電阻式記憶體(RRAM)是目前最熱門之次世代記憶體之一，其元件具有操作速度快，最小可微縮尺寸，高可靠性質等特點。其中RRAM簡單的結構體(金屬-氧化物-金屬)大大降低了入門難度，但最大難題來自於該如何選材，為了能使元件之製程可配合積體電路製程技術，因此我們選用二氧化矽為基礎材料進行研究。
超臨界二氧化碳流體為工業界最常使用之綠色溶劑，憑藉流體本身高穿透性與低表面張力之特性，可有效的清洗或是針對細微孔洞進行改質，因此研究超臨界流體對電阻式記憶體特性改質之效應為本實驗之重點。
本實驗以利用濺鍍方式引入鈦金屬摻雜至二氧化矽薄膜中成功使原本不具電阻切換特性之二氧化矽薄膜形成電阻式記憶體元件，同時利用超臨界二氧化碳流體夾帶溶質的方式，於高壓環境下對鈦摻雜之薄膜進行改質後，其薄膜依然具有電阻切換特性。其材料分析結果顯示，超臨界處理具有修補二氧化矽缺陷以及鈦的自身還原反應，這是之前所未遇過的結果，其中由水所引入之氫氧鍵，在薄膜內局部形成離子摻雜，使得元件切換特性具有介面現象。藉由定電壓的操作方式，我們可區分出三階段的離子反應速率與其反應活化能。
最後利用製程方式引入鈦摻雜與碳摻雜之雙層二氧化矽結構，利用碳核點不具氧化還原且為導體之特性，成功的使電子以跳躍(hopping)機制進行傳導，降低高低組態電流，在元件進行高限流操作時能夠達到限流之作用，透過電場模擬印證了Space-Charge Limited Current之傳導機制。

The resistance random access memory (RRAM) is one of the most popular of the next generation memories with the high operating speed, reliability and the smallest miniature size. RRAM has metal-insulator-metal structure that can greatly reduce the difficulty of entry, but the biggest problem is how to choose the insulator. We selected silicon-based materials to match the intergrated circuits manufacturing process.
In this work, sputtering titanium doping in the silicon oxide thin film has a stable characteristic of resistance switching. By material analyzing, we found that supercritical carbon dioxide fluid (SCCO2) treatment can passivate the silicon oxide defect and the self-reduction of titanium oxide, but it also brought OH group into our thin film. So we observed the interface type characteristic of resistance switching. Using constant voltage sampling experiment extract the reaction rate constant (k) and the active energy, prove that the reaction is caused by OH injection.
Double-layer structure with titanium-doped and carbon-doped silicon oxide RRAM promote lower operating current by hopping conduction, which is caused by graphite oxide doping. The Space-Charge Limited Current mechanism for high limited current is proven by COMSOL electric field simulation.

目錄
論文審定書 i
致謝 ii
中文摘要 iii
Abstract iv
目錄 v
圖目錄 viii
表目錄 xii
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
2-2-1 次世代記憶體簡介 4
2-2-2 鈦電阻式記憶體簡介 5
2-2 超臨界流體簡介 6
第三章 實驗設備與原理 13
3-1多靶磁控濺鍍系統( Multi-Target Sputter) 13
3-2 N & K薄膜特性分析儀(N & K analyzer) 13
3-3 傅立葉轉換紅外光譜儀 (Fourier-Transform Infrared Spectrometer) 14
3-4 X光光電子能譜儀(X-ray Photoelectron Spectroscopy) 15
3-5 半導體精準電性量測系統 16
3-6 光學微影系統 16
3-7 超臨界流體系統 17
第四章 實驗流程 22
4-1 RRAM元件基板準備 22
4-1-1 基板準備 22
4-1-2 基板清洗與切割 22
4-2 RRAM元件製備 22
4-2-1 RRAM 元件M-I-M層膜製作方法 22
4-2-2 二氧化矽薄膜製備 (SiO2 M-I-M元件) 23
4-2-3 鈦摻雜二氧化矽薄膜RRAM製備( Ti : SiO2 RRAM) 23
4-3 超臨界流體處理RRAM 備製 23
4-3-1 RRAM薄膜製備 23
4-3-2 超臨界流體處理 24
4-3-3 光阻覆蓋(黃光微影) 24
4-3-4 Pt 電極覆蓋 24
4-4 電性量測 24
4-5 材料分析 25
4-6 實驗流程大綱圖 26
第五章 鈦摻雜之二氧化矽電阻式記憶體 32
5-1 SiO2 M-I-M元件 分析 32
5-1-1 Forming分析 32
5-1-2 SiO2 M-I-M元件Set-Reset分析 32
5-2 Ti : SiO2 RRAM 分析 32
5-2-1 RF Power 10W之Ti : SiO2 RRAM 33
5-2-2 RF Power 5W之Ti : SiO2 RRAM 33
5-2-3 RF Power 5W之Ti : SiO2 RRAM 材料分析 33
5-2-4 定電流Forming法( Constant Current Forming )於Ti : SiO2 RRAM 探討 34
第六章 超臨界流體處理之鈦摻雜二氧化矽電阻式記憶體 53
6-1 超臨界處理(SCCO2+DI Water) Ti : SiO2 RRAM 分析 53
6-1-1超臨界處理(SCCO2+DI Water) Ti : SiO2 RRAM Forming 53
6-1-2超臨界處理(SCCO2+DI Water) Ti : SiO2 RRAM多種限流基本I-V圖 53
6-1-3 超臨界處理(SCCO2+DI Water) Ti : SiO2 RRAM 材料分析 54
6-2 超臨界處理前後 Ti : SiO2 RRAM電阻切換特性分析 55
6-2-1 超臨界二氧化碳流體處理前後之Forming與低阻態(LRS)分析 56
6-2-2 超臨界二氧化碳流體處理前後之高阻態(HRS)分析 56
6-2-3超臨界二氧化碳流體處理後之插入式RRAM (Insert RRAM)分析 57
6-3 第六章小結 59
第七章 超臨界處理之電阻式記憶體化學反應模型 73
7-1 定電壓操作對超臨界流體處理之Ti : SiO2 電阻式記憶體RESET過程分析 73
7-1-1 定電壓Reset對Ti : SiO2 RRAM 之分析 73
7-1-2 變溫定電壓Reset對Ti : SiO2 RRAM 之分析 74
7-2 定電流法萃取反應常數與活化能 75
第八章 鈦摻雜與碳摻雜雙層二氧化矽薄膜電阻式記憶體 84
8-1鈦摻雜與碳摻雜雙層二氧化矽薄膜電阻式記憶體製作 84
8-1-1 Pt/Ti : SiO2/C : SiO2/TiN RRAM 製作 84
8-1-2 碳摻雜二氧化矽薄膜材料分析 84
8-2鈦摻雜與碳摻雜雙層二氧化矽薄膜元件電性分析 85
8-2-1 單雙層元件限流500uA操作比較 85
8-2-2 Pt/Ti : SiO2/C : SiO2/TiN RRAM 限流10mA操作分析 85
第九章 結論 94
Reference 95

[1] S. Lai, “Non-Volatile Memory Technologies: The Quest for Ever Lower Cost”, International Electron Devices Meeting, pp. 11, 2008
[2] D. A. Buck, “Ferroelectrics for Digital Information Storage and Switching.”, Massachusetts Institute of Technology, Dept. of Electrical Engineering, Master Thesis, 1952.
[3] S. Lai, “Current status of the phase change memory and its future”, International Electron Devices Meeting Technical Digest, pp. 255 - 258, 2003.
[4] 葉林秀、李佳謀、徐明豐、吳德和， “磁阻式隨機存取記憶體技術的發展—現在與未來.”， 物理雙月刊， 26卷， pp. 607- 619， 2004。
[5] K. Kinoshita, T. Tamura, H. Aso, H. Noshiro, C. Yoshida, M. Aoki, Y. Sugiyama and H. Tanaka, “New Model Proposed for Switching Mechanisms of ReRAM”, Proceedings Non-Volatile Semiconductor Memory Workshop, pp. 84-85, 2006.
[6] S. Karg, G. Meijer, J. Bednorz, C. Rettner, A. Schrott, E. Joseph, C. Lam, M. Janousch, U. Staub, F. La Mattina, S. Alvarado, D. Widmer, R. Stutz, U. Drechsler and D. Caimi, “Transition-metal-oxide-based resistancechange memories”, IBM Journal of Research and Development, Vol. 52, No. 4/5, pp. 481-492, 2008.
[7] 鄭佩慈，“鐵電材料之特性與應用.”， 儀科中心簡訊，第68期， 2005。
[8] Moise et al. “Hardmask designs for dry etching FeRAM capacitor stacks”, US6534809, 2003
[9] K. Kim; S. J. Ahn “Reliability investigations for manufacturable high density PRAM”, Proc. IRPS, pp. 157, 2005
[10] G. Burr, B. Kurdi, J. Scott, C. Lam, K. Gopalakrishnan and R. Shenoy“Overview of candidate device technologies for storage-class memory”, IBM Journal of Research and Development, Vol. 52, No. 4/5, pp. 449-464, 2008.
[11] 廖國孝, “錫摻雜二氧化矽薄膜之電阻式記憶體特性研究.”， 國立中山大學，碩士論文， 2011。
[12] 董承瑋, “鋅摻雜二氧化矽薄膜電阻式記憶體之製作與硏究.”， 國立中山大學，碩士論文， 2011。
[13] 莊翔嵐, “超臨界流體處理鎳矽氧化物薄膜再電阻式記憶體之應用研究.”， 國立高雄應用科技大學，碩士論文， 2011。
[14] S. S. Sheu, et al. “Fast-Write Resistive RAM (RRAM) for Embedded Applications.”, IEEE Des. Test Comput., vol. 28, pp. 64-71, 2011.
[15] K. J. Lee, et al. “A 90 nm 1.8 V 512 Mb Diode-Switch PRAM With 266 MB/s Read Throughput.”, IEEE J. Solid-State Circuits, vol. 43, pp. 150-162, 2008.
[16] R. Takemura, et al. “A 32-Mb SPRAM With 2T1R Memory Cell, Localized Bi-Directional Write Driver and `1'/`0' Dual-Array Equalized Reference Scheme”, IEEE J. Solid-State Circuits, vol. 45, pp. 869-879, 2010.
[17] S. Dietrich, et al. “A Nonvolatile 2-Mbit CBRAM Memory Core Featuring Advanced Read and Program Control.”, IEEE J. Solid-State Circuits, Vol. 42, pp. 839-845, 2007.
[18] M. F. Chang, S. J. Shen, “A Process Variation Tolerant Embedded Split-Gate Flash Memory Using Pre-Stable Current Sensing Scheme”. J. Solid-State Circuits, vol. 44, pp. 987-994, 2009.
[19] Y. J. Hu, et al, “Role of Interface Reaction on Resistive Switching of Metal/Amorphous TiO2/Al RRAM Devices”, Journal of The Electrochemical Society, 158 (10) , pp. 979-982 ,2011
[20] Liang Zhao, Jinyu Zhang, Yu He, Ximeng Guan, He Qian, and Zhiping Yu, “Dynamic Modeling and Atomistic Simulations of SET and RESET Operations in TiO2-Based Unipolar Resistive Memor”, IEEE Electron Device Letters, Vol. 32, No. 5, 2011
[21] Y. L. Chung, P. Y. Lai, Y. C. Chen, and J. S. Chen,“Schottky Barrier Mediated Single-Polarity Resistive Switching in Pt Layer - Included TiOx Memory Device”, ACS Appl. Mater. Interfaces, 3(6), pp. 1918–1924, 2011.
[22] Z. Fang , et al.,”HfOx/TiOx/HfOx/TiOx Multilayer-Based Forming-Free RRAM Devices With Excellent Uniformity”, IEEE Electron Device Letters, Vol. 32, No. 4, 2011
[23] http://en.wikipedia.org/wiki/Supercritical_fluid
[24] V. Dostal, “A supercritical carbon dioxide cycle for next generation nuclear reactors”, Massachusetts Institute of Technology, Doctorate Dissertation, 2004.
[25] Edit Szekely, ”Supercritical Fluid Extraction”, Budapest University of Technology and Economics,2007.
[26] R. Waser, R. Dittmann, G. Staikov, & K. Szot, “Redox-Based Resistive Switching Memories - Nanoionic Mechanisms, Prospects, and Challenges”, Adv Mater , Vol. 21, pp. 2632, 2009.
[27] T. F. YOUNG, & C. P. CHEN, “Study on the Si Si Vibrational States of the Near Surface Region of Porous Silicon”, Journal of Porous Materials 7, pp. 339–343, 2000.
[28] L. P. XU, Y. X. ZHAO, Z. G. WU, D. S. LIU, “A New Method for Preparing Ti-Si Mixed Oxides”, Chinese Chemical Letters Vol. 14, No. 11, pp. 1159–1162, 2003.
[29] J. Su, G. Xiong, J. C. Zhou, W. H. Liu, D. H. Zhou, Guiru Wang, X. S. Wang, H. C. Guo, “Amorphous Ti species in titanium silicalite-1: Structural features, chemical properties, and inactivation with sulfosalt” Journal of Catalysis, Vol. 288, pp. 1–7, 2012.
[30] M. A. Ahmed, “Synthesis and structural features of mesoporous NiO/TiO2 nanocomposites prepared by sol–gel method for photodegradation of methylene blue dye”, Journal of Photochemistry and Photobiology A: Chemistry, Vol. 238, pp. 63– 70, 2012.
[31] Yao Sha, Ted H. Yu, Yi Liu, Boris V. Merinov,* and William A. Goddard III, “Theoretical Study of Solvent Effects on the Platinum-Catalyzed Oxygen Reduction Reaction”, The Journal of Physical Chemistry Letters, Vol. 1, pp. 856–861, 2010.
[32] C. E. Hamilton, PhD Thesis, Rice University, 2009