本研究製作鋅錫氧化物（Zinc Tin Oxide, ZTO）單層與ZTO / (N,N’-Ditridecylperylene-3,4,9,10-tetra-carboxylic diimide, PTCDI-C13)雙層為主動層之光偵測器，探討其在不同環境溫度(25-150 °C)下，對綠光和紫外光的感測和仿突觸學習行為，並使用手寫辨識平台進行圖形辨識驗證仿神經形態的計算潛力。
採用溶液製程製作ZTO氧化物底層，利用物理氣相沉積PTCDI-C13上層，製作ZTO / PTCDI-C13雙層堆疊主動層，利用紫外-可見光光譜、光激發螢光光譜、X光繞射儀(簡稱XRD)、和X光光電子能譜(簡稱XPS)進行薄膜特性分析，並探討溫度對元件的光電特性的影響。在實驗的溫度範圍下， ZTO 吸收波段未有明顯變化，而PTCDI-C13薄膜的0-0 電子躍遷則隨溫度上昇出現部份不可逆藍移現象，可歸因於加熱對其薄膜微結構的改變， XRD量測也證實變溫對PTCDI-C13的結晶繞射峰產生不可逆變化。ZTO單層與ZTO / PTCDI-C13雙層均觀察到熱擾動致光激發螢光淬滅效應。XPS分析指出ZTO單層在變溫下，會發生脫附與吸附氧缺陷的可逆反應，而ZTO / PTCDI-C13雙層的氧鍵結未觀察到明顯變化。單層與雙層元件在未照光與照光下，均發現元件的電流隨溫度上昇而增加，當照射紫光時，可明顯增益高溫下的電流輸出，並提昇電流的記憶持久力，相較之下，照射綠光時，元件的電流輸出僅有小幅增加，且呈現無記憶特性的數位式反應。
將元件的紫外光感知特性應用於模擬神經突觸行為。在單脈衝光刺激下，單層與雙層元件皆可模擬興奮型突觸後電流(簡稱EPSC)，且在不同溫度下表現出不同的EPSC與光脈衝寬度的相依性。當使用雙脈衝光刺激時，元件則表現出成對脈衝促進(簡稱PPF)，當達100 °C 時有最穩定的PPF 比值。進行多脈衝光刺激時，元件在不同溫度下表現出迥異的長期增益 / 長期抑制行為(簡稱LTP / LTD)，在100 °C 時LTP / LTD 行為表現出最佳的線性度與動態範圍。最後，將元件的光感知特性應用至手寫辨識平台進行圖形辨識模擬，發現隨環境溫度改變，元件也表現出不同的辨識能力，將有機會應用在需要感知溫度的仿神經形態的計算。

We fabricated zinc tin oxide (ZTO) single-layer and ZTO/N,N′-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI) bilayer photodetectors to study temperature-dependent (25 ~ 150 °C) photoresponse and synaptic behaviors under UV light and green light illumination. The characteristics of the ZTO and ZTO/PTCDI films were analyzed using UV–visible spectroscopy, photoluminescence (PL) spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), while the influence of temperature on the devices’ optoelectronic properties was also investigated. The results indicate that the ZTO/PTCDI bilayer films exhibit partially irreversible microstructural changes. XPS revealed reversible oxygen desorption and vacancy interconversion in the ZTO film. Both devices showed increasing dark and photocurrents with rising temperature. Under UV illumination, the devices exhibited greatly enhanced current and retention characteristics at elevated temperatures, whereas green light induced a much smaller current enhancement without noticeable memory behavior. Upon UV light pulse stimulation, the devices emulated excitatory postsynaptic currents and demonstrated temperature-dependent long-term potentiation/depression behavior. Finally, handwriting recognition simulations confirmed temperature-dependent recognition accuracy, highlighting the potential of ZTO-based devices for temperature-adaptive in-sensor neuromorphic computing.

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