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博碩士論文 etd-0730102-172555 詳細資訊
Title page for etd-0730102-172555
論文名稱
Title
鐵電材料在元件上製程整合與研究
Study of Ferroelectric Devices Integration
系所名稱
Department
畢業學年期
Year, semester
語文別
Language
學位類別
Degree
頁數
Number of pages
44
研究生
Author
指導教授
Advisor
召集委員
Convenor

口試委員
Advisory Committee
口試日期
Date of Exam
2002-07-05
繳交日期
Date of Submission
2002-07-30
關鍵字
Keywords
鐵電材料
ferroelectric
統計
Statistics
本論文已被瀏覽 5787 次,被下載 3449
The thesis/dissertation has been browsed 5787 times, has been downloaded 3449 times.
中文摘要
摘要

近年來鐵電記憶體元件在下世代的高度整合性電路中引起很大的注意。其中,隨機存取記憶體(DRAM)中所使用高介電常數的薄膜是廣大的研究與發展。但無論如何,DRAM是揮發性記憶體而且非揮發性記憶體是值得被發展的。有主要兩種非揮發性鐵電記憶體:用鐵電蓄電電容器及金屬-鐵電-(絕緣層)-半導體的場效電晶體(MFISFET)。尤其是,從記憶體在非壞性的讀取方式看來,後者為較好的記憶體元件。然而,有許多朝此方向進行的阻礙的挑戰,此種型式的記憶體有一個不好的介面和矽基板之間,並且保存時間也不長。為了克服這些問題,必須在鐵電薄膜和矽基板之間的阻擋層。
有好的閘極結構的鐵電材料結構Pt/SrBi2Ta2O9/Si3N4/p-Si (100)的MFIS記憶體的電性是被研究。245nm厚的SBT薄膜被旋塗在Si3N4/p-Si (100)的基底接著一分鐘的熱退火分別在溫度700∼800℃。試著再低的工作電壓有著大的記憶視窗,備用在不同超薄的Si3N4緩衝層分別為3.5nm,2nm及0.9nm厚。Si3N4緩衝層是用低壓化學氣相沈積方式除了0.9nm氮化物SixNy薄膜外。從C-V測量的結果0.9nm氮化物SixNy薄膜在退火溫度為750℃、偏壓為5V的情形下記憶視窗大約為0.8V。完整的perovskite結晶構造可以被x-ray繞射量測認定。在持久力上扮演重要的角色的漏電流是比2.5 x 10-8 A/cm2 at 200kV/cm SBT用在Pt/SBT (245nm)/ Si3N4 (0.9nm)/p-Si (100)上。其可以達成寫入1010次及超過2小時的持久時間。SBT薄膜可被相信用在進行低電壓的運作、高密度及可能的1T的非揮發性鐵電隨機存取記憶體。



Abstract
Abstract

In recent years ferroelectric memory devices have attracted much attention from the viewpoint of the next generation of highly integrated circuits. Research and development in dynamic random access memory (DRAM) using high dielectric constant films are extensive. However, DRAM is volatile memory, and it is desirable that nonvolatile memory should be developed. There are mainly two kinds of ferroelectric nonvolatile memories: a memory cell using a ferroelectric storage capacitor, and metal-ferroelectric-(insulator)-semiconductor FET (MFISFET). Especially, the latter is superior among memory devices since the memory is read out nondestructively. In practice, however, there are many challenges which have held back the progress in that direction, a major one being the difficulty of making an electrically switchable ferroelectric thin film on Si with good interface properties and long retention time. To overcome these problems, buffer layers are usually inserted between the ferroelectric layer and silicon substrate.

The electrical properties of the MFIS memories with stacked gate configuration of ferroelectric Pt/SrBi2Ta2O9/Si3N4/p-Si (100) were investigated. 245nm-thick SBT thin films were spin-coated on the Si3N4/Si substrate followed by 1 min. rapid thermal crystallization annealing at the temperatures regime of 700~800℃. In an attempt to operate memory at low voltage with sufficient large memory window, various ultra thin Si3N4 buffer layers in thickness of 3.5, 2, and 0.9nm were employed. The Si3N4 buffer layers were deposited by means of LPCVD with the exception of surface nitridation for 0.9nm SixNy thin film. From the results of C-V measurements, the memory window can be as large as 0.8V at the bias amplitude of 5 V for the sample with 0.9 nm SixNy buffer layer and 750℃ annealing temperature. Complete perovskite crystalline structure can also be affirmed by the spectra of X-ray diffraction measurements. The leakage current, which plays a very important role in the data retention, of Pt/SBT (245nm)/ Si3N4 (0.9nm)/p-Si (100) is as low as 2.5 x 10-8 A/cm2 at 200kV/cm. The 1010 write cycles and greater than 2hr retention time can be achieved. Optimization and scaling of SBT thin films are believed to be effective in pursuing extremely low voltage operation, high-density and liable 1T nonvolatile ferroelectric random access memories.



目次 Table of Contents
CONTENTS

ABSTRACT (in Chinese) i
ABSTRACT (in English) iii
ACKNOWLEDGEMENT v
CONTENTS vi
TABLE CAPTIONS viii
FIGURE CAPTIONS ix

Chapter 1
Introduction 1
1-1 General Background 1
1-2 Motivation 3
1-3 Thesis Organization 4

Chapter 2
Characteristics of ferroelectrics 5
2-1 Ferroelectricity 5
2-1.1 Ferroelectric hysteresis loop 6
2-1.2 Dielectric and ferroelectric theory 8
2-2 Ferroelectric memory 9
2-2.1 Type of ferroelectric memory 9
2-2.2 Operation mechanism 11
2-2.3 Scaling Rule of Ferroelectric Memories 12
2-3 Reliability 13
2-3.1 Fatigue 14
2-3.2 Retention 15
2-3.3 Imprint 16
2-3.4 Leakage current 17

Chapter 3
Experimental details 19
3-1 Experimental proces 19
3-2 Physical Characterization Techniques 20
3-2.1 X-Ray Diffraction Analysis (XRD) 20
3-2.2 Atomic force microscopy (AFM) 21
3-2.3 Scanning Electron Microscopy(SEM) 21
3-3 Electrical Characterization Techniques 21
3-3.1 Current-voltage (I-V) measurements 21
3-3.2 Capacitance-voltage (C-V) measurements 21
3-3.3 Fatigue Meausrements 22
Chapter 4
Results and discussion 23
4-1 Effect of substrate temperature on properties of SBTN films 23
4-2 The MFIS Structure 23
4-3 Reliability studies of SBT films 27
4-3.1 Retention Characteristics 27
4-3.2 Fatigue Characteristics 28
Chapter 5
Conclusions 29
參考文獻 References
References
[1] S. L. Miller and P. J. McWhorter, “Physics of the ferroelectric nonvolatile memory field effect transistor,” Jpn. J. Appl. Phys.72(12), 15 December 1992
[2] Y.Shichi, S. Tanimoto, T. Goto, K. Kuroiwa, Y.Tarui, “Interaction of PbTiO3 films with Si substrate,” Jpn. J. Appl. Phys., vol. 33, No. 9B, pp. 5172-5177, 1994
[3] Gary F. Derbenwick and Alan F. Isaacson, “Ferroelectric memory: On The Brink of Breaking Through,” IEEE CIRCUIT & DEVICES, pp. 20-30, January 2001
[4] J.Robertson and C.W. Chen, W. L. Warren, and C. D. Gutleben, “Electronic structure of the ferroelectric layered perovskite SrBi2Ta2O9,” Appl. Phys. Lett., vol.69, pp. 1704-1706, September 1996
[5] Huei-Mei Tsai, Pang Lin, and Tseung-Yuen Tseng, “Effect of bismuth content on the properties of Sr0.8BixTa1.2Nb0.9O9+y ferroelectric thin films,” J. Appl. Phy., vol. 85, pp. 1095-1100, January 1999
[6] Di Wu, Aidong Li, Juiqin Ling, Tao Yu, Zhiguo Liu, and Naiben Ming, “Characterization of metalorganic decomposition-derived SrBi2Ta2O9 thin films with different thickness,” J. Apll. Phys., vol. 87, pp. 1795-1800, February 2000
[7] S. B. Desu, P. C. Joshi, S. O. Ryu, “Thin films of layered-structure (1-x)SrBi2Ta2O9-xBi3TI(Ta1-yNby)O9 solid solution for ferroelectric random access memory devices,” Appl. Phys. Lett., vol. 71, pp. 1041-1043, June 1997
[8] Jin-Ping Han and T. P. Ma, Appl. Phys. Lett. 72 (1998) 1185
[9] Minoru Noda, Yoshinori Mstsumudo, Hideki Sugiyama, and Masanori Okuyama, Jpn. J. Appl. Phy., 38 (1999) pp. 2275-2280
[10] Kyu-Jeong Choi, Woong-Chul Shin, Jung-Hwan Yang, and Soon-Gil Yoon, Appl. Phys. Lett. 75 (1999) 722
[11] Daniel M. Fleetwood, Senior Member, “Border Traps in MOS Devices,” IEEE Transactions on Nuclear Science, vol. 39, No. 2, pp. 269-271, April 1992
[12] Laureen H. Parker and Al F. Tasch, “Ferroelectric Materials For 64Mb and 256 Mb DRAMs,” IEEE CIRCUIT DEVICES, pp.17-26, January 1990
[13] W. P. Li, r. Zhang, J. Shen, Y. M. Liu, B. Shen, P. Chen, Y. G. Zhou, J. Li, X. L. Yuan, Z. Z. Chen, Y. Shi, Z. G. Liu, and Y. D. Zheng, “Evidence for ferroelectric border traps near the SrBi2Ta2O9/Si interface through capacitance-voltage measurement,” Appl. Phys. Lett., vol. 77, pp. 564-566, July 2000
[14] N. Tanable, S. Kobayashi, T. Miwa, K. Amanuma, H. More, N. Inoue T. Takeuchi, S.Saitoh, Y. Hayashi, J. Yamada, H. Koike, H. Hada and T. Kunio, “High Tolerance Operation of 1T/2C FeRAMs for the Variation of cell Capacitors Characteristics,” IEEE Symposium on VLSI Technology Digest of Technical Papers, pp. 124-125, 1998
[15] Si-Bei Xiong and Shigeki Sakai, “Memory Properties of SrBi2Ta2O9 thin films prepared on SiO2/Si substrates,” Appl. Phys. Lett., vol. 75, pp. 1613-1615, September 1999
[16] Won-Jae Lee, Chang-Ho Shin, Chae-Ryong Cho, Jong-Sun Lyu, Bo-Woo Kin, Byong-Gon Yu and Kyoung-Ik Cho, “Electrical Properties of SrBi2Ta2O9/Insulator/Si Structures with Various Insulators,” Jpn. J. Appl. Phys. ,Vol. 38, pp. 2039-2043, April 1999
[17] Tadahiko Hirai, Kazuhiro Teramoto, Kazuhito Nagashima, Hiroshi Koike, Shinya Matsuno, Satoshi Tanimoto and Yasuo Tarui, “Crystal and Electric Characterizations of Oriented Yttia-Stabilized Zirconia Buffer Layer for the Metal/Ferroelectirc/Insulator/Semiconductor Field-Effect Transistor,” Jpn. J. Appl. Phys., vol. 35, pp. 4016-4020, July 1996
[18] Takeshi Yamaguchi, Masato Koyama, Akira Takashima and Shin-ichi Takagi, “Improvement of Memory Characteristics of Metal-Ferroelectrics/Insulating Buffer Layer/Semiconductor Structures by Combination of Pulsed laser Deposited SrBi2Ta2O9 Films and Ultra-Thin SiN Buffer Layers,” Jpn. J. Appl. Phys., vol. 39, pp.2058-2062, April 2000.
[19] Yong Tae Kim, Dong Suk Shin, Young K. Park, and In-Hoon Choi, “Effects of Bi-Pt alloy on electrical characteristics of Pt/SrBi2Ta2O9/CeO2/Si ferroelectric gate structure,” J. Appl. Phys., vol. 86, pp. 3387-3390, September 1999
[20] Toshiyuki KAWASAKI, Yoshikazu AKIYAMA, Shunsuke FUJITA, and Shiro SATOH, Nonmembers, “MFMIS Structure for Novolatile Ferroelectric Memory Using PZT Thin Film,” IEICE TRANS. ELECTRON. vol. E81-C, No.4, pp. 584-589, April 1998
[21] Eisuke Tokumitsu, Gen Fujii and Hiroshi Ishiwara, “Nonvolatile ferroelectric-gate field-effect transistors using SrBi2Ta2O9/Pt/SrTa2O6/SiON/Si structures,” Appl. Phys. Lett., vol. 75, pp. 575-577, July 1999
[22] Eisuke Tokumitsu, Gen Fujii and Hiroshi Ishiwara, “Electrical Properties of Metal- Ferroelectric- Insulator- Semiconductor(MFIS) and Metal-Ferroelectric-Metal-Insulator-Semiconductor (MFMIS)-FETs Using Ferroelectric SrBi2Ta2O9 Film and SrTa2O6/SiON Buffer Layer,” Jpn. J. Appl. Phys., vol. 39, pp. 2125-2130, April 2000
[23] Eisuke Tokumitsu, Gen Fujii and Hiroshi Ishiwara, “Low Voltage Operation of Nonvolatile Metal-Ferroelectric-Metal-Insulator-Semiconductor(MFMIS) –Field -Effect-Transistors (FETs) Using Pt / SrBi2Ta2O9 / Pt / SrTa2O6 / SiON / Si Structures,” Jpn. J. Appl. Phys., vol. 40, pp. 2917-2922, April 2001
[24] Y. Fujimori, T. Nakamura and A. Kamisawa, “Properties of Sr2Nb2O7 Family Ferroelectric Thin Films,” IEEE, pp, 55-58, 1998
[25] Eisuke Tokumitsu, Ryo-ichi Nakamur, and Hiroshi Ishiwara, “Nonvolatile Memory Operations of Metal-Ferroelectric-Insulator-Semiconductor (MFIS) FET’s Using PLZT/STO/Si(100) Structures,” IEEE ELECTRON DEVICE LETTERS, vol. 18, No. 4, pp. 160-162, April 1997
[26] Stephen C. Philpy, David A. Kamp, Alan D. Deviliss, Alan F. Isaacson and Gary F. Derbenwick, “Ferroelectric Memory Technology for Aerospace Applications,” IEEE, pp. 377-383, 2000
[27] Y. T. Kim, C. W. Lee, D. S. Shin and H. N. Lee, “Effect of Insulator on Memory Window of Metal-Ferroelectric-Insulator-Semiconductor-Field Effect Transistor (MEFISFET)-Non Destructive Readout Memory Devices,” IEEE, pp. 35-38, 1998
[28] Takahiro Hanyu, Hiromitsu Kimura and Michitaka Kameyama, “Multiple- Valued Content-Addressable Memory Using Metal-Ferroelectric-Semiconductor FETs,” IEEE, pp. 30-35, 1999
[29] Yasuo TARUI, “Future DRAM Development and Prospects for Ferroelectric Memories,” IEDM, pp. 1.2.1-1.2.10, 1994
[30] D. Dimos, W. L. Warren, M. B. Sinclair, B. A. Tuttle, and R. W. Schwartz, “Photoinduced hysteresis changes and optical storage in (Pb, La)(Zr,Ti)O3 thin films and ceramics,” J.Appl. Phys., vol. 76. Pp. 4305-4315, October 1994
[31] Z. G. Zhang, J. S. Liu, Y. N. Wang, J. S. Zhu, J. L. Liu. D. Su, and H. M. Shen, “Structure and voltage dependence of ferroelectric properties of SrBi2Ta2O9 thin films,” J. Appl. Phys. vol. 85, pp. 1746-1749, February 1999
[32] J. Robertson , C. W. Chen, W. L. Warren, and C. D. Gutleben, “Electronic structure of the ferroelectric layered perovskite SrBi2Ta2O9,” Appl. Phys. Lett., vol. 69, pp. 1704-1706, September 1996
[33] X. B. Chen, F. Yan., C. H. Li, Z. G. Zhang, J. S. Zhu, and Y. N. Wang, “Switching properties of SrBi2Ta2O9 thin films produced by metalorganic decomposition,” Appl. Phys. Lett., vol. 76, pp. 369-371, January 2000
[34] H. N. Al-Shareef, D. Dimos, T. J. Boyle, W. L. Warren, and B. A. Tuttle, “Qualitative model for the fatigue-free behavior of SrBi2Ta2O9,” Appl. Phys. Leet. vol. 68, pp. 690-692, January 1996
[35] Z. G. Zhang, J. S. Liu, Y. N. Wang, J. S. Zhu, F. Yan, X. B. Chen, and H. M. Shen, “Fatigue characteristics of SrBi2Ta2O9 thin films prepared by meralorganic decomposition,” Appl. Phys. Lett. vol. 73, pp. 788-790, August 1998
[36] Akira Furuya, and JoeD. Cuchiaro, “Compositional dependence of electrical characteristics of SrBi2(Ta1-xNbx)2O9 thin-film capacitors,” J. Appl. Phys., vol.84, pp. 6788-6794, December 1998
[37] Kazushi Amanuma, Takashi Hase, and Yoichi Miyasaka, “Preparation and ferroelectric properties of SrBi2Ta2O9 thin films,” Appl. Phys. Lett., vol.66, pp. 221-223, January 1995
[38] A. Gruverman, and M. Tanaka, “Polarizaion retention in SrBi2Ta2O9 thin films investigated at nanoscale,” J. Appl. Phys., vol. 89, pp. 1836-14843, February 2001
[39] Y. Shimada, K. Nakao, A. Inoue, M . Azuma, Y. Uemoto, E. Fujii, and T. Otsuki, “Temperature effects on charge retention characteristics of integrated SrBi2(Ta,Nb)2O9 Capacitors,” Appl. Phys. Lett. vol. 27, pp. 2538-2540, October 1997
[40] San-Yuan Chen and Ving-Ching Lee, “Aging behavior and recovery of polarizarion in Sr0.8Bi2.4Ta2O9 thin films,” J. Appl. Phys., vol. 87, pp. 3050-3055, March 2000
[41] Yasuhiro Shinada, asamichi Azuma, Keisaku Nakao, Shigeo Chaya, Nobuyuki Moriwaki and Tatsuo Otsuki, “Retention Characteristics of a Ferroelectric Memory based on SrBi2(Ta,Nb)2O9,” Jpn. J. Appl. Phys., vol. 36, pp. 5912-5916, September 1997
[42] Mitsue Takahashi, Hideki Sugiyama, Toshiyuki Nakaiso, Kazushi Kodama, Minoru Noda and Masanori Okuyana, “Analysis and Improvement of Retention Time of Memorized State of Metal-Ferroelectric-Insulator-Semiconductor Structure for Ferroelectric Gate FET Memory,” Jpn. J. Appl. Phys., vol. 40, pp. 2923-2927, April 2001
[43] Takashi Hase, Takehiro Noguchi, Koichi Takemura and Yoichi, “Imprint Characteristics of SrBi2Ta2O9 Thin Films with Modified Sr Composition,” Jpn. J. Appl. Phys. vol. 37, pp. 5198-5202, September 1998
[44] H. N. Al-Shareef, D. Dimos, W. L. Warren, and B. A. Tuttle, “Voltage offsets and imprint mechanism in SrBi2Ta2O9 thin films,” J. Appl. Phys., pp. 4573-4577, October 1996
[45] M. GROSSMANN, O. LOHSE, D. BOLTEN, and R. WASER, “Imprint in Ferroelectric SrBi2Ta2O9 Capacitors For Non-Volatile Memory Applications,” Integrated Ferroelectric, vol. 22, pp. 95-107, 1998
[46] W. L. Warren, H. N. AL-Shareef, D. Dimos, B. A. Tuttle, and G. E. Pike, “Driving force behind voltage shifts in ferroelectric materials,” Appl. Phys. Lett., vol. 68, pp. 1681-1683, March 1996
[47] H. Hu and S. B. Krupanidhi, “Current-voltage characteristics of ultrafine-grained ferroelectric Pb(Zr, Ti)O3 thin films,” J. Mater. Res., vol. 9, pp. 1484-1498, 1994
[48] Koji Watanabe, Andreas J, Hartmann, Robert N. Lamb and James F. Scott, “A Comoarison of Schottky-Limited and Space-Charge-Limited Currents in SrBi2Ta2O9 Thin Films,” Integrated Ferroelectric, vol. 21, pp. 241-249, 1998
[49] Won-Jar Lee, Chang-Ho Shin, Chae-Ryong Cho, Jong-Sun Lyu, Bo-Woo Kim, Jpn. J. Appl. Phy. 38 (1999) pp. 2039-2043
[50] Kyu-Jeong Choi, Woong-Chul Shin, Jung-Hwan Yang, and Soon-Gil Yoon, Appl. Phys. Lett. 75 (1999) 722
[51] Takeshi Yamaguhi, Masato Koyama, Akira Takashima, and Shin-ichi Takagi, Jpn. J. Appl. 39 (2000) pp. 2058-2062
[52] Takeshi Kanashima and Masanori Okuyama, Jppn. J. Appl. Phys. 38 (1999) pp. 2044-2048
[53] Joo Dong Park, Ji Woong Kim, and Tae Sung Oh, Applications of Ferroelectrics, 2000. ISAF 2000. Proceedings of the 2000 12th IEEE International Symposium on 2 (2001) 637
[54] Minoru Noda, Yoshinori Mstsumudo, Hideki Sugiyama, and Masanori Okuyama, Jpn. J. Appl. Phy., 38 (1999) pp. 2275-2280
[55] Ho Nyung Lee, Yong Tae Kim, and Sung Ho Choh, “Comparison of memory effect between YMnO3 and SrBi2Ta2O9 ferroelectric thin films deposited on Si substrates,” Appl. Phys. Lett., vol. 76, pp. 1066-1068,2000
[56] MYOUNGHO LIM and T.S. KALKUR, "The role of buffer layer in strontium bismuth tantalate based ferroelectric gate mos structures for non-volatile destructive read out memory applications," Integrated Ferroelectrics, vol. 17, pp.433-441,1997
[57] S.Y.Wu., "A new ferroelectric memory device, metal ferroelctric semiconductor transistor,",IEEE Trans. Electron Devices, ED-21,8,499,1974
[58] Takeshi KANASHIMA* and Masanori QKUYAMA, "Analysis of high Frequency Capacitance-Volatage Characteristics of Metal-Ferroelectric-Insulator-Silicon Structure," Jpn. J. Appl. Phys. vol. 38, pp.2044-2048, 1999

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