臺灣博碩士論文加值系統

電阻記憶體因具備增益抑制、長短期可塑性、長短期記憶效應及
時序相關可塑性等特性，是目前作為電子突觸元件來模擬人工突觸最
具潛力元件，故本論文利用氧化鈦及氧化矽為切換層製作
Ni/TiOx/TiOy/TiN 及 Ni/TiOy/SiO2/TiN 元件並探討其電子突觸特性。
第一部 及第二部份為 分 別 量 測 Ni/TiOx/TiOy/TiN 及
Ni/TiOy/SiO2/TiN 結構元件之電子突觸特性，透過連續電壓掃描確認
元件具備增益與抑制特性，並探討連續掃描對於元件能障變化，後續
利用不同脈衝波形量測元件突觸增益與抑制、長短期記憶特性及成對
脈衝促進，並計算其非線性度、記憶時間及成對脈衝促進。
Ni/TiOx/TiOy/TiN 元件相較於 Ni/TiOy/SiO2/TiN 在增益部分能障
變化由 0.58 ~ 0.554 eV 提升至 0.698 ~ 0.628 eV，抑制部分能障由 0.498
~ 0.538 eV 提升至 0.594 ~ 0.702 eV；增益與抑制部分以脈衝寬度 250
µs 及脈衝電壓-1 V/1 V 作探討，非線性度由 3.01 %與 5.98 %降至 1.6
%與 2.27 %，電導變化由 19 %降至 8.05 %，Ni/TiOx/TiOy/TiN 元件線
性度較差但電導變化比較大；由鬆弛時間可以看出 Ni/TiOy/SiO2/TiN
元件具有較好的長短期記憶特性；成對脈衝促進時間由 0.2 s 提升至
3 s，可以看出 Ni/TiOx/TiOy/TiN 元件在維持電導狀態較佳。

RRAM devices posses characteristics such as potentiation and
depression, short- and long-term plasticity, short- and long-term memory,
and spike-time-dependent plasticity. It is currently the most promising
electronic synaptic element for simulating artificial synapses. Therefore,
this thesis used titanium oxide and silicon dioxide as the switching layers
to fabricate Ni/TiOy/TiOx/TiN and Ni/TiOy/SiO2/TiN devices and
investigate their electronic synaptic characteristics.
The first and second parts measured electron synaptic characteristics
of Ni/TiOy/TiOx/TiN and Ni/TiOy/SiO2/TiN structural devices,
respectively. Through cyclic scanning, the devices were confirmed to
possess potentiation and depression properties. Then, different pulse
waveforms were used to demonstrate synaptic potentiation and depression,
short and long-term memory characteristics, and paired-pulse facilitation
of the devices. Nonlinearity, memory time, and paired-pulse facilitation
were then calculated.
Compared with the Ni/TiOy/SiO2/TiN device, the Ni/TiOy/TiOx/TiN
device had larger change in barrier for potentiation (0.698~0.628 eV) and
depression (0.594 eV~0.702 eV). The Ni/TiOy/SiO2/TiN device had
nonlinearities of 1.6 % (potentiation) and 2.27 % (depression), but
Ni/TiOy/TiOx/TiN device had larger change in conductance ratio (19 %), PPF index of 3 s, and Ni/TiOy/SiO2/TiN had long relaxation time at longterm and short-term memory characteristic

中文摘要 I
ABSTRACT II
致謝 IV
目錄 V
圖目錄 VII
表目錄 X
第一章 緒論 1
1-1 前言 1
1-2 研究動機與目的 1
1-3 論文架構 1
第二章 文獻回顧與基礎理論 3
2-1 電阻式記憶體簡介 3
2-1-1 切換特性 3
2-1-2 轉態機制 5
2-2 電阻式記憶體的發展 5
2-3 電流傳導機制 6
2-4 電子突觸特性介紹 8
2-4-1電阻式記憶體應用於電子突觸元件 10
2-4-2電阻式記憶體與電子突觸元件差異 13
2-5 電子突觸記憶特性介紹 14
2-5-1 增益與抑制 14
2-5-2 長短期記憶 15
2-5-3 成對脈衝促進 16
2-5-4 脈衝時序依賴可塑性(STDP) 16
2-6 電阻式記憶體類比改善 17
2-6-1製程改善 17
2-6-2電壓調變 19
第三章 實驗步驟 21
3-1 實驗流程說明 21
3-2 實驗設備 22
3-3元件製備流程 25
3-4 電性分析 27
3-5材料分析 30
第四章 結果與討論 32
4-1 Ni/TiOx/TiOy/TiN元件類比特性與機制探討 32
4-1-1 元件製備流程與材料化學鍵結分析 32
4-1-2 元件電阻及電導切換機制 34
4-1-3 增益與抑制分析 39
4-1-4 長短期記憶分析 43
4-1-5成對脈衝促進分析 43
4-2 Ni/TiOy/SiO2/TiN元件類比特性與機制探討 45
4-2-1元件製備流程 45
4-2-2元件電阻切換機制 45
4-2-3 增益與抑制分析 50
4-2-4 長短期記憶分析 54
4-2-5成對脈衝促進分析 55
第五章 結果與未來展望 57
5-1結論 57
5-2未來展望 59
參考文獻 60

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