隨著3C產業的發展，可攜式電子產品在日常生活中開始扮演重要的角色，並接著帶動了記憶體的演進。鐵電記憶體是相當被看好的一種非揮發性記憶體，以MFIS場效電晶體作為主要結構的鐵電記憶體除了具有非揮發性，還具有高耐久度、低能耗、以及操作快速的特性，因而獲得高度的重視。目前為止己經有許多不同的研究團隊分別使用了不同的鐵電材料及絕緣材料來建構MFIS結構，並針對其特性做研究及分析。包括PZT、SBT、BLT、YMO…等不同的鐵電材料以及HfO2、Y2O3…等不同的絕緣材料己被大量研究。在本實驗中，我們使用了化學液相沉積法(chemical solution deposition)，在p-type的矽基板上鍍製了單相的氧化鋯(ZrO2)及鐵酸鉍(BiFeO3)薄膜。在我們的實驗中，使用了不同的熱處理條件，以及不同的摻雜原子來改變MFIS結構的特性，並藉此得到一個最佳的處理條件。在我們的實驗中，我們發現在As-Deposited的氧化鋯上鍍製鐵酸鉍，並且以氧氣氛在攝氏五百度之下進行熱處理，所完成的MFIS結構可在±6V的電壓下獲得約0.78V的記憶窗口，雖然還不算太大，但以鐵酸鉍的高極性及高矯頑場，相信這個材料仍有相當大的發展空間。

摘要------------------------------------------------------I
目錄----------------------------------------------------III
表目錄--------------------------------------------------VII
圖目錄--------------------------------------------------VII

第一章　前言----------------------------------------------1
1-1.記憶體簡介--------------------------------------------1
1-2.鐵電材料BiFeO3及絕緣材料ZrO2 ------------------------2
第二章 文獻回顧------------------------------------------4
2-1.FeRAM-------------------------------------------------4
2-1-1.破壞性讀取與非破壞性讀取------------------------4
2-1-2.FeRAM的類型 ------------------------------------6
2-2.鐵電材料----------------------------------------------8
2-3.介電性質---------------------------------------------11
2-3-1.極化機制（Polarization Mechanisms）------------11
2-3-2.介電常數和散逸因子-----------------------------12
2-3-3.介電崩潰機制---------------------------------------13
2-3-4.漏電流機制-----------------------------------------13
2-4.BiFeO3 特性介紹--------------------------------------15
2-4-1.晶格結構-------------------------------------------15
2-4-2.優點-----------------------------------------------16
2-4-3.缺點-----------------------------------------------17
2-5.絕緣層於MFIS結構中之應用-----------------------------18
第三章 實驗流程-----------------------------------------29
3-1.溶液之配製-------------------------------------------29
3-1-1.ZrO2 溶液------------------------------------------29
3-1-2.BiFeO3 溶液----------------------------------------29
3-2.基板之前處理-----------------------------------------30
3-3.Pt-ZrO2-Si之MIS結構----------------------------------31
3-3-1.薄膜旋鍍-------------------------------------------31
3-3-2.薄膜熱處理-----------------------------------------31
3-3-3.黃光製程鍍製白金上電極-----------------------------32
3-3-4.RTA電極退火 ---------------------------------------32
3-4.Pt-BiFeO3-ZrO2-Pt之MFIS結構 -------------------------32
3-4-1.薄膜旋鍍-------------------------------------------32
3-4-2.薄膜熱處理-----------------------------------------33
3-4-3.黃光製程鍍製白金上電極-----------------------------33
3-4-4.RTA電極退火 ---------------------------------------33
3-5.薄膜之物性量測---------------------------------------33
3-5-1.XRD結晶繞射分析 -----------------------------------33
3-5-2.SEM------------------------------------------------33
3-6.薄膜之電性量測---------------------------------------34
3-6-1.I-V量測 ---------------------------------------34
3-6-2.C-V量測 ---------------------------------------34
第四章 結果討論-----------------------------------------40
4-1. MIS結構Pt/ZrO2/Si ----------------------------------40
4-1-1. XRD pattern-----------------------------------40
4-1-2. SEM figure------------------------------------40
4-1-3. I-V Characteristics---------------------------41
4-1-4. C-V Characteristics---------------------------41
4-2. MFIS結構Pt/BiFeO3/ZrO2(700℃post annealed)/Si-------42
4-2-1. XRD pattern-----------------------------------42
4-2-2. SEM figure------------------------------------43
4-2-3. I-V Characteristics---------------------------43
4-2-4. C-V Characteristic----------------------------43
4-3. MFIS結構Pt/Bi0.95La0.05FeO3/ZrO2/Si
Pt/BiFe0.98Ti0.02O3/ZrO2/Si---------------------45
4-3-1. XRD pattern-----------------------------------46
4-3-2. SEM figure------------------------------------46
4-3-3. I-V Characteristics---------------------------46
4-3-4. C-V Characteristics---------------------------47
4-4. MFIS結構Pt/BiFeO3/ZrO2(Un-annealed)/Si--------------48
4-4-1. XRD Pattern-----------------------------------48
4-4-2. SEM Figure------------------------------------48
4-4-3. I-V Characteristics---------------------------48
4-4-4. C-V Characteristics---------------------------48
4-5. 綜合比較--------------------------------------------49
4-5-1. 結晶狀態--------------------------------------50
4-5-2. 漏電性質--------------------------------------50
4-5-3. C-V特性 --------------------------------------51
第五章 結論---------------------------------------------84
參考文獻-------------------------------------------------87



表目錄
[表2-1]PZT, SBT, BLT三種鐵電材料比較圖-------------------27
[表2-2]絕緣體的漏電傳導機制------------------------------28
圖目錄
[圖2-1]鐵電材料之P-E曲線--------------------------------20
[圖2-2]MFIS FETs結構圖-----------------------------------20
[圖2-3]MFIS結構之記憶機構 -------------------------------21
[圖2-4]MFMIS結構圖 --------------------------------------22
[圖2-5]All Epitaxial Perovskite FET---------------------22
[圖2-6]1T-2C FET及其二元極化方向-------------------------23
[圖2-7]Perovskite結構 -----------------------------------23
[圖2-8]鋯酸鉛鈦之相圖------------------------------------24
[圖2-9]四種極化機制--------------------------------------25
[圖2-10]不同極化機制對頻率大小的關係圖-------------------26
[圖2-11]BFO原子排列結構圖 -------------------------------26
[圖2-12]BiFeO3菱形與正方晶之原子排列示意圖- -------------27
[圖3-1] ZrO2溶液的配置流程-------------------------------35
[圖3-2] BiFeO3溶液的配置流程-----------------------------36
[圖3-3] 矽基板的清洗流程---------------------------------37
[圖3-4]ZrO2薄膜鍍製流程----------------------------------37
[圖3-5]BiFeO3薄膜鍍製流程--------------------------------38
[圖3-6]MFIS structure電性量測示意圖----------------------39
[圖4-1a] ZrO2/Si正常掃描之X光繞射圖---------------------58
[圖4-1b] ZrO2/Si以低掠角掃描之X光繞射圖-----------------58
[圖4-2]ZrO2/Si經過600度十分鐘熱處理之後，
表面的SEM圖形 ------------------------------------59
[圖4-3]ZrO2/Si經過600度二十分鐘熱處理之後，
表面的SEM圖形 ------------------------------------59
[圖4-5]ZrO2在不同退火溫度下的漏電流圖形------------------60
[圖4-4]ZrO2/Si經過攝氏700度十分鐘熱處理，
表面的SEM圖形 ------------------------------------60
[圖4-6]ZrO2在不同熱處理溫度及時間的C-V曲線--------------61
[圖4-7]BiFeO3/ZrO2(Post annealed)/Si之X-ray繞射圖 -------61
[圖4-8]BiFeO3/ZrO2(post annealed)/Si結構，BFO的表面形貌--62
[圖4-9] BiFeO3/ZrO2(post annealed)/Si之橫截面結構---------62
[圖4-10] BiFeO3/ZrO2(post annealed)/Si之I-V曲線----------63
[圖4-11] BiFeO3/ZrO2(post annealed)/Si在±5V內量測之C-V曲線
退火條件為預退火700度，退火550度---------------63
[圖4-12] BiFeO3/ZrO2(post-annealed)/Si在±6V以上量測C-V曲線
退火條件為預退火700度，退火550度---------------64
[圖4-13] BiFeO3/ZrO2(post-annealed)/Si C-V曲線
退火條件為預退火600度，退火550度---------------64
[圖4-14] BiFeO3/ZrO2(post-annealed)/Si C-V曲線
退火條件為預退火700度，退火500度---------------65
[圖4-15] BiFeO3/ZrO2(post annealed)/Si
Flat band voltage對Sweep Voltage的作圖---------65
[圖4-16]BiFeO3/ZrO2(post annealed)/Si
memory window對sweep voltage作圖---------------66
[圖4-17] Bi0.95La0.05FeO3/ZrO2/Si及BiFe0.97Ti0.03O3/ZrO2/Si結構
之X光繞射圖 ------------------------------------66
[圖4-18] Bi0.95La0.05FeO3/ZrO2/Si之表面SEM圖-----------------67
[圖4-19] BiFe0.97Ti0.03O3/ZrO2/Si之表面SEM圖-----------------67
[圖4-20] Bi0.95La0.05FeO3/ZrO2/Si之橫截面結構-----------------68
[圖4-21] BiFe0.97Ti0.03O3/ZrO2/Si之橫截面結構-----------------68
[圖4-22] Pt/Bi0.95La0.05FeO3/ZrO2/Si及Pt/BiFe0.97Ti0.03O3/ZrO2/Si
之I-V曲線圖 ------------------------------------69
[圖4-23] Pt/Bi0.95La0.05FeO3/ZrO2/Si在±6V內量測之C-V曲線----69
[圖4-24] Pt/Bi0.95La0.05FeO3/ZrO2/Si在±7V以上量測之C-V曲線--70
[圖4-25] Pt/Bi0.95La0.05FeO3/ZrO2/Si
Flat band voltage對Sweep Voltage的作圖---------70
[圖4-26] Pt/Bi0.95La0.05FeO3/ZrO2/Si
memory window對sweep voltage作圖----------------71
[圖4-27] Pt/BiFe0.97Ti0.03O3/ZrO2/Si在±4V內量測之C-V曲線----71
[圖4-28] Pt/BiFe0.97Ti0.03O3/ZrO2/Si在±5V以上量測之C-V曲線--72
[圖4-29] Pt/BiFe0.97Ti0.03O3/ZrO2/Si
Flat band voltage對Sweep Voltage的作圖---------72
[圖4-30] Pt/BiFe0.97Ti0.03O3/ZrO2/Si
memory window對sweep voltage作圖---------------73
[圖4-31] BiFeO3/ZrO2(Un-annealed)/Si的X光繞射圖----------73
[圖4-32] Pt/BiFeO3/ZrO2(Un-annealed)/Si的表面SEM圖------74
[圖4-33] Pt/BiFeO3/ZrO2(Un-annealed)/Si的I-V曲線---------74
[圖4-34] Pt/BiFeO3/ZrO2(Un-annealed)/Si，
±2V~±6V的C-V曲線-------------------------------75
[圖4-35] Pt/BiFeO3/ZrO2(Un-annealed)/Si，
±7V~±10V的C-V曲線------------------------------75

[圖4-36] Pt/BiFeO3/ZrO2(Un-annealed)/Si
Flat band voltage對Sweep Voltage作圖------------76
[圖4-37] Pt/BiFeO3/ZrO2(Un-annealed)/Si
memory window對sweep voltage作圖----------------76
[圖4-38]XRD比較圖 ---------------------------------------77
[圖4-39]漏電流比較圖-------------------------------------77
[圖4-40]Memory window比較圖------------------------------78
[圖4-41]BFO的P-E曲線------------------------------------78
[圖4-42] BLFO的P-E曲線----------------------------------79
[圖4-43] BFTO的P-E曲線----------------------------------79
[圖4-44]BFO、BLFO、BFTO的Ec、2Pr關係圖------------------80
[圖4-45]四種carrier分布圖-------------------------------80
[圖4-46]BFO/ZrO2(PA)C-V曲線之變頻量測 -------------------81
[圖4-47]BLFO/ZrO2(PA)C-V曲線之變頻量測 ------------------81
[圖4-48]BFTO/ZrO2(PA)C-V曲線之變頻量測 ------------------82
[圖4-49]BFO/ZrO2(AD)C-V曲線之變頻量測 -------------------82
[圖4-50]ZrO2在高低頻下的C-V特性-------------------------83

[1]- 高明哲 “非揮發性記憶體(NVM)，相變化記憶體(PCM)”
[2]- J. M. Lee, K. T. Kim, and C. I. Kim “Characteristics of Pt/Bi3.25La0.75Ti3O12/ZrO2/Si structures using ZrO2 as buffer layers for ferroelectric-gate field-effect transistors” J. Vac. Sci. Technol. A, 22, No.4 (2004)
[3]- D. Ito, T. Yoshimura, N. Fujimura), T. Ito “Improvement of Y2O3/Si interface for FeRAM application” Applied Surface Science 159–160, 138–142 (2000)
[4]- E.Tokumitsu, T.Isobe, TKijima and H.Ishiwara “Fabrication and characterization of Metal-Ferroelectric-Metal-Insulator-Semiconductor (MFMIS) structures using ferroelectric (Bi,La)4Ti3O12 films” Jpn. J. Appl. Phys.40 5576 (2001)
[5]- A. G. Schrott and J. A. Misewich “Ferroelectric field-effect transistor with a SrRuxTi1-xO3 channel” Appl.Phys.lett.82, 4770 (2003)
[6]- S. Mathews, R. Ramesh, T. Venkatesan, J. Benedetto “Ferroelectric field effect transistor based on epitazxial perovskite heterostructures”SCIENCE, 276,238(1997)
[7]- S. M. Yoon, and H. Ishiwara “Memory operations of 1T2C-type ferroelectric memory cell with excellent data retention characteristics” IEEE Trans.Electron.Dev. 48, 2002(2001)
[8]- H. Ishiwara “Recent progress of FET-Type ferroelectric memories” IEDM, 263 (2003)
[9]- B. Jaffe, W. R. Cooke Jr., and H. Jaffe “Piezoelectric Ceramics”Academic Press,New York,(1971)
[10]- E. G. Lee, Dirk J. Wouters, Geert Willems, and Herman E. Maes,“Influence of Zr/Ti ratios on the deformation in the hysteresis loop of Pb(Zr,Ti)O3 thin film capacitors” Appl. Phys. Lett. 70, 2404 (1997)
[11]- C. S. Liang, J. M. Wu, and M. C. Chang, “Ferroelectric
BaPbO3/PbZr0.53Ti0.47/BaPbO3 heterostructures” Appl. Phys. Lett. 81,3624 (2002)
[12]- S. G. Yoon, A. I. Kingon, and S. H. Kim, “Relaxation and leakage current characteristics of Pb1–xLax(ZryTi1–y)1–x/4O3 thin films with various Ir-based top electrodes” J. Appl. Phys. 88, 6690 (2000)
[13]- S. Y. Chen, C. L. Sun, “Ferroelectric characteristics of oriented Pb(Zr1–xTix)O3 films” J. Appl. Phys. 90, 2970 (2001)
[14]- K. Maki, B. T. Liu, H. Vu, V. Nagarajan, R. Ramesh, Y. Fujimori, T.Nakamura, and H. Takasu, “Controlling crystallization of Pb(Zr,Ti)O3 thin films on IrO2 electrodes at low temperature through interface engineering” Appl. Phys. Lett. 82, 1263 (2003)
[15]- Z. Huang, Q. Zhang, and R. W. Whatmore, “Low temperature
crystallization of lead zirconate titanate thin films by a sol-gel method” J. Appl. Phys. 85 , 7355 (1999)
[16]- J. F. Scott, C. A. Araujo, B.M. Melnick, L.D. McMillan, R. Zuleeg,“Quantitative measurement of space-charge effects in lead zirconate-titanate memories” J. Appl. Phys. 70 , 382 (1991)
[17]- M. Dawber, J. F. Scott, “A model for fatigue in ferroelectric perovskite thin films” Appl. Phys. Lett. 76, 1060 (2000)
[18]- A. J. Moulson and J. M. Herbert, “Electroceramics, materials,properties and applications”, p52-55 and p61-62. (1990)
[19]- 李雅明, “固態電子學”, 全華科技 (1995)
[20]- 吳朗, “電子陶瓷-介電”, 全新資訊圖書 (1994)
[21]- 施修正, “利用濺鍍法以鎳酸鑭為電極製作動態記憶體之鋯鈦酸鋇薄膜的研究” , 清華大學, 博士論文, (1999)
[22]- Y. S. Yang, S. J. Lee, S. H. Kim, B. G. Chae, and M. S. Jang,“Schottky barrier effects in the electronic conduction of sol-gel derived lead zirconate titanate thin film capacitors”, J. Appl. Phys. 84 5005-5011 (1998)
[23]- I. Stolichnov, and A. Tagantsev, “Space-charge influenced-injection model for conduction on Pb(Zr xTi1-x)O3 thin films”, J. Appl. Phys. 84 3216-3225 (1998)
[24]- F. Kubel and H. Schmid: Acta Crystallogr, Sect. B 46, 698 (1990)
[25]- J. Wang, J. B. Neaton, H. Zheng, V. Nagarajan, S. B. Ogale, B. Liu, D. Viehland, V. Vaithyanathan, D. G. Schlom, U. V. Waghmare, N.A. Spaldin, K. M. Rabe, M. Wuttig, and R. Ramesh, “Epitaxial BiFeO3 multiferroic thin film heterostructures” Science 299, 1719 (2003)
[26]- J. F. Li, J. Wang, M. Wuttig, R. Ramesh, N. Wang, B. Ruette, A. P. Pyatakov, A. K. Zvezdin, and D. Viehland, “Dramatically enhanced polarization in (001), (101), and (111) BiFeO3 thin films due to epitiaxial-induced transitions” Appl. Phys. Lett. 84, 5261 (2004).
[27]- K. Y. Yun, D. Ricinschi, T. Kanashima, M. Noda and M. Okuyama, “Giant ferroelectric polarization beyond 150 µC/cm2 in BiFeO3 thin film” Jpn. J. Appl. Phys. 43, L647 (2004)
[28]- Y. P. Wang, L. Zhou, M. F. Zhang, X. Y. Chen, J. M. Liu and Z. G. Liu, “Room-temperature saturated ferroelectric polarization in BiFeO3 ceramics synthesized by rapid liquid phase sintering” Appl. Phys. Lett. 84 , 1731 (2004)
[29]- B. Ruette, S. Zvyagin, A. P. Pyatakov, A. Bush, J. F. Li, V. I. Belotelov, A. K. Zvezdin, and D. Viehland, “Magnetic-field-induced phase transition in BiFeO3 observed by high-field electron spin resonance: Cycloidal to homogeneous spin order” Phys. Rev. B 69, 064114 (2004)
[30]- J. F. Scott, “Ferroelectric Memories” chap.12
[31]- B. E. Park, S. Shouriki, E. Tokumitsu and H. Ishiwara, “Fabrication of PbZrxTi1-xO3 Films on silicon substrates using Y2O3 buffer layers” Jpn. J. Appl. Phys. 37 pp.5145 (1998)
[32]- P. C. Juan, C. Y. Chang, and Y. M. Lee “A New Metal–Ferroelectric (PbZr0.53Ti0.47O3)–Insulator (Dy2O3)–Semiconductor (MFIS) FET for nonvolatile memory applications” IEEE ELECTRON DEVICE LETT. VOL. 27,217 (2006)
[33]- D. Ito, T. Yoshimura, N. Fujimura, T. Ito “Improvement of Y2O3/Si interface for FeRAM application” Applied Surface Science 159-160 138-142 (2000)
[34]- P. C. Juan, Y. P. Hu, F. C. Chiu, and Y. M. Lee “The charge trapping effect of metal-ferroelectric (PbZr0.53Ti0.47O3)-insulator(HfO2)-silicon capacitors” J. Appl. Phys. 98, 044103 (2005)
[35]- H. S. Choi, E. H. Kim, I. H. Choi, Y. T. Kim, J. H. Choi, J. Y. Lee “The effect of ZrO2 buffer layer on electrical properties in Pt/SrBi2Ta2O9/ZrO2/Si ferroelectric gate oxide structure” Thin Solid Films 388 226-230 (2001)
[36]- G.D. Wilk R.M. Wallace and J.M. Anthony “Hafnium and zirconium silicates for advanced gate dielectrics” J.Appl.Phys 87 484(2000)
[37]- DIETER K.SCHRODER “SEMICONDUCTOR MATERIAL AND DEVICE CHARACTERIZATION 2ND EDITION”p349
[38]- K. S. K. Kwa, S. Chattopadhyay, N. D. Jankovic, S. H. Olsen, L. S. Driscoll1 and A. G. O’Neill “Amodel for capacitance reconstruction from measured lossy MOS capacitance–voltage characteristics” Semicond. Sci. Technol.18 82-87 (2003)
[39]- S. Mudanai, F. Li, S. B. Samavedam, P. J. Tobin, C. S. Kang, R. Nieh, J. C. Lee, L. F. Register and S. K. Banerjee “Interfacial defect states in HfO2 and ZrO2 nMOS capacitors” IEEE ELECTRON DEVICE LETTERS, VOL.23, NO.12, DECEMBER (2002)
[40]- W. P. Bai, N. Lu, and D.-L. Kwong “Si interlayer passivation on germanium MOS capacitors with high-_ dielectric and metal gate” IEEE ELECTRON DEVICE LETTERS, VOL.26, NO.6, JUNE (2005)