices that employ, as active layers, a p-type alternating copolymer derivative of benzodithiophene and benzodithiophene-dione (PBDB-T), an n-type alternating copolymer derivative of diketopyrrolopyrrole and dicyanovinyl-thiophene-vinylene (2DPP-2CNTVT), and zinc–tin oxide (ZTO). By engineering multilayer stacks and mixed-blend formulations among these semiconductors, we realize devices that exhibit broadband, multiband photodetection spanning the ultraviolet–visible–infrared windows. The material platform further enables optoelectronic synaptic functions, including memory characteristics and paired-pulse behaviors, thereby supporting biomimetic synapse emulation. Leveraging these characteristics, we demonstrate neuromorphic computation in which optical inputs are sensed, weighted, and processed within the device structure, illustrating an in-sensor computing pathway. The results establish PBDB-T/2DPP-2CNTVT/ZTO heterostructures as a promising route to low-power, multifunctional hardware that unifies multiband sensing with synaptic plasticity, and they provide a material–device framework for future flexible systems integrating sensing, memory, and computation on a single platform.

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