以濺鍍時環境氣體條件改變氧化鋅(ZnO)薄膜的缺陷含量，製備以n-ZnO/p-Si為基礎的兩端點元件(two-terminal devices)，探討製備條件對電鑄(electroforming)與電阻態轉換(resistance switching)特性的影響。拉曼散射中因電子-聲子交互作用增強的LO聲子振模，以及光致螢光中激子放射(excitonic emission)特徵確認薄膜中的纖鋅礦氧化鋅(wurtzite ZnO)結構。穿透光譜中顯著的Urbach tails反映源於低氧供應濺鍍所致氧空缺與間隙鋅之高密度能隙邊緣電子態，可解釋元件表現的較低電阻轉換比。本研究追蹤電鑄與雙極、單極電阻態轉換過程中的電流、電壓關係以及讀取電阻演化，討論傳導氧化物膜層中傳導機制，並分析電阻轉換臨界條件的普適尺度行為(universal scaling behaviors)。

Defect content was varied by tuning the ambient gas conditions during sputtering zinc oxide (ZnO) for fabricating two-terminal devices based on n-ZnO/p-Si. Effects of preparation conditions on electroforming and resistance switching processes have been investigated. Electron-phonon coupling-enhanced LO Raman modes and excitonic photoluminescence evidenced the films’ wurtzite ZnO structure. Prominent Urbach tails observed in transmission spectra reflected high density of near-band-edge states of oxygen vacancies and zinc interstitials due to low oxygen supply during deposition. This may account for the reduced resistance switching ratios. Current-voltage relations and read resistance were followed to reveal the mechanisms dominating the carrier conduction in oxide films. Universal scaling behaviors of the critical conditions resulting in resistance switching will be discussed. 

第１章 文獻回顧與研究問題 1
第２章 實驗方法 7
2.1 樣品制備 7
2.2 分析方法 8
2.2.1電性量測 10
第３章 實驗結果 13
3.1 薄膜光學性質 13
3.1.1穿透光譜 13
3.1.2拉曼散射(325&532nm) 15
3.1.3光致螢光 16
3.2 電性量測 18
3.2.1電鑄過程 18
3.2.2雙極轉換(bipolar switching) 24
3.2.3 單極轉換(unipolar switching) 31
第４章 討論與結論 35
實驗結果總結 35
臨界條件普適尺度行為(universal scaling) 38
參考文獻 41

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