MoTe2因其1T'/2H相變特性與優異的電學性質，在次世代非揮發性記憶體與神經形態運算元件中展現高度潛力。然而，目前多數相變控制技術存在不可控的混相生成與繁瑣的多段半導體製程流程，限制其實際應用與整合性。本研究提出一種新穎、簡單且具高度可控制性的1T'/2H相控制方法，透過對Mo薄膜施加機械刮痕引入局部應力場，成功實現2H相之選擇性控制，並進一步製作1T'/2H/1T' 結構之無金屬電極憶阻器元件。相較傳統依賴退火或外加電場的方式，本技術能有效控制異質相界面的位置與尺寸。結合DFT模擬，探討−6%至+9%應變與Mo原子密度下兩相的自由能變化，結果顯示受壓應變之1T'相具有較高的自由能，進而有利於2H相轉換，驗證應力誘導相變的可行性。元件測試顯示，該憶阻器元件具穩定的雙極性切換行為、超過120次的耐久性與10000秒以上的資料保持能力。此外，透過脈衝刺激觀察到突觸短期加強與衰退現象，顯示其具備突觸可塑性。整體而言，本研究提供一種高效可控之相變工程策略，並展現MoTe2於非揮發記憶體與神經形態元件中的潛力與應用價值。

MoTe2 with its inherent 1T'/2H phase transition capability and outstanding electrical properties, has emerged as a promising candidate for next-generation non-volatile memory and neuromorphic computing devices. However, current phase engineering strategies are often hindered by uncontrollable mixed-phase formation and complex multi-step semiconductor processing, which limit their practical applicability and scalability. In this study, we propose a novel, facile, and controllable method for phase control by introducing localized strain fields via mechanical scratching on Mo films, enabling selective stabilization of the 2H phase. A 1T'/2H/1T' heterostructure memristor was subsequently fabricated without the need for metal electrodes. Compared to conventional phase-control approaches based on thermal annealing or electric-field-driven transformation, this technique provides precise control over the location and size of phase boundaries. Density functional theory (DFT) calculations further support the experimental observations, revealing that under compressive strain (−6% to +9%) and varying Mo atomic densities, the 1T' phase exhibits higher free energy than the 2H phase, thus favoring a strain-induced 2H transformation pathway. Electrical measurements confirm the memristor exhibits robust bipolar switching behavior, endurance over 120 cycles, and data retention exceeding 10000 seconds. In addition, short-term potentiation and depression were demonstrated under pulsed stimuli, indicating synaptic plasticity. Overall, this work presents an efficient and scalable phase engineering strategy and highlights the potential of MoTe2-based heterostructures in future non-volatile memory and neuromorphic sytems.

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