電阻式記憶體(RRAM)具有結構簡單，高密度，操作速度快，低消耗功率，穩定性高，資料保存能力好等優點，且其製程可與現金互補式金屬氧化物半導體(CMOS)製程技術相容，本論文探討以氮化鈦(TiN)/鈦(Ti)/氧化鉿(HfO2)/氮化鈦(TiN)結構為主的電阻式記憶體，在上電極與介電層中增加了一層鈦，做為氧離子收集層，以提升元件電阻阻態轉換特性。本文探討其操作面積，介電層厚度，熱退火溫度，熱退火時間，對於元件的特性影響。元件製備完後，此外在量測時經由限制電流與電壓的改變，使元件具備多種電阻阻態的轉換。經由熱退火改變氧空缺的分布，在電阻轉換部分更穩定，高低電阻阻態比更優良使元件電阻轉換特性更良好。
經由本文研究，氧化鉿基底電阻式記憶體經由四百度熱退火五分鐘，擁有良好的特性，其耐久度可達到1012次以上，操作電壓小於1V，高低阻態(ON/OFF ratio)比大於102，具備穩定性高，且資料保存能力好等優點，因此具有發展潛力。

The resistive RAM has advantages of simple structure, high density, fast switching speed, low power operation, and reliable retention. Furthermore, some RRAMs are friendly for CMOS integration. Thus, RRAM has a great potential as mainstream memories in the future.
In this thesis, TiN/Ti/HfO2/TiN RRAM structure was fabricated and studied. Thin Ti layer was inserted between top electrode and hafnium oxide, which can absorb oxygen atoms from dielectric layer. This Ti layer can greately enhance the performance of the RRAM by serving as an oxygen reservoir to fullfill the supply and demand of oxygen in HfO2 layer. The effects of four experiment structure and process parameters on the performance of RRAM were studied in this thesis: active region size、thickness of dielectric layer、annealing temperature、annealing time. The annealing temperature and time plays an ctitica role in this device fabrication.
The layer structure of Resistive RAM device studied in this thesis was TiN/Ti/HfO2/TiN, with Ti thickness of 10 nm and HfO2 thickness of 10 nm. By applying post metal annealing at 500⁰C for 4 minutes, RRAM with low operation voltage (<1V), reliable switching endurance (>10^6cycles), high ON/OFF ratio (>10^2) ,and good retention(>5×10^4s) can be achieved.

[1]楊瑞臨,彭茂榮. "下世代記憶體技術趨勢與全球競合分析", 2011.
[2] H. Kyder, M., C.S. Kim, "After Hard Drives - What Comes Next?", IEEE Transactions on Magnetics., vol. 45, 2009.
[3] J. H. Oh, et al.,"Full integration of highly manufacturable 512 Mb PRAM based on 90 nm technology", IEEE International Electron Device Meeting., pp. 1-4, 2006.
[4] S. Lai, T. Lowrey, "OUM - A 180 nm nonvolatile memory cell element technology for stand alone and embedded applications", IEEE International Electron Device Meeting., pp. 36.5.1 - 36.5.4, 2001.
[5] S. Tehrani,"Status and Outlook of MRAM Memory Technology", IEEE International Electron Device Meeting., pp.1-4, 2006.
[6] K. Amanuma, T. Tatsumi, Y. Maejima, S. Takahashi, H. Hada, H. Okizaki, T. Kunio, "Capacitor-on-Metal/Via-stacked-Plug (CMVP) Memory Cell for 0.25 um CMOS Embedded FeRAM", IEEE International Electron Device Meeting., pp.363-366, 1998.
[7] C. Cagli, et al., "Experimental and Theoretical Study of Electrode Effects in HfO2 based RRAM", IEEE International Electron Device Meeting., pp.28.7.1-28.7.4, 2011.
[8] S.Q. Liu, N.J. Wu, A. Ignatiev, "Electric-pulse-induced reversible resistance change effect in magnetoresistive films", Applied Physics Letters., vol.76, pp. 2749 - 2751, 2000.
[9] U. Russo, D. Ielmini , C. Cagli, A. L. Lacaita, S. Spigat, C. Wiemer. M. Perego, M. Fanciulli, "Conductive-filament switching analysis and self-accelerated thermal dissolution model for reset in NiO-based RRAM", IEEE International Electron Device Meeting., pp.775-778, 2007.
[10]00Y.C. Huang, H.M. Lin., H.C. Cheng., "Superior resistive switching characteristics of Cu-TiO2 based RRAM cell", INEC., pp.236-239, 2013.
[11]00Q. Lv, et al., "Conducting nanofilaments formed by oxygen vacancy migration in Ti/TiO2/TiN/MgO memristive device", Applied Physics Letters., vol. 110, pp. 104511, 2001.
[12]00Y. Li, "Reset Instability in Cu/ZrO2:Cu/Pt RRAM Device", IEEE Electron Device Letters., vol. 32, 2011.
[13] H.B. Lv, et al., "Forming Process Investigation of CuxO Memory Films", IEEE Electron Device Letters., vol. 29, pp. 47 - 49, 2008,
[14] Y.S. Chen, H.Y. Lee., P.S. Chen., W.S. Chen., K.H. Tsai., P.Y. Gu., T.Y. Wu., C.H. Tsai., S.Z. Rahaman., Y.D. Lin., F. Chen., M.J. Tsai., T.K. Ku., "Novel Defects-Trapping TaOX/HfOX RRAM With Reliable Self-Compliance, High Nonlinearity, and Ultra-Low Current", IEEE Electron Device Letters., vol. 35, pp. 202-204, 2013.
[15] Y.S. Chen, H.Y. Lee., P.S. Chen., W.H. Liu., S.M. Wang., P.Y. Gu., Y.Y. Hsu., C.H. Tsai., W.S. Chen., F. Chen., M.J. Tsai., Chenhsin Lien, "Robust High-Resistance State and Improved Endurance of HfOX Resistive Memory by Suppression of Current Overshoot", IEEE Electron Device Letters., vol. 32, pp.1585-1587, 2011.
[16] Y.Y. Chen, R. Degraeve., B. Govoreanu., S. Cilma., L. Goux., A. Fantini., G.S. Kar., D.J. Wouters., G. Groeseneken., M, Jurczak., "Postcycling LRS Retention Analysis in HfO2/Hf RRAM 1T1R Device", IEEE Electron Device Letters., vol. 34, pp.626-628, 2013.
[17] W. Liu., X.A.Tran., Z. Fang., H.D. Xiong,H.Y. Yu., "A Self-Compliant One-Diode-One-Resistor Bipolar Resistive Random Access Memory for Low Power Application", IEEE Electron Device Letters., vol.35, pp.196-198, 2014.
[18] H.Y. Lee., P.S. Chen., T.Y. Wu., Y.S. Chen., C.C. Wang., P.J. Tzeng., C.H. Lin., F. Chen., C.H. Lien., M.J. Tsai., "Low power and high speed bipolar switching with a thin reactive Ti buffer layer in robust HfO2 based RRAM", IEEE Electron Devices Meeting., pp. 1 - 4, 2008.
[19] I.G. Baek., et al., "Multi-layer cross-point binary oxide resistive memory (OxRRAM) for post-NAND storage application", IEEE Electron Devices Meeting., pp. 750 - 753, 2005.
[20] Akinaga, H., H. Shima., "Resistive Random Access Memory (ReRAM) Basedon Metal Oxides", Proceedings of the IEEE., pp. 2237-2251, 2010.
[21] D. C. Kim., M.J.Lee., S. E. Ahn, S. Seo., J. C. Park., I. K. Yoo., I. G. [21]Baek., H.J. Kim., E.K. Yim., J. E. Lee., S. O. Park., H. S. Kim., U–In [21]Chung., J. T. Moon., B.I. Ryu., "Improvement of resistive memory [21]switching in NiO using IrO2", in Applied Physics Letters., vol. 88, [21]pp.232106-232106-3, 2006.
[22] C. Park, S.H.Jeon., S. C. Chae., S. Han., B. H. Park., S. Seo., D.W. Kim., "Role of structural defects in the unipolar resistive switching characteristics of Pt/NiO/Pt structures", Applied Physics Letters., vol. 93, pp. 042102, 2008.
[23] Y. Sakotsubo., M. Terai., S. Kotsuji., Y. Saito., M. Tada., Y. Yabe., H. Hada., "A new approach for improving operating margin of unipolar ReRAM using local minimum of reset voltage", VLSI Technology., pp. 87-88, 2010.
[24] L.F. Liu., J.F. Kang., N. Xu., Xiao Sun., C. Chen., S. Bing., Y. Wang., X.Y. Liu., X. Zhang., R.Q. Han., "Gd Doping Improved Resistive Switching Characteristics of TiO2-Based Resistive Memory Devices", Applied Physics Letter, pp. 2901, 2008.
[25] J.S. Kwak., Y.H. Do., Y.C. Bae., H.S. Im., Jong Hee Yoo, Min Gyu Sung, Y.T. Hwang., J.P. Hong., "Roles of interfacial TiOxN1-x layer and TiN electrode on bipolar resistive switching in TiN/TiO2/TiN frameworks", Applied Physics Letters., vol. 96, pp. 223502-223502-3, 2010.
[26] Dongsoo Lee, et al., "Excellent uniformity and reproducible resistance switching characteristics of doped binary metal oxides for non-volatile resistance memory applications", IEEE Electron Devices Meeting., pp. 1-4, 2006.
[27] Y.Y. Chen., M. Komura, R. Degraeve., "Improvement of data retention in HfO2 / Hf 1T1R RRAM cell under low operating current", IEEE Electron Devices Meeting., pp. 10.1.1-10.1.4, 2013.
[28] Lien, C.H.,Y.S. Chen., H.Y. Lee., P.S. Chen., F.T. Chen., M.J. Tsai., "The Highly Scalable and Reliable Hafnium Oxide ReRAM and Its Future Challenges", Solid-State and Integrated Circuit Technology., pp. 1084-1087, 2010.
[29] C.H. Wang., et al., "Three-Dimensional 4F2 ReRAM Cell with CMOS Logic Compatible Process", IEEE Electron Devices Meeting., vol. 58., pp. 29.6.1 - 29.6.4., 2010.
[30] P.S. Chen., H.Y. Lee., Y.S. Chen., Frederick Chen., M.J. Tsai., "Improved Bipolar Resistive Switching of HfOx/TiN Stack with a Reactive Metal Layer and Post Metal Annealing"., Applied Physics Letter, vol. 49, pp. 04DD18-04DD18-5, 2010.
[31] P. Pavan., R. Bez., P. Olivo., E. Zanoni., "Flash Memory Cells - an Overview"., in Proceedings of the IEEE., vol. 85, pp. 1248-1271, 1997.
[32] FUJITSU., "What's FRAM"., 2005,
http://www.fujitsu.com/cn/fsp/tw/memory/fram/overview/.
[33] R. Waser., M. Aono., "Nanoionics-based resistive switching memories", Nature Materials., 2007.
[34] Sawa, A., "Reistive switching in transition metal oxides", Materials Today., pp. 28-36., 2008.
[35] R. Waser., "Electrochemical and thermochemical memories", IEEE Electron Devices Meeting., pp. 1-4., 2008.
[36] H. Yu., Jinyu Zhang., X. Guan., Z. Liang., W. Yan., Q. He., Y. Zhiping., " Molecular Dynamics Study of the Switching Mechanism of Carbon-Based Resistive Memory", IEEE Transactions on Electron Devices., vol. 57, pp. 3434-3441, 2010.
[37] H.Y. Lee., Y.S. Chen., P.S. Chen., T.Y. Wu., F. Chen., C.C. Wang., P.J. Tzeng., M.J. Tsai., C. Lien., "Low-Power and Nanosecond Switching in Robust Hafnium Oxide Resistive Memory With a Thin Ti Cap", IEEE Electron Device Letters, vol. 31., pp. 44-46., 2010.