傳統浮動閘極記憶體的氧化層在操作過程中如果損壞，將使記憶體失去功能，因此氧化層的厚度會有個物理上的極限存在，其中電阻式記憶體因構造簡單且耐用度高，可望解決目前記憶體所面臨的問題，被視為是下一代非揮發性記憶體的技術。目前電阻式記憶體技術若要走向商業化，其機制以及穩定性是必須解決的問題，而眾多研究單位認為奈米粒子的摻雜能改善電阻轉換時的穩定度，並認為奈米粒子的摻雜與電阻轉換機制相關，因此許多研究利用聚合物奈米複合材料來製備電阻式記憶體。DNA除了具備製程簡單、可撓性、環境友善等優點，其特殊結構與特性被眾多研究單位證實能穩定合成金屬奈米粒子，在此之前已有許多研究利用DNA奈米複合物應用在光電元件上。

在此論文中，我們採用光還原法來製備銀奈米粒子於DNA生物聚合物中，藉由吸收光譜及動態光散射粒徑分析儀的量測，結果指出利用光還原系統下形成金屬奈米粒子時，以DNA生物聚合物當作主體會比其他常見的高分子聚合物來的穩定。接著元件為簡單的三明治結構，由旋轉塗佈的DNA奈米複合物薄膜搭配上下電極所組成(金屬/DNA奈米複合物/ITO)，藉由電性的量測，我們發現隨照光時間增加時會出現不同功能性元件，包含一次寫入唯讀記憶體(WORM-Write-Once Read Many Times)、可抹除式記憶體元件(Rewritable memory)及類似導體(Conductor)的特性。

最後我們對電阻轉換的機制進行驗證，藉由改變不同元件的面積、溫度以及電極材料進行電性量測與分析，我們認為元件中金屬導通路徑的形成與破壞是元件出現的電阻轉換現象的機制，希望藉由這樣的機制推論讓DNA奈米複合物在光電科技的應用中能開啟新的方向。

In the near future, flash memory will face a great deal of challenges because of miniaturization and physical
limit. Resistive random access memory (RRAM) has a simple structure and high endurance performance, which is one of the promising candidates for next generation memory application. Nowadays, some serious problems still need to be resolved toward the commercialization of RRAM, including stability and the mechanism. For memory devices made of polymer composites, some studies have shown that the stability can be improved by introducing nanoparticles, which also play crucial roles for switching mechanisms. As one type of biopolymers, deoxyribonucleic acid(DNA) has serious advantages, including ease of preparation, flexible and environmentally friendly. Moreover, recent studies have revealed that DNA biopolymer-nanoparticles composite may also find extensive applications in electronic and optoelectronic devices.

In this study, we adopt a photochemical method to synthesize silver nanoparticles in DNA biopolymer. The characterizations of UV-VIS spectra and dynamic light scattering suggest that such photoinduced synthesis of silver nanoparticles in DNA biopolymer is more effective than that in other hosts. Then the device is fabricated based on a simple sandwich structure with a spin-coated DNA biopolymer layer sandwiched by two electrodes(Metal/DNA biopolymer nanocomposites/ITO). The electrical properties of the device are adjusted with increasing irradiation time, which shows write-once read many times(WORM), rewritable memory and conductor behavior.

We further verify the switching mechanism by examining the electrical properties under different device areas,
temperatures and electrodes. Based on the characterization results, we propose possible resistance switching mechanisms based on the formation and rupture of conductive paths. These verifications can open new avenues for various optoelectronic applications based on DNA biopolymer nanocomposites.

目 錄

致謝 I 摘要 III Abstract IV 目錄 V
第一章 緒論 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 前言 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2 電陣式記憶體的簡介 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2.1 電陣式記憶體的發展 . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2.2 電陣式記憶體的轉換機制 . . . . . . . . . . . . . . . . . . . . . . 4

1.2.3 金屬與介電材料電流傳導機制 . . . . . . . . . . . . . . . . . . . 8
1.3 DNA-金屬奈米拉子複合物介紹 . . . . . . . . . . . . . . . . . . . . . . 12
1.3.1 DNA簡介與其應用 . . . . . . . . . . . . . . . . . . . . . . . . . . 12

1.3.2 DNA-CTMA簡介與其應用 . . . . . . . . . . . . . . . . . . . . . 13

1.3.3 金屬奈米拉子簡介 . . . . . . . . . . . . . . . . . . . . . . . . . . 14

1.3.4 金屬奈米拉子製備方法 . . . . . . . . . . . . . . . . . . . . . . . 15

1.3.5 DNA-金屬奈米拉子複合物 . . . . . . . . . . . . . . . . . . . . . 16
1.4 研究動機 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
第二章 實驗方法 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.1 材料製備 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.1.1 DNA高分子聚合物製備 . . . . . . . . . . . . . . . . . . . . . . . 19

2.1.2 DNA高分子奈米拉子-複合物製備 . . . . . . . . . . . . . . . . . 20


2.2.1 基本元件設計與製備. . . . . . . . . . . . . . . . . . . . . . .20
2.2.2 機制驗證-元件設計與製備 . . . . . . . . . . . . . . . . . . . . . . .22
2.2.3 量測儀器 . . . . . . . . . . . . . . . . . . . . . . .23
第三章 材料特性與基本元件的量測與分析 . . . . . . . . . . . . . . . . . . . . . . . 26

3.1 材料特性分析 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
3.1.1 光還原系統-不同主體可見光頻段吸收光譜 . . . . . . . . . . . . 26
3.1.2 光還原系統-動慈光散射拉徑分析儀光譜 . . . . . . . . . . . . . 31
3.2 元件特性分析 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.2.1 電流電壓特性 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

3.2.2 特性分析 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

3.2.3 持久度分析(Retention time) . . . . . . . . . . . . . . . . . . . . . 42

3.2.4 不同照光時間電流與電壓的特性 . . . . . . . . . . . . . . . . . . 43
3.3 結果與討論 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
3.3.1 照光時間對於寫入電壓的影響 . . . . . . . . . . . . . . . . . . . 46

3.3.2 高導慈電陣的初步探討 . . . . . . . . . . . . . . . . . . . . . . . 47

3.3.3 不同照光時間元件的操作特性 . . . . . . . . . . . . . . . . . . . 48

第四章 元件機制驗證與討論 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

4.1 調變電極種類之電性量測 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
4.2 調變主動層面積之電性量測. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
4.3 溫度調變其電性關係 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55

4.3.1 低導(OFF state)時電性與溫度關係. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .55
4.3.2 高導(ON state)時電性與溫度關係 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
4.3.3 溫度係數 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
第五章 結果與未來展望 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60


參考文獻 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

[1] http://www.techbang.com/posts/18381-from-the-channel-to-address-computer-main- memory-structures-to-understand.
[2] D. Kahng and S. M. Sze, “A floating gate and its application to memory devices,” Bell System Technical Journal 46, 1288–1295 (1967).
[3] R. Waser, R. Dittmann, G. Staikov, and K. Szot, “Redox-based resistive switching memories–nanoionic mechanisms, prospects, and challenges,” Advanced Materials21, 2632–2663 (2009).
[4] F. Pan, S. Gao, C. Chen, C. Song, and F. Zeng, “Recent progress in resistive random access memories: Materials, switching mechanisms, and performance,” Materials Science and Engineering: R: Reports 83, 1 – 59 (2014).
[5] S. Gao, C. Song, C. Chen, F. Zeng, and F. Pan, “Formation process of conducting filament in planar organic resistive memory,” Applied Physics Letters 102, 141606 (2013).
[6] Z. B. Yan and J. M. Liu, “Coexistence of high performance resistance and capac- itance memory based on multilayered metal-oxide structures,” Scientific reports 3, 2482 (2013).
[7] Y. Yang, F. Pan, F. Zeng, and M. Liu, “Switching mechanism transition induced by annealing treatment in nonvolatile Cu/Zno/Cu/Zno/Pt resistive memory: from carrier trapping/detrapping to electrochemical metallization,” Journal of Applied Physics 106, 123705 (2009).
[8] L. H. Xie, Q. D. Ling, X. Y. Hou, and W. Huang, “An effective friedel-crafts postfunc- tionalization of poly (n-vinylcarbazole) to tune carrier transportation of supramolec- ular organic semiconductors based on π-stacked polymers for nonvolatile flash memory cell,” Journal of the American Chemical Society 130, 2120–2121 (2008).
[9]S. L. Lim, Q. Ling, E. Y. H. Teo, C. X. Zhu, D. S. H. Chan, E. T. Kang, and K. G.
Neoh, “Conformation-induced electrical bistability in non-conjugated polymers with pendant carbazole moieties,” Chemistry of Materials 19, 5148–5157 (2007).
[10] N. Kobayashi and K. Nakamura, “DNA electronics and photonics,” in “Electronic Processes in Organic Electronics,” (Springer, 2015), pp. 253–281.
[11] T. B. Singh, N. S. Sariciftci, and J. G. Grote, “Bio-organic optoelectronic devices using DNA,” in “Organic Electronics,” (Springer, 2009), pp. 73–112.
[12] K. L. Kelly, E. Coronado, L. L. Zhao, and G. C. Schatz, “The optical properties of metal nanoparticles: The influence of size, shape, and dielectric environment,” The Journal of Physical Chemistry B 107, 668–677 (2003).
[13] K. G. Stamplecoskie and J. C. Scaiano, “Light emitting diode irradiation can con- trol the morphology and optical properties of silver nanoparticles,” Journal of the American Chemical Society 132, 1825–1827 (2010).
[14] S. Gao, C. Song, C. Chen, F. Zeng, and F. Pan, “Dynamic processes of resistive switching in metallic filament-based organic memory devices,” The Journal of Phys- ical Chemistry C 116, 17955–17959 (2012).
[15] W. Guan, S. Long, Q. Liu, M. Liu, and W. Wang, “Nonpolar nonvolatile resistive switching in Cu doped,” IEEE Electron Device Letters 29, 434–437 (2008).
[16] J. Yang, F. Zeng, Z. S. Wang, C. Chen, G. Y. Wang, Y. S. Lin, and F. Pan, “Mod- ulating resistive switching by diluted additive of poly(vinylpyrrolidone) in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate),” Journal of Applied Physics 110,114518 (2011).
[17] Z. Wang, F. Zeng, J. Yang, C. Chen, and F. Pan, “Resistive switch- ing induced by metallic filaments formation through poly(3,4-ethylene- dioxythiophene):poly(styrenesulfonate),” ACS Applied Materials & Interfaces 4, 447–453 (2012).
[18] B. Sun, L. Wei, H. Li, X. Jia, J. Wu, and P. Chen, “The DNA strand assisted conductive filament mechanism for improved resistive switching memory,” Journal of Materials Chemistry C 3, 12149–12155 (2015).
[19] Y. Wang, X. Yan, and R. Dong, “Organic memristive devices based on silver nanoparticles and DNA,” Organic Electronics 15, 3476 – 3481 (2014).
[20] C. Ho, C. L. Hsu, C. C. Chen, J. T. Liu, C. S. Wu, C. C. Huang, C. Hu, and F. L.Yang, “9nm half-pitch functional resistive memory cell with &# 60; 1µA program- ming current using thermally oxidized sub-stoichiometric WOx film,” in “Electron Devices Meeting (IEDM),” (2010), pp. 19–1.
[21] A. C. Torrezan, J. P. Strachan, G. Medeiros-Ribeiro, and R. S. Williams, “Sub- nanosecond switching of a tantalum oxide memristor,” Nanotechnology 22, 485203 (2011).
[22] C. H. Cheng, C. Y. Tsai, A. Chin, and F. Yeh, “High performance ultra-low energy rram with good retention and endurance,” in “Electron Devices Meeting (IEDM), 2010 IEEE International,” (2010), pp. 19–4.
[23] M. J. Lee, C. B. Lee, D. Lee, S. R. Lee, M. Chang, J. H. Hur, Y.-B. Kim, C. J.
Kim, D. H. Seo, S. Seo et al., “A fast, high-endurance and scalable non-volatile memory device made from asymmetric Ta2O5−x/TaO2−x bilayer structures,” Nature materials 10, 625–630 (2011).
[24] Y. S. Chen, P. S. Chen, H. Y. Lee, T. Y. Wu, K. H. Tsai, F. Chen, and M. J. Tsai, “Enhanced endurance reliability and low current operation for AlOx/HfOx based unipolar RRAM with Ni electrode,” Solid-State Electronics 94, 1 – 5 (2014).
[25] K. Kinoshtia, T. Okutani, H. Tanaka, T. Hinoki, K. Yazawa, K. Ohmi, and
S. Kishida, “Opposite bias polarity dependence of resistive switching in n-type Ga- doped-ZnO and p-type NiO thin films,” Applied Physics Letters 96, 143505 (2010).
[26] Q. D. Ling, S. L. Lim, Y. Song, C. X. Zhu, D. S. H. Chan, E. T. Kang, and K. G. Neoh, “Nonvolatile polymer memory device based on bistable electrical switching in
a thin film of poly (n-vinylcarbazole) with covalently bonded C60,” Langmuir 23,
312–319 (2007).
[27] J. D. Watson and F. H. C. Crick, “Molecular structure of nucleic acids: A structure for deoxyribose nucleic acid,” Nature 171, 737 – 738 (1953).
[28] J. Zhang, Y. Liu, Y. Ke, and H. Yan, “Periodic square-like gold nanoparticle arrays templated by self-assembled 2D DNA nanogrids on a surface,” Nano Letters 6, 248–251 (2006).
[29] K. Aoi, A. Takasu, and M. Okada, “DNA-based polymer hybrids part 1. compatibil- ity and physical properties of poly(vinyl alcohol)/DNA sodium salt blend,” Polymer 41, 2847 – 2853 (2000).
[30] C. Alemn, B. T. Dias, D. Zanuy, F. Estrany, E. Armelin, and L. J. del Valle, “A comprehensive study of the interactions between DNA and poly(3,4-ethylenedioxythiophene),” Polymer 50, 1965 – 1974(2009).
[31] Z. Zhou, Y. Du, and S. Dong, “Double-strand DNA-templated formation of copper nanoparticles as fluorescent probe for label-free aptamer sensor,” Analytical Chem- istry 83, 5122–5127 (2011).
[32] I. Diez and R. H. A. Ras, “Fluorescent silver nanoclusters,” Nanoscale 3, 1963–1970 (2011).
[33] G. Wei, H. Zhou, Z. Liu, Y. Song, L. Wang, L. Sun, and Z. Li, “One-step synthesis of silver nanoparticles, nanorods, and nanowires on the surface of DNA network,” The Journal of Physical Chemistry B 109, 8738–8743 (2005).
[34] N. J. Halas, “Plasmonics: An emerging field fostered by Nano Letters,” Nano Letters
10, 3816–3822 (2010).
[35] Y. C. Hung, P. Mueller, Y. S. Wang, and L. Fruk, “Phototriggered growth of crys- talline Au structures in the presence of a DNA-surfactant complex,” Nanoscale 4, 5585–5587 (2012).
[36] A. J. Steckl, “DNA-a new material for photonics,” Nature Photonics 1, 3–5 (2007).
[37] Y. Kawabe, L. Wang, S. Horinouchi, and N. Ogata, “Amplified spontaneous emission from fluorescent-dye-doped DNA–surfactant complex films,” Advanced Materials 12, 1281–1283 (2000).
[38] L. Wang, J. Yoshida, N. Ogata, S. Sasaki, and T. Kajiyama, “Self-assembled supramolecular films derived from marine deoxyribonucleic acid (DNA)-cationic sur-factant complexes: Large-scale preparation and optical and thermal properties,” Chemistry of Materials 13, 1273–1281 (2001).
[39] J. A. Hagen, W. Li, A. J. Steckl, and J. G. Grote, “Enhanced emission efficiency
in organic light-emitting diodes using deoxyribonucleic acid complex as an electron blocking layer,” Applied Physics Letters 88, 171109 (2006).
[40] V. Kolachure and M. H. C. Jin, “Fabrication of P3HT/PCBM bulk heterojunc- tion solar cells with DNA complex layer,” in “Photovoltaic Specialists Conference,,” (2008), pp. 1–5.
[41] B. Singh, N. S. Sariciftci, J. G. Grote, and F. K. Hopkins, “Bio-organic- semiconductor-field-effect-transistor based on deoxyribonucleic acid gate dielectric,” Journal of Applied Physics 100, 024514 (2006).
[42] Y.-C. Hung, D. M. Bauer, I. Ahmed, and L. Fruk, “DNA from natural sources in design of functional devices,” Methods 67, 105 – 115 (2014).
[43] S. Basu, S. Jana, S. Pande, and T. Pal, “Interaction of DNA bases with silver nanoparticles: Assembly quantified through SPRS and SERS,” Journal of Colloid
and Interface Science 321, 288 – 293 (2008).
[44] J. T. Petty, J. Zheng, N. V. Hud, and R. M. Dickson, “DNA-templated Ag nanoclus- ter formation,” Journal of the American Chemical Society 126, 5207–5212 (2004).
[45] E. Braun, Y. Eichen, U. Sivan, and G. Ben Yoseph, “DNA-templated assembly and electrode attachment of a conducting silver wire,” Nature 391, 775–778 (1998).
[46] C. F. Monson and A. T. Woolley, “DNA-templated construction of copper nanowires,” Nano Letters 3, 359–363 (2003).
[47] A. Kumar, M. Pattarkine, M. Bhadbhade, A. B. Mandale, K. N. Ganesh, S. S. Datar, C. V. Dharmadhikari, M. Sastry et al., “Linear superclusters of colloidal gold particles by electrostatic assembly on DNA templates,” Advanced Materials
13, 341–344 (2001).
[48] Y. C. Hung, T. Y. Lin, W. T. Hsu, Y. W. Chiu, Y. S. Wang, and L. Fruk, “Functional DNA biopolymers and nanocomposite for optoelectronic applications,” Optical Ma- terials 34, 1208 – 1213 (2012).
[49] Y. C. Hung, W. T. Hsu, T. Y. Lin, and L. Fruk, “Photoinduced write-once read- many-times memory device based on DNA biopolymer nanocomposite,” Applied Physics Letters 99, 253301 (2011).
[50] E. M. Heckman, J. A. Hagen, P. P. Yaney, J. G. Grote, and F. K. Hopkins, “Pro- cessing techniques for deoxyribonucleic acid: Biopolymer for photonics applications,” Applied Physics Letters 87, 211115 (2005).
[51] G. A. Mart´ınez-Castan˜o´n, N. Nin˜o-Mart´ınez, F. Mart´ınez-Gutierrez, J. R. Mart´ınez- Mendoza, and F. Ruiz, “Synthesis and antibacterial activity of silver nanoparticles with different sizes,” Journal of Nanoparticle Research 10, 1343–1348 (2008).
[52] C. Y. Hung, W. T. Tu, Y. T. Lin, L. Fruk, and Y.-C. Hung, “Optically con- trolled multiple switching operations of DNA biopolymer devices,” Journal of Ap- plied Physics 118, 235503 (2015).
[53] S. Pal, Y. K. Tak, and J. M. Song, “Does the antibacterial activity of silver nanopar- ticles depend on the shape of the nanoparticle? A study of the gram-negative bac- terium escherichia coli,” Applied and Environmental Microbiology 73, 1712–1720 (2007).
[54] Z. Chiguvare, J. Parisi, and V. Dyakonov, “Current limiting mechanisms in indium- tin-oxide/poly3-hexylthiophene/aluminum thin film devices,” Journal of Applied
Physics 94, 2440–2448 (2003).
[55] T. L. Chiu, W. F. Xu, C. F. Lin, J. H. Lee, C. C. Chao, and M. K. Leung, “Opti- cal and electrical characteristics of Ag-doped perylene diimide derivative,” Applied Physics Letters 94, 13307 (2009).
[56] Y. Sun, L. Li, D. Wen, X. Bai, and G. Li, “Bistable electrical switching and nonvolatile memory effect in carbon nanotube–poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) composite films,” Physical Chemistry Chemical Physics 17, 17150–17158 (2015).
[57] D. I. Son, D. H. Park, W. K. Choi, S. H. Cho, W. T. Kim, and T. W. Kim, “Carrier transport in flexible organic bistable devices of ZnO nanoparticles embedded in an insulating poly(methyl methacrylate) polymer layer,” Nanotechnology 20, 195203 (2009).
[58] C. Chen, S. Gao, F. Zeng, G. S. Tang, S. Z. Li, C. Song, H. D. Fu, and F. Pan, “Migration of interfacial oxygen ions modulated resistive switching in oxide-based memory devices,” Journal of Applied Physics 114, 014502 (2013).
[59] E. M. Heckman, J. G. Grote, P. P. Yaney, and F. K. Hopkins, “DNA-based nonlinear photonic materials,” in “Optical Science and Technology, the SPIE 49th Annual Meeting,” (2004), pp. 47–51.
[60] A. Bid, A. Bora, and A. K. Raychaudhuri, “Temperature dependence of the resis- tance of metallic nanowires of diameter “ 15 nm: Applicability of bloch-gru¨neisen theorem,” Physical Review B 74, 035426 (2006).