本研究設計並製作一種電晶體結構有機壓力突觸感測器，其中主動層為聚三己基噻吩(poly(3-hexylthiophene), P3HT)，介電層為由聚偏二氟乙烯（polyvinylidene difluoride, PVDF）與離子液體1-乙基-3-甲基咪唑鎓/雙(三氟甲基磺酰)(1-Ethyl-3-methylimidazolium/bis(trifluoromethyls-ulfonyl)imide,[EMIM][TFSI])混摻形成的高電容離子凝膠。離子凝膠兼具高離子導電性與可極化性，在外加壓力下能形成穩定的電雙層(Electric Double Layer, EDL)，產生等效閘極電壓以驅動通道導通。P3HT負責載子傳輸並模擬突觸後電流(Post-synaptic Current, PSC)，實現具仿生突觸的壓力感測行為。
實驗結果顯示，感測器在12.9~319.3 kPa的壓力範圍內皆能產生明顯的電流響應，靈敏度隨壓力增強而上升，最高可達約150 A/kPa，反應時間小於0.5 秒。元件可辨識不同頻率的機械刺激(0.25~10 Hz)，並在單脈衝與雙脈衝刺激下展現興奮性突觸後電流與成對脈衝促進等仿生突觸行為，衰退時間約為65 ms，與生物皮膚中帕西尼氏體的快速適應性相當。穩定性測試顯示，經多次循環後元件輸出依然穩定，證明其具備良好的可重現性與結構耐受性。進一步藉由光譜分析揭示其壓力響應機制：拉曼與光致發光光譜顯示壓力使P3HT的C=C振動峰產生藍移與半高寬增加，表示分子共軛鏈被扭曲、電子耦合減弱。XPS深度分析則證實離子在壓力下重新分佈，負離子(TFSI⁻)主要停留於介面形成電荷補償，而正離子(EMIM⁺)可滲入P3HT主鏈造成暫態摻雜。PVDF的β相結構促進離子排列，進一步增強離子凝膠的極化能力並穩定EDL形成，使壓力與離子摻雜共同改變電晶體的電特性與通道導電性。
本研究證明離子凝膠介電層與有機半導體的耦合可有效將機械刺激轉換為可控的電訊號，並展現仿生突觸特性。此電晶體式有機壓力突觸感測器具備低操作電壓、高靈敏度與穩定重現性，展現出應用於電子皮膚、智慧醫療與神經感測系統的潛力。

We developed organic transistor based pressure sensors using P3HT as the active layer and a PVDF/[EMIM][TFSI] high capacitance Ion gel as the dielectric. Under applied pressure, a stable electric double layer (EDL) forms at the P3HT/Ion gel interface, modulating the channel current to mimic postsynaptic current (PSC). The devices respond to pressures of 12.9~319.3 kPa with high sensitivity (~150 μA/kPa), can detect 0.25~10 Hz stimuli, and exhibit EPSC and PPF behaviors with fast decay (~65 ms) and stable longterm performance. Spectroscopic analyses show pressure induced P3HT chain torsion and spectral blue shift, while XPS confirms interfacial charge compensation by TFSI⁻ and channel doping by EMIM⁺. The β phase of PVDF further enhances ionic polarization and EDL formation, improving channel conductance and synaptic output. These results demonstrate effective mechano electrical transduction with synaptic plasticity, low operating voltage, high sensitivity, and good reproducibility, offering potential for electronic skin, smart healthcare, and neuromorphic sensing applications.

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