為了釐清元件發生Reset過程的機制，利用Ti/HfO2/TiN簡單結構的電阻式記憶體（RRAM），以Constant Voltage Sampling變溫量測，其過程符合電化學一級反應，經由公式計算後萃取其活化能Ea，得到三種不同的活化能，提出Reset過程中的物理機制模型。
將銦錫氧化物（ITO）之透明導電膜取代金屬電極有更多的好處，可使RRAM操作電流下降、Set電壓小，以及自限流之特性等優點。因此設計與製作ITO作為上電極的電阻式記憶體，藉由電流機制傳導擬合，提出氧離子能驅趕進入ITO電極，且金屬阻絲能夠鑽入電極中，在金屬阻絲附近形成半球形似半導體區域之模型。ITO/SiO2:ITO/TiN之元件，可同時擁有介面型電阻切換與阻絲型電阻切換，在介面型操作下，當截止電壓增加時，造成低電阻態的電阻值明顯下降，對此現象進一步探討，並驗證了ITO材料可作為氧離子儲存槽。阻絲型操作下有良好的可靠度，且耐受度可達10^8次以上之優異表現。
最後希望能將研究推廣至未來電子產品的應用，製作互補式電阻切換之結構克服RRAM在陣列上所造成的潛行電流問題。本實驗利用銦錫氧化物電極的Set與Reset電壓不對稱之特性，使其讀取區間大於金屬電極，可降低誤判的機率。除了以電極模板設計，亦製作由兩顆RRAM反向串接之結構，於DC sweep cycle可達1000次以上穩定操作。

In order to clarify the mechanism of reset process in Ti/HfO2/TiN resistive random access memory (RRAM) devices, constant voltage sampling measurements are carried out at different temperatures. The reset process is dominated by electrochemical first order reaction. Three different values of activation energy are extracted in the reset process, and the corresponding dominant models are proposed in this thesis.
Transparent conductive film of indium tin oxide (ITO) possesses plenty of benefits over metal electrode, including lower operating current, low set voltage, and self-limiting current characteristic. Therefore, ITO is designed and fabricated as the top electrode, and oxygen ions are verified to be driven into the ITO electrode by current fitting. Moreover, experimental results demonstrate that ITO/SiO2:ITO/TiN devices can exhibit either interface type or filament type resistive switching depending whether forming process is performed. As operating voltage increases, the resistance of the low resistance state decreases, verifying that ITO can be regarded as an oxygen ion reservoir. Besides, the fabricated sample reveals good retention behavior and endurance up to 10^8 times.
In order to make the RRAM devices practical in the future electronic products, complementary resistive switching structure is proposed and fabricated to eliminate the sneak path current in RRAM crossbar array. In this study, due to the property of asymmetric set and reset voltages of ITO electrode, ITO is utilized to realize a larger reading window and minimize the misidentification when compared to that with metal electrodes. Besides electrode pattern designing, the structure of two bipolar RRAM elements antiserially into one complementary resistive switching memory is also fabricated, and can exhibit stable DC sweep cycles up to 1000 times.

摘要 ii
Abstract iii
誌謝 v
目錄 vi
圖目錄 ix
表目錄 xiii
第一章 序論 1
1-1 前言 1
1-2 研究目的與動機 2
第二章 文獻回顧 3
2-1 記憶體簡介 3
2-1-1自旋力矩轉移-磁阻式隨機存取記憶體（STT-MRAM） 3
2-1-2相變化隨機存取記憶體（PCRAM） 4
2-1-3電阻式隨機存取記憶體（RRAM） 5
2-2 傳導路徑之電阻切換機制 5
2-2-1 介面型電阻切換機制 6
2-2-2 阻絲型電阻切換機制 6
2-3 絕緣層之載子傳導機制 6
2-3-1 歐姆傳導（Ohmic conduction） 7
2-3-2 蕭特基發射（Schottky emission） 7
2-3-3 普爾-法蘭克發射（Poole-Frenkel emission） 8
2-3-4 跳躍傳導（Hopping conduction） 8
第三章 定電壓下電阻式記憶體Reset過程之機制研究 12
3-1 實驗動機 12
3-2 氧化鉿薄膜電阻式記憶體元件 12
3-3 化學反應級數測量 12
3-4 化學反應活化能 萃取 14
3-5 實驗結果機制探討 15
3-6 模型 15
第四章 鉿摻雜於二氧化矽薄膜電阻式記憶體 25
4-1 實驗動機 25
4-2 ITO/Hf:SiO2/TiN元件製備 25
4-3 Hf:SiO2薄膜材料分析 26
4-3-1 Hf:SiO2之FTIR分析 26
4-3-2 Hf:SiO2之XPS分析 26
4-4 Hf:SiO2 RRAM元件基本特性 26
4-5 Hf:SiO2 RRAM元件電流傳導機制擬合 27
4-6 Hf:SiO2 RRAM元件電流傳導機制模型 27
第五章 二氧化矽摻雜於銦錫氧化物薄膜電阻式記憶體 36
5-1實驗動機 36
5-2 ITO/ SiO2:ITO/TiN元件製備 36
5-3 SiO2:ITO薄膜材料分析 36
5-3-1 SiO2:ITO之FTIR分析 37
5-3-2 SiO2:ITO之XPS分析 37
5-4 SiO2:ITO介面型態電阻式記憶體 37
5-4-1 元件基本特性 37
5-4-2 在不同截止電壓的特性 38
5-4-3 元件電流傳導機制擬合 38
5-4-4元件電流傳導機制模型 39
5-5 SiO2:ITO 阻絲型態電阻式記憶體 39
5-5-1 元件基本特性 40
5-5-2 元件電流傳導機制分析 40
5-5-3元件電流傳導機制模型 41
第六章 應用於互補式電阻切換之電阻式記憶體 57
6-1 實驗動機 57
6-2 互補式電阻切換之電阻式記憶體介紹 57
6-2-1 互補式電阻記憶體之操作 57
6-2-2互補式電阻記憶體存取與寫入 58
6-3元件介紹 58
6-4互補式電阻切換之電阻式記憶體I-V特性 59
6-4-1Pt / Hf:SiO2 / TiN 59
6-4-2 ITO / Hf:SiO2 / TiN 59
6-4-3 Pt / Hf:SiO2 / ITO / Hf:SiO2 / TiN 59
6-4-4 ITO / SiO2:ITO / TiN 60
6-5 Pt與ITO互補式RRAM比較 60
第七章 結論 71
參考文獻 72

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