本論文中，內容著重在於氧化鋅電阻式記憶體的改善以及應用。所有電阻式記憶體元件皆由氧化鋅為主要材料，且皆由原子層化學氣相沉積法與磁控濺鍍系統製備。
論文一開始將針對非揮發性記憶體進行簡單的介紹，包含各式的記憶體的應用，同時也簡述了本論文將對氧化鋅這材料進行研究之動機。接著回顧電阻式記憶體之現況，此部分亦統整了一些已被發表的重要效應與電阻轉換機製，如所使用的材料、電阻式記憶體的特性以及電阻轉換機制等，在文中將作進一步地解說。而第三章說明了本論文的實驗細節、元件的製作流程、材料分析原理與相關之電性量測等，論文中之研究結果均是在藉由這一連串的步驟所得到的。
四、五兩章節將呈現本論文核心內容。第四章敘述了利用原子層化學氣相沉積法配合感應耦合電漿進行氧化鋅薄膜的改質，藉此去深入探討氧化鋅薄膜的電性、材料性質與成長機製的關係，同時利用電漿改質的方法可有效改善其表面披覆的能力與增加其在電阻式記憶體上應用之可能性。而第五章將討論利用通氧量的不同來改善氧化鋅電阻式記憶體之穩定性。結果發現在濺鍍過程中通入少量的氧氣可穩定氧化鋅電阻式記憶體，此穩定的結果是受材料中微結構的改變與缺陷的影響所致。文章第六章部分將結合第四與第五章，利用兩種製程連續沉積氧化鋅雙層結構之電阻轉換元件，其結果顯示了非線性之電阻轉換特性，此特性將有助於解決在應用於交疊排列之矩陣電路時發生的短路現象。而文章最後一部分再對本文進行總結與建議。

In this thesis, we focus on improvement of ZnO-based resistive random access memory (RRAM) researches. ZnO was a main material prepared by the atomic-layer-deposition (ALD) and magnetic sputtering technique for RAM devices.
In the first part, inductively coupled plasma technique (ICP), namely, remote-plasma treatment was used to ionize the water molecules in order to improve the deposition of ZnO film via the atomic layer deposition processes. The relationship between resistivity and formation mechanisms have been discussed and investigated through analyses of atomic force microscopy, photonluminescence, and absorption spectra, respectively. Findings indicate that the steric hindrance of the ligands plays an important rule for the ALD-ZnO film sample with the ICP treatment while the limited number of bonding sites will be dominant for the ALD-ZnO film without the ICP treatment owing to a decrease of the reactive sites via the ligand-exchange reaction during the dissociation process. Finally, the enhanced aspect-ratio into the anodic aluminum oxide with the better improved uniform coating of ZnO layer after the ICP treatment was demonstrated, providing an important information for a promising application in electronics based on ZnO ALD films.
In the second part, a stability scheme of resistive switching devices based on ZnO films deposited by radio frequency (RF) sputtering at different oxygen pressure ratios. I-V measurements and statistical results indicate that operating stability of ZnO ReRAM devices is highly dependent of the oxygen conditions. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) of ZnO at different O2 pressure ratios were investigated to reflect influence of structure to the stable switching behaviours. In addition, PL and XPS results were measured to investigate different charge states triggered in ZnO by oxygen vacancies, which affect the stability of the switching behavior.
In the final part, we combined the concept of the first and the second research to fabricate a bi-layer structure ZnO RRAM device. A non-linear behavior was observed in a small operating condition region. The results should be the solution to solve the sneak path problem in the cross-bar array RRAM application.

Chapter 1

D. Kahng and S. M. Sze, “A floating gate and its application to memory devices.” Bell Syst. Tech. J., vol. 46, p. 1288, 1967.
S. M. Sze and Kwok K. Ng, Physics of Semiconductor Devices, 3rd ed. New York: Wiley, 2007.
K. Kim, J. H. Choi and H. -S. Jeong, “The future prospect of nonvolatile memory,” in Proc. VLSI-TSA-Tech., p. 88, 2005.
R. Bez and A. Pirovano, “Non-volatile memory technologies: emerging concepts and new materials.” Materials Science in Semiconductor Processing, vol. 7, p. 349, 2004.
R. Waser, “Nanoelectronics and information technology.” Wiley VCH
R. Sbiaa, H. Meng and S. N. Piramanayagam, “Materials with perpendicular magnetic anisotropy for magnetic random access memory.” Phys. Status Solidi RRL, vol. 5, p. 413, 2011.
S. Lai and T. Lowrey, “OUM - a 180 nm nonvolatile memory cell element technology for stand alone and embedded applications.” in IEDM Tech. Dig., p. 803, 2001.
I. T. Drapak, “Visible luminescence of a ZnO–Cu2O heterojunction.” Fizika i Tekhnika Poluprovodnikov, vol. 2, p. 614, 1968.
A. Tsukazaki, A. Ohtomo, T. Onuma, M.Ohtani, T. Makino, M. Sumiya, K.Ohtani, S. F. Chichibu, S. Fuke, Y. Segawa, H. Ohno, H. Koinuma and M. Kawasaki, “Repeated temperature modulation epitaxy for p-type doping and light-emitting diode based on ZnO.” Nature Mater., vol. 4, p. 42, 2005.
A. Tsukazaki, M. Kubota, A. Ohtomo, T.Onuma, K.Ohtani, H.Ohno, S.F.Chichibu, and M. Kawasaki, B “Blue light-emitting diode based on ZnO.” Jpn. J. Appl. Phys., vol. 44, p. L643, 2005.
Ü. Özgür, D. Hofstetter and H. Morkoc “ZnO devices and applications: A review of current status and future prospects.” Proceedings of the IEEE, vol. 98, p. 1255, 2010.
D. G. Thomas, “The exciton spectrum of zinc oxide.” J. Phys. Chem. Solids, vol. 15, p. 86, 1960.
A. Mang, K. Reimann and St. Rübenacke, “Band gaps, crystal-field splitting, spin-orbit coupling, and exciton binding energies in ZnO under hydrostatic pressure.” Solid State Commun., vol. 94, p. 251, 1995.
D. C. Reynolds, D. C. Look, B. Jogai, C. W. Litton, G. Cantwell and W. C. Harsch, “Valence-band ordering in ZnO.” Phys. Rev. B, vol. 60, p. 2340, 1999.
Y. Chen, D. M. Bagnall, H. J. Koh, K. T. Park, K. Hiraga, Z. Q. Zhu and T. Yao, “Plasma assisted molecular beam epitaxy of ZnO on c -plane sapphire: Growth and characterization.” J. Appl. Phys., vol. 84, p. 3912, 1998.
M. Leskelä and M. Ritala, “Atomic layer deposition (ALD): from precursors to thin film structures.” Thin Solid Films, vol. 409, p.138, 2002.
W. Y. Chang, Y. C. Lai, T. B. Wu, S. F. Wang, F. Chen and M. J. Tsai, “Unipolar resistive switching characteristics of ZnO thin films for nonvolatile memory applications.” Appl. Phys. Lett., vol. 92, p. 022110, 2008.
Y. C. Yang, F. Pan, Q. Liu, M. Liu and F. Zeng, “Fully room-temperature-fabricated nonvolatile resistive memory for ultrafast and high-density memory application.” Nano Lett., vol. 9, p. 1636, 2009.
L. M. Kukreja, A. K. Das and P. Mishra, “Studies on nonvolatile resistance memory switching in ZnO thin films.” Bull. Mater. Sci., vol. 32, p. 247, 2009.
S. Kim, H. Moon, D. Gupta, S. Yoo and Y. K. Choi, “Resistive switching characteristics of sol–gel zinc oxide films for flexible memory applications.” IEEE Trans. Electron Devices, vol. 56, p. 696, 2009.

Chapter 2

T. Prodromakis, C. Toumazou and L. Chua, “Two centuries of memristors.” Nat. Mater., vol. 11, p. 478, 2012.
L. O. Chua, "Memristor-missing circuit element", IEEE Trans. Circuit Theory, Vol. 18, p. 507, 1971.
T. W. Hickmott, “Low‐frequency negative resistance in thin anodic oxide films.” J. Appl. Phys., vol. 33, p. 2669, 1962.
J. G. Simmons and R. R. Verderber, “New conduction and reversible memory phenomena in thin film insulating films.” Proc. R. Soc. A., vol. 301, p. 77, 1967.
G. Dearnaley, A. M. Stoneham, and D. V. Morgan, “Electrical phenomena in amorphous oxide films.” Rep. Prog. Phys., vol. 33, p. 1129, 1970.
B. J. Choi, D. S. Jeong, S. K. Kim, C. Rohde, S. Choi, J. H. Oh, H. J. Kim, and C. S. Hwang, K. Szot and R. Waser, B. Reichenberg and S. Tiedke, “Resistive switching mechanism of TiO2 thin films grown by atomic-layer deposition,” J. Appl. Phys., vol. 98, pp. 033715, 2005.
W. W. Zhuang, W. Pan, B. D. Ulrich, J. J. Lee, L. Stecker, A. Burmaster, D. R. Evans, S. T. Hsu, M. Tajiri, A. Shimaoka, K. Inoue, T. Naka, N. Awaya, K. Sakiyama, Y. Wang, S. Q. Liu, N. J. Wu and A. Iganatiev, “Novell colossal magnetoresistive thin film nonvolatile resistance random access memory (RRAM),” in IEDM Tech. Dig., p. 193, 2002.
D. B. Strukov, G. S. Snider, D. R. Stewart and R. S. Williams, “The missing memristor found,” Nature, vol. 453, p.80, 2008.
F. Zhuge, B. Hu, C. He, X. Zhou, Z. Liu and R. W. Li, “Mechanism of nonvolatile resistive switching in graphene oxide thin films,” Carbon, vol. 49, p.3796, 2011.
H. Wang, F. Meng, Y. Cai, L. Zheng, Y. Li, Y. Liu, Y. Jiang, X. Wang and X. Chen, “Sericin for resistance switching device with multilevel nonvolatile memory,” Adv. Mater., vol. 28, p. 5498, 2013.
M. N. Kozicki and M. Mitkova, “Mass transport in chalcogenide electrolyte films – materials and applications,” J. Non-Cryst. Solids, vol. 352, p. 567, 2006.
D. H. Kwon, K. M. Kim, J. H. Jang, J. M. Jeon, M. H. Lee, G. H. Kim, X. S. Li, G. S. Park, B. Lee, S. Han, M. Kim and C. S. Hwang, “Atomic structure of conducting nanofilaments in TiO2 resistive switching memory,” Nat Nano., vol. 5, p. 148, 2010.
J. P. Strachan, M. D. Pickett, J. J. Yang, S. Aloni, A. L. David Kilcoyne, G. Medeiros-Ribeiro and R. Stanley Williams, “Direct identification of the conducting channels in a functioning memristive device,” Adv. Mater., vol. 22, p. 3573, 2010.
R. Waser, R. Dittmann, G. Staikov and K. Szot, “Redox-based resistive switching memories – nanoionic mechanisms, prospects, and challenges,” Adv. Mater., vol. 21, p. 2632, 2009.
S. B. Lee, H. K. Yoo, K. Kim, J. S. Lee, Y. S. Kim, S. Sinn, D. Lee, B. S. Kang, B. Kahng and T. W. Noh, “Forming mechanism of the bipolar resistance switching in double-layer memristive nanodevices,” Nanotechnology, vol. 23, p. 315202, 2012.
J. S. Lee and B. Kahng, “Scaling behaviors of the voltage distribution in dielectric breakdown networks,” Phys. Rev. E, vol. 83, p. 052103, 2011.
J. Joshua Yang, F. Miao, M. D. Pickett, D. A. A. Ohlberg, D. R Stewart, C. N. Lau and R. S. Williams, “The mechanism of electroforming of metal oxide memristive switches,” Nanotechnology, vol. 20, p. 215201, 2009.
K. Kinoshita, T. Tamura, M. Aoki, Y. Sugiyama and H. Tanaka, “Bias polarity dependent data retention of resistive random access memory consisting of binary transition metal oxide,” Appl. Phys. Lett., vol. 89, p. 103509, 2006.
K. M. Kim, B. J. Choi and C. S. Hwang, “Localized switching mechanism in resistive switching of atomic-layer-deposited TiO2 thin films,” Appl. Phys. Lett., vol. 90, p. 242906, 2007.
U. Russo, D. Ielmini, C. Cagli and A. L. Lacaita, “Self-accelerated thermal dissolution model for reset programming in unipolar resistive-switching memory (RRAM) devices,” IEEE Trans. Electron Devices, vol. 56, p. 193, 2009.
U. Russo, S. Member, D. Ielmini, C. Cagli, A. L. Lacaita and S. Member, “Filament conduction and reset mechanism memory in NiO-based resistive-switching (RRAM) devices,” IEEE Trans. Electron Devices, vol. 56, p. 186, 2009.
A. Sawa, “Resistive switching in transition metal oxides,” Mater. Today, vol. 11, p. 28, 2008.
A. Baikalov, Y. Q. Wang, B. Shen, B. Lorenz, S. Tsui, Y. Y. Sun, Y. Y. Xue and C. W. Chu, “Field-driven hysteretic and reversible resistive switch at the Ag-Pr0.7Ca0.3MnO3 interface,” Appl. Phys. Lett., vol. 83, p. 957, 2003.
S. Tsui, A. Baikalov, J. Cmaidalka, Y. Y. Sun, Y. Q. Wang, Y. Y. Xue, C. W. Chu, L. Chen, and J. Jacobson, “Field-induced resistive switching in metal-oxide interfaces,” Appl. Phys. Lett., vol. 85, p. 317, 2004.
X. Chen, N. J. Wu, J. Strozier and A. Ignatiev, “Direct resistance profile for an electrical pulse induced resistance change device,” Appl. Phys. Lett., vol. 87, p. 233506, 2005.
A. Sawa, T. Fujii, M. Kawasaki and Y. Tokura, “Hysteretic current-voltage characteristics and resistance switching at a rectifying Ti/Pr0.7Ca0.3MnO3 interface,” Appl. Phys. Lett., vol. 85, p. 4073, 2004.
T. Fujii, M. Kawasaki, A. Sawa, H. Akoh, Y. Kawazoe, and Y. Tokura, “Hysteretic current-voltage characteristics and resistance switching at an epitaxial oxide schottky junction SrRuO3/SrTi0.99Nb0.01O3,” Appl. Phys. Lett., vol. 86, p. 012107, 2005.
R. Fors, S. Khartsev, and A. Grishin, “Giant resistance switching in metal-insulator-manganite junctions: Evidence for Mott transition,” Phys. Rev. B, vol. 71, p. 1, 2005.
M. J. Rozenberg, I. H. Inoue, and M. J. Sánchez, “Strong electron correlation effects in nonvolatile electronic memory devices,” Appl. Phys. Lett., vol. 88, p. 033510, 2006.
J. Joshua Yang, Dmitri B. Strukov and Duncan R. Stewart, “Memristive devices for computing,” Nat. nano., vol. 8, p. 13, 2013.
G. T. Wright, “Mechanisms of space-charge-limited current in solids,” Solid-State Electron., vol. 2, p. 165, 1961.
J. G. Simmons, “Poole-Frenkel effect and Schottky effect in metal-insulator-metal systems,” Phys. Rev., vol. 155, p. 657, 1967.
P. R. Emtage and W. Tantraporn, “Schottky emission through thin insulating films,” Phys. Rev. Lett., vol. 8, p. 267, 1962.
N. M. Ravindra and J. Zhao, “Fowler-Nordheim tunneling in thin SiO2 films,” Smart Mater. Struct., vol. 1, p. 197, 1992.
E. Linn, R. Rosezin, C. Kugeler and R. Waser, "Complementary resistive switches for passive nanocrossbar memories", Nat. Mater., vol. 9, p. 403, 2010.
Z. J. Liu, J. Y. Gan and T. R. Yew, “ZnO-based one diode-one resistor device structure for crossbar memory applications” Appl. Phys. Lett., vol. 100, p. 153503, 2012.
M. J. Lee, Y. Park, B. S. Kang, S. E. Ahn, C. Lee, K. Kim, W. Xianyu, G. Stefanovich, J. H. Lee, S. J. Chung, Y. H. Kim, C. S. Lee, J. B. Park, I. G. Baek and I. K. Yoo, “2-stack ID-IR cross-point structure with xxide diodes as Switch elements for high density resistance RAM applications,” in IEDM Tech. Dig., p. 771, 2007.

Chapter 3

Picosun,“http://www.picosun.com.”[Online].Available:http://www.picosun.com.

Chapter 4

R. L. Hoffman, B. J. Norris and J. F. Wager, “ZnO-based transparent thin-film transistors,” Appl. Phys. Lett., vol. 82, p. 733, 2003.
S. K. Hazra and S. Basu, “ZnO p–n junctions produced by a new route,” Solid State Electron., vol. 49, p. 1158, 2005.
S. Mayer and K. L. Chopra, “Indium-doped zinc oxide films as transparent electrodes for solar cells,” Sol. Energy Mater., vol. 17, p. 319, 1988.
S. J. Pearton and D. P. Norton, K. Ip and Y. W. Keo, “Recent advances in processing of ZnO,” J. Vac. Sci. Technol. B, vol. 22, p. 932, 2004.
W. Y. Chang, Y. C. Lai, T. B. Wu, S. F. Wang, F. Chen and M. J. Tsai, “Unipolar resistive switching characteristics of ZnO thin films for nonvolatile memory applications.” Appl. Phys. Lett., vol. 92, p. 022110, 2008.
C. Platzer-Bjo ̈rkman, J. Lu, J. Kessler and L. Stolt, “Interface study of CuInSe2/ZnO and Cu(In,Ga)Se2/ZnO devices using ALD ZnO buffer layers,” Thin Solid Films, vol. 431-432, p. 321, 2003.
E. B. Yousfi, B. Weinberger, F. Donsanti, R. Cowache and D. Lincot, “Atomic layer deposition of zinc oxide and indium sulfide layers for Cu(In,Ga)Se2 thin-film solar cells,” Thin Solid Films, vol. 387, p. 29, 2001.
"U" ̈. O ̈zgu ̈r, Y. I. Alivov, C. Liu, A. Teke, M. A. Reshchikov, S. Dog ̌an, V. Avrutin, S. J. Cho and H. Morkoc, “A comprehensive review of ZnO materials and devices,” J. Appl. Phys., vol. 98, p. 041301, 2005.
J. H. Choi, Y. Mao and J. P. Chang, “Development of hafnium based high-k materials—A review,” Materials science & engineering R-reports, vol. 72, p. 97, 2011.
N. Nepal, N. Y. Garces, D. J. Meyer, J. K. Hite, M. A. Mastro and C. R. Eddy, “Assessment of GaN Surface Pretreatment for Atomic Layer Deposited High-k Dielectrics,” Appl. Phys. Express, vol. 4, p. 055802, 2011.
M. H. Lin, C. H. Hou, J. Y. Wu and T. B. Wu, “Thermal Stability Improvement via Cyclic D2O Radical Anneal Interposed in Atomic Layer Deposition Process,” J. Electrochem. Soc., vol. 158, p. H221, 2011.
C. C. Lien, C. Y. Wu, Z. Q. Li and J. J. Lin, “Electrical conduction processes in ZnO in a wide temperature range 20–500 K,” J. Appl. Phys., vol. 110, p. 063706, 2011.
H. Endo, T. Chiba, K. Meguro, K. Takahashi, K. Fujisawa, S. Sugimura, S. Narita, Y. Kashiwaba and E. Sato, “Fabrication and characterization of a ZnO X-ray sensor using a high-resistivity ZnO single crystal grown by the hydrothermal method,” Nucl. Instrum. Meth. A, vol. 665, p. 15, 2011.
M. Girtan, M. Kompitsas, R. Mallet and I. Fasaki, “On physical properties of undoped and Al and In doped zinc oxide films deposited on PET substrates by reactive pulsed laser deposition,” Eur. Phys. J-Appl. Phys., vol. 51, p. 33212, 2010.
L. I. Burova, N. S. Perov, A. S. Semisalova, V. A. Kulbachinskii, V. G. Kytin, V. V. Roddatis, A. L. Vasiliev, A. R. Kaul, Thin Solid Films 520, 4580 (2012).
S. O'Brien, M. Çopuroglu, P. Tassie, M. G. Nolan, J. A. Hamilton, I. Povey, L. Pereira, R. Martins, E. Fortunato and M. E. Pemble. “Effect of the nanostructure on room temperature ferromagnetism and resistivity of undoped ZnO thin films grown by chemical vapor deposition,” Thin Solid Films, vol. 520, p. 1174, 2011.
Zinc Oxide Bulk, Thin Films and Nanostructures (Eds: C. Jagadish, S. J. Pearton), Elsevier’s Science & Technology Rights, Netherlands 2006.
N. Huby, S. Ferrari, E. Guziewicz, M. Godlewski and V. Osinniy, “Electrical behavior of zinc oxide layers grown by low temperature atomic layer deposition,” Appl. Phys. Lett., vol. 92, p. 023502, 2008.
D. H. Levy and S. F. Nelson, “Thin-film electronics by atomic layer deposition,” J. Vac. Sci. Technol. A, vol. 30, p. 018501, 2012.
S. J. Lim, S. Kwon and H. Kim, “ZnO thin films prepared by atomic layer deposition and rf sputtering as an active layer for thin film transistor,” Thin Solid Films, vol. 516, p. 1523, 2008.
H. Makino, A. Miyake, T. Yamada, N. Yamamoto and T. Yamamoto, “Influence of substrate temperature and Zn-precursors on atomic layer deposition of polycrystalline ZnO films on glass,” Thin Solid Films, vol. 517, p. 3138, 2009.
S. Lee, S. Bang, J. Park, S. Park, W. Jeong and H. Jeon, “The effect of oxygen remote plasma treatment on ZnO TFTs fabricated by atomic layer deposition,” Phys. Status Solidi A, vol. 207, p. 1845, 2010.
M. Godlewski, E. Guziewicz, G. Luka, T. Krajewski, M. Lukasiewicz, L. Wachnicki, A. Wachnicka, K. Kopalko, A. Sarem and B. Dalati, “ZnO layers grown by Atomic Layer Deposition: A new material for transparent conductive oxide,” Thin Solid Films, vol. 518, p. 1145, 2009.
S. H. K. Park, C. S. Hwang, H. Y. Jeong, H. Y. Chu and K. I. Cho, “Transparent ZnO-TFT Arrays Fabricated by Atomic Layer Deposition,” Electrochem. Solid-State Lett., vol. 11, p. H10, 2008.
D. A. Mourey, D. A. L. Zhao, J. Sun and T. N. Jackson, “Fast PEALD ZnO Thin-Film Transistor Circuits,” IEEE Trans. Electron Devices, vol. 57, p. 530, 2010.
R. L. Puurunen, “Growth per cycle in atomic layer deposition: A theoretical model,” Chem. Vap. Deposition, vol. 9, p. 249, 2003.
E. Guziewicz, I. A. Kowalik, M. Godlewski, K. Kopalko, V. Osinniy, A. Wójcik, S. Yatsunenko, E. Łusakowska, W. Paszkowicz and M. Guziewicz, “Extremely low temperature growth of ZnO by atomic layer deposition,” J. Appl. Phys., vol. 103, p. 033515, 2008.
Steven M. George, “Atomic layer deposition: An overview,” Chem. Rev., vol. 110, p. 111, 2010.
D. H. Zhang and H. L. Ma, “Scattering mechanisms of charge carriers in transparent conducting oxide films,” Appl. Phys. A, vol. 62, p. 487, 1996.
S. Bandyopadhyay, G.K. Paul, R. Roya, S.K. Sen and S. Sen, “Study of structural and electrical properties of grain-boundary modified ZnO films prepared by sol–gel technique,” Mater. Chem. Phys., vol. 74, p. 83, 2002.
J. He, J. Liu, J. Hu, R. Zeng and W. Long, “Non-uniform ageing behavior of individual grain boundaries in ZnO varistor ceramics,” J. Eur. Ceram. Soc., vol. 31, p. 1451, 2011.
F. Oba, S. R. Nishitani, S. Isotani, H. Adachi and I. Tanaka, “Energetics of native defects in ZnO,” J. Appl. Phys., vol. 90, p. 824, 2001.
J. H. Lee, K. H. Ko and B. O. Park, “Electrical and optical properties of ZnO transparent conducting films by the sol–gel method,” J. Cryst. Growth, vol. 247, p. 119, 2003.
E. Fortunato, P. Barquinha, A. Pimentel, A. Gonçalves, A. Marques, L. Pereira and R. Martins, “Recent advances in ZnO transparent thin film transistors,” Thin Solid Films, vol. 487, p. 205, 2005.
A. L. Fahrenbruch, R. H. Bube, Fundamentals of Solar Cells (Academic, New York, 1993).
L. E. Greene, M. Law, J. Goldberger, F. Kim, J. C. Johnson, Y. Zhang, R. J. Saykally and P. Yang, “Low-temperature wafer-scale production of ZnO nanowire arrays,” Angew. Chem. Int. Ed., vol. 42, p. 3031, 2003.
A. B. Djurišić, Y. H. Leung, K. H. Tam, L. Ding, W. K. Ge, H. Y. Chen and S. Gwo, “Green, yellow, and orange defect emission from ZnO nanostructures: Influence of excitation wavelength,” Appl. Phys. Lett., vol. 88, p. 103107, 2006.
A. B. Djurišić and Y. H. Leung, “Optical properties of ZnO nanostructures,” Small, vol. 2, p. 944, 2006.
R. L. Puurunen, “Random deposition as a growth mode in atomic layer deposition,” Chem. Vap. Deposition, vol. 10, p.159, 2004.
S. M. Smith and H. B. Schlegel, “Molecular orbital studies of zinc oxide chemical vapor deposition:  Gas-phase hydrolysis of diethyl zinc, elimination reactions, and formation of dimers and tetramers,” Chem. Mater., vol. 15, p. 162, 2003.
A. C. Dillon, A. W. Ott, J. D. Way and S. M. George, “Surface chemistry of Al2O3 deposition using Al(CH3)3 and H2O in a binary reaction sequence,” Surface Science, vol. 322, p. 230, 1995.
M. Putkonen, J. Niinistö, K. Kukli, T. Sajavaara, M. Karppinen, H. Yamauchi, L. Niinistö, “ZrO2 Thin Films Grown on Silicon Substrates by Atomic Layer Deposition with Cp2Zr(CH3)2 and Water as Precursors,” Chem. Vap. Deposition, vol. 9, p. 207, 2003.

 
Chapter 5

G. I. Meijer, “Who wins the nonvolatile memory race?” Science, vol. 319, p. 1625, 2008.
K. Shiguya, R. Dittmann, S. B. Mi and R. Waser, “Impact of defect distribution on resistive switching characteristics of Sr2TiO4 thin films,” Adv. Mater., vol. 22, p. 411, 2010.
A Sawa, “Resistive switching in transition metal oxides,” Mater. Today, vol. 11, p. 28, 2008.
S. L. Li, J. Li, Y. Zhang, D. N. Zhengand and K. Tsukagoshi, “Unipolar resistive switching in high-resistivity Pr0.7Ca0.3MnO3 junctions,” Appl. Phys. A: Mater. Sci. Process, vol. 103, p. 21, 2011.
W. Shen, R. Dittmann and R. Waser, “Reversible alternation between bipolar and unipolar resistive switching in polycrystalline barium strontium titanate thin films,” J. Appl. Phys., vol. 107, p.094506, 2010.
J. A. Rodriguez, J. C. Hanson, A. I. Frenkel, J. Y. Kim and M. Pérez, “Experimental and theoretical studies on the reaction of H2 with NiO:  Role of O vacancies and mechanism for oxide reduction,” J. Am. Chem. Soc., vol. 124, p. 346, 2001.
S. Wang, M. Awano and K. Maeda, “Synthesis and characterization of dense NiO-(CGO) cathode interlayer for electrocatalytic reduction of NO,” J. Electrochem. Soc., vol. 150, p. D209, 2003.
D. H. Kwon, K. M. Kim, J. H. Jang, J. M. Jeon, M. H. Lee, G. H. Kim, X. S. Li, G. S. Park, B. Lee, S. Han, M. Kim and C. S. Hwang, “Atomic structure of conducting nanofilaments in TiO2 resistive switching memory,” Nature Nanotechnol. vol. 5, p. 148, 2010.
G. H. Kim, J. H. Lee, J. Y. Seok, S. J. Song, J. H. Yoon, K. J. Yoon, M. H. Lee, K. M. Kim, H. D. Lee, S. W. Ryu, T. J. Park and C. S. Hwang, “Improved endurance of resistive switching TiO2 thin film by hourglass shaped Magnéli filaments,” Appl. Phys. Lett., vol. 92, p. 262901, 2011.
W. Y. Chang, Y. C. Lai, T. B. Wu, S. F. Wang, F. Chen and M. J. Tsai, “Unipolar resistive switching characteristics of ZnO thin films for nonvolatile memory applications,” Appl. Phys. Lett., vol. 92, p.022110, 2008.
D. M. Bagnall, Y. F. Chen, Z. Zhu, T. Yao, M. Y. Shen and T. Goto, “High temperature excitonic stimulated emission from ZnO epitaxial layers,” Appl. Phys. Lett., vol. 73, p. 1083, 1998.
S. Lee, H. Kim, D. J. Yun, S. W. Rhee and K. Yong, “Resistive switching characteristics of ZnO thin film grown on stainless steel for flexible nonvolatile memory devices,” Appl. Phys. Lett., vol. 95, p. 262113, 2009.
N. Xu, L. Liu, X. Sun, X. Liu, D. Han, Y. Wang, R. Han, J. Kang and B. Yu, “Characteristics and mechanism of conduction/set process in TiN/ZnO/Pt resistance switching random-access memories,” Appl. Phys. Lett., vol. 92, p. 232112, 2008.
I. Salaoru, T. Prodromakis, A. Khiat and C. Toumazou, “Resistive switching of oxygen enhanced TiO2 thin-film devices,” Appl. Phys. Lett., vol. 102, p. 013506, 2013.
C. Chandrinou, N. Boukos, C. Stogios and Travlos, “PL study of oxygen defect formation in ZnO nanorods,” Microelectron. J., vol. 40, p. 296, 2009.
F. Oba, S. R. Nishitani, S. Isotani, H. Adachi and I. Tanaka, “Energetics of native defects in ZnO,” J. Appl. Phys., vol. 90, p. 824, 2001.
A. F. Kohan, G. Ceder, D. Morgan and Chris G. Van de Walle, “First-principles study of native point defects in ZnO,” Phys. Rev. B, vol. 61, p. 15019, 2000.
C. Y. Lin, C. Y. Wu, C. Y. Wu, T. Y. Tseng and C. M. Hu, “Modified resistive switching behavior of ZrO2 memory films based on the interface layer formed by using Ti top electrode,” J. Appl. Phys., vol. 102, p. 094101, 2007.
C. H. Huang, J. S. Huang, S. M. Lin, W. Y. Chang, J. H. He and Y. L. Chueh, “ZnO1–x nanorod arrays/ZnO thin film bilayer structure: From homojunction diode and high-performance memristor to complementary 1D1R application,” ACS Nano, vol. 6, p. 8407, 2012.
M. Lanza, G. Bersuker, M. Porti, E. Miranda, M. Nafría and X. Aymerich, “Resistive switching in hafnium dioxide layers: Local phenomenon at grain boundaries,” Appl. Phys. Lett., vol. 101, p. 193502, 2012.
A. Schulman, M. J. Rozenberg and C. Acha, “Anomalous time relaxation of the nonvolatile resistive state in bipolar resistive-switching oxide-based memories,” Phys. Rev. B, vol. 86, p. 104426, 2012.
J. W. Seo, J. W. Park, K. S. Lim, J. H. Yang and S. J. Kang, “Transparent resistive random access memory and its characteristics for nonvolatile resistive switching,” Appl. Phys. Lett., vol. 93, p. 223505, 2008.
B. D. Cullity and S. R. Stock, “Elements of X-ray diffraction,” third edition, p167.
L. J. Meng and Santos dos M. P., “Characterization of ZnO films prepared by dc reactive magnetron sputtering at different oxygen partial pressures,” Vacuum, vol. 46, p. 1001, 1995.
S. J. Kang, H. H. Shin and Y. S. Yoon, “Optical and hall properties of ZnO thin films fabricated by using the pulsed laser deposition method at various oxygen pressures and substrate temperatures,” J. Korean Phys. Soc., vol. 51, p. 183, 2007.
J. S. Kang, H. S. Kang, S. S. Pang, E. S. Shim and S. Y. Lee, “Investigation on the origin of green luminescence from laser-ablated ZnO thin film,” Thin Solid Films, vol. 443, p. 5, 2003.
R. Hong, H. Qi, J. Huang, H. He, Z. Fan and J. Shao, “Influence of oxygen partial pressure on the structure and photoluminescence of direct current reactive magnetron sputtering ZnO thin films,” Thin Solid Films, vol. 473, p. 58, 2005.
K. Ellmer, “Magnetron sputtering of transparent conductive zinc oxide: relation between the sputtering parameters and the electronic properties,” J. Phys., D, Appl. Phys., vol. 33, p. R17, 2000.
M. D. McCluskey and S. J. Jokela, “Defects in ZnO,” J. Appl. Phys., vol. 106, p. 071101, 2009.
F. Oba, M. Choi, A. Togo and I. Tanaka, “Point defects in ZnO: An approach from first principles,” Sci. Technol. Adv. Mater., vol. 12, p. 034302, 2011.
N. Xu, L. F. Liu, X. Sun, C. Chen, Y. Wang, D. D. Han, X. Y. Liu, R. Q. Han, J. F. Kang and B. Yu, “Bipolar switching behavior in TiN/ZnO/Pt resistive nonvolatile memory with fast switching and long retention,” Semicond. Sci. Technol., vol. 23, p. 075019, 2008.
H. C. Ong and G. T. Du, “The evolution of defect emissions in oxygen-deficient and -surplus ZnO thin films: the implication of different growth modes,” J. Cryst. Growth, vol. 265, p. 471, 2004.
B. I. Kim, S. C. Kim, B. C. Shin, T. S. Kim, M. Y. Jung and Y. S. Yu, “High-pressure oxygen treatment of ZnO thin films,” Physica B., vol. 376-377, p. 752, 2006.
S. S. Kurbanov, G. N. Panin, T. W. Kim and T. W. Kang, “Strong violet luminescence from ZnO nanocrystals grown by the low-temperature chemical solution deposition,” J. Lumin., vol. 129, p.1099, 2009.
C. Chandrinou, N. Boukos, C. Stogios and A. Travlos, “PL study of oxygen defect formation in ZnO nanorods,” Microelectron. J., vol. 40, p. 296, 2009.
E. G. Bylander, “Surface effects on the low‐energy cathodoluminescence of zinc oxide,” J. Appl. Phys., vol. 49, p. 1188, 1978.
M. Liu, A.H. Kitai and P. Mascher, “Point defects and luminescence centres in zinc oxide and zinc oxide doped with manganese,” J. Lumin., vol. 54, p.35, 1992.
K. J. Laidler, “The development of the Arrhenius equation,” J. Chem. Educ., vol. 61, p. 292, 1984.
H. J. Egelhaaf and D. Oelkrug, “Luminescence and nonradiative deactivation of excited states involving oxygen defect centers in polycrystalline ZnO,” J. Cryst. Growth, vol. 161, p. 190, 1996.
T. Gu, “Role of oxygen vacancies in TiO2-based resistive switches,” J. Appl. Phys., vol. 113, p. 033707, 2013.

Chapter 6

E. Linn, R. Rosezin, C. Kügeler and R. Waser, “Complementary resistive switches for passive nanocrossbar memories,” Nature Mater., vol. 9, p. 403, 2010.
W. Lee, J. Park, S. Kim, J. Woo, J. Shin, G. Choi, S. Park, D. Lee, E. Cha, B. H. Lee and H. Hwang, “High current density and nonlinearity combination of selection device based on TaOx/TiO2/TaOx structure for one selectorone resistor arrays,” ACS nano, vol. 6, p. 8166, 2012.
J. Woo, D. Lee, G. Choi, E. Cha, S. Kim, W. Lee, S. Park and H. Hwang, “Selector-less RRAM with non-linearity of device for cross-point array applications,” Microelectron. Eng., vol. 109, p. 360, 2013.

Chapter 8

D. Perego, S. Franz, M. Bestetti, L. Cattaneo, S. Brivio, G. Tallarida and S. Spiga, “Engineered fabrication of ordered arrays of Au–NiO–Au nanowires,” Nanotechnology, vol. 24, p. 045302, 2013.
J. S. Tresback, A. L. Vasiliev, N. P. Padture, S. Y. Park and P. R. Berger, “Characterization and electrical properties of individual Au–NiO–Au heterojunction nanowires,” IEEE Trans. Nanotechnol., vol. 6, p. 676, 2007.
S. H. Lyu and J. S. Lee, “Highly scalable resistive switching memory cells using pore-size-controlled nanoporous alumina templates,” J. Mater. Chem., vol. 22, p. 1852, 2012.