The Effects of Plasma Treatments on the Field Emission Characteristics of Silicon Nanowires 詹凱傑、李世鴻

(1)

The Effects of Plasma Treatments on the Field Emission Characteristics of Silicon Nanowires 詹凱傑、李世鴻

ABSTRACT

Silicon nanowires have been synthesized on Si substrate (100) via a Ni catalytic reaction in Ar ambience at 1000 °C for 2hr. and, the as grown silicon nanowires were treated with various plasmas for the analyses of SiNW on field emission characteristics. It must be noted that the field emissiom current of as-grown SiNW is much smaller than that of carbon nanotubes. Nevertheless, after the hydrogen plasma treatment, the screen effect of the SiNW was reduced and the electronic emissions from the surface of SiNW film were aided effectively. The SiNW will clusted together after treatment of CF4 plasma, the appearance of cluster can increase the surface density and emission sites of SiNW. Additionly, in SiNW, after CF4+H2 plasma treatment, not only the screen effect will be reduced, but also the surface density and emission sites will be increaded dramatically.

In summary, after plasma treatment, the field emission characteristics of SiNWs were impoved obviously, and could be match against that of carbon nanotubes. The SiNW can provide much potential for field emission application.

Keywords : Silicon nanowires (SiNW)、Field emission、plasma、Screening effect Table of Contents

封面內頁簽名頁

授權書...iii

中文摘要...iv

ABSTRACT...v

誌謝...vi

目錄...vii

圖目錄...x

表目錄...xiv

第一章、簡介...1

1.1 奈米材料的歷史與簡介...1

1.2 奈米材料的特徵...4

1.2.1 表面效應...4

1.2.2小尺寸效應...5

1.2.3量子穿隧效應...7

1.3 奈米材料的應用...9

1.3.1 場發射電子源...12

1.3.2 場發射電子源的特性...12

第二章、文獻回顧...14

2.1 氫氣電漿處理文獻...14

2.2 氫氣退火處理文獻...20

2.3 研究動機...23

第三章、理論與研究方法...25

3.1 電子場發射理論...25

3.2 奈米線的成長機制...28

3.2.1 Vapor-Liquid-Solid (VLS)...29

3.2.2 氧化物輔助生長 (Oxide-Assisted Growth, OAG)...31

3.2.3 Vapor-Solid (VS)...33

3.2.4 Solution-Liquid-Solid...34

3.2.5 Solid-Liquid-Solid (SLS)...36

(2)

3.2.6 Solid-Solid transformation (SS)...38

3.3 電漿蝕刻機制...39

3.4 實驗儀器原理...40

3.4.1 熱蒸鍍系統...40

3.4.2 高溫爐管系統...41

3.4.3 電漿蝕刻系統...42

3.4.4 掃描式電子顯微鏡系統...45

3.4.5 能量散佈分析儀系統...46

3.4.6 場發射量測裝置系統...48

3.5 實驗步驟...50

3.5.1 蒸鍍...50

3.5.2 成長矽奈米線...51

3.5.3 電漿後處理...52

3.5.4 電性量測...52

第四章、實驗結果與討論...53

4.1 CF4電漿後處理對矽奈米線的研究與討論...53

4.1.1 掃瞄式電子顯微鏡(SEM)的分析...53

4.1.2 能量散佈分析儀(EDS)的分析...57

4.1.3 電子場發射的分析...59

4.2 H2電漿後處理對矽奈米線的研究與討論...64

4.3 CF4+H2電漿後處理對矽奈米線的研究與討論...72

4.4 不同電漿處理對矽奈米線的研究與討論...82

4.4.1 掃瞄式電子顯微鏡(SEM)的分析比較...82

4.4.2 能量散佈分析儀(EDS)的分析比較...83

4.4.3 電流密度的分析比較...84

第五章、結論...86

參考文獻...87 REFERENCES

[1]A. S. Edelstein, and R. C. Cammarata, Chap. 1 in Nanomaterails: Synthesis, Properties and Applications, Ed. by A. S. Edelstein and R. C.

Cammarata, IOP Publishing. (1996).

[2]H. W. Kroto, J. R. Heath, S. C. O’Brian, R. F. Curl, and R. E. Smalley, C60: Buckminsterfullerene, Nature, 318, 162-163 (1985).

[3]W. Kratschmer, L. D. Lamb, K. Fostiropoulos, and D. R. Huffman, C60: A new form of carbon, Nature, 347, 354-358 (1990).

[4]A. Maiti, C. J., Brabec, C. Roland, and J. Bernholc, Theory of carbon nanotube growth, Phys. Rev. Lett., 52, 14850-14858 (1995).

[5]曹茂盛等編著，奈米材料導論，學富文化事業有限公司，2004年。

[6]T. C. Cheng, A. J. Shieh, W. J. Huang, M. C. Yang, M. H. Cheng, H. M. Lin, and M. N. Chang, Hydrogen plasma dry etching method for field emission application, Appl. Phys. Lett., 88, 263118 (2006).

[7]D. Whang, S. Jin, Y. Wu, and C. M. Lieber, Large-scale hierarchical organization of nanowire arrays for integrated nanosystems, Nano Lett., 3, 1255-1259 (2003).

[8]J. Xiang, W. Lu, Y. Hu, Y. Wu, H. Yan, and C. M. Lieber, Ge/Si nanowire heterostructures as high performance field-effect transistors, Nature, 441, 498-493 (2006).

[9]F. C. K. Au, K. W. Wong, Y. H. Tang, Y. F. Zhang, I. Bello, and S. T. Lee, Electron field emission from silicon nanowires, Appl. Phys. Lett., 75, 1700 (1999).

[10]S. T. Purcell, V. T. Binh, and N. Garcia, 64 meV measured energy dispersion from cold field emission nanotips, Appl. Phys. Lett., 67, 436-438 (1995).

[11]W. A. Deheer, A. Chatelain, and D. Ugarte, A carbon nanotube field-emission electron source, Science, 270, 1179-1180 (1995).

(3)

[12]Iijima S. Helical microtubules of graphitic carbon, Nature, 354, 56-58 (1991).

[13]李元?、何?、唐先忠等，納米氧化錫的製程與特性測試，實驗科學與技術，1, 61-62 (2003)。

[14]田時開、江天府、楊興華、曾葆青，碳納米管薄膜的製程及處理對場發射特性的影響，電子科技大學學報，第36卷，第6期

，936-938頁，2006年。

[15]N. D. Jonge, Y. Lamy, and K. Schoots, High brightness electron beam from a multi-walled carbon nanotube, Nature, 420, 393-395 (2002).

[16]張兆祥、張耿明、侯士敏等。碳納米管的薄膜場發射。真空科學技術學報，23卷，27-32頁，2003年。

[17]Allon I. Hochbaum, Renkun Chen, Raul Diaz Delgado, Wenjie Liang, Erik C. Garnett, Mark Najarian, Arun Majumdar, Peidong Yang, Enhanced thermoelectric performance of rough silicon nanowires, Nature, 451, 163-167 (2008).

[18]N.N. Dzbanovsky, V.V. Dvorkin, V.G. Pirogov, N.V. Suetin, The aligned Si nanowires growth using MW plasma enhanced CVD, Microelectronics Journal, 36, 634-638 (2005).

[19]D.M. Todorovic, M. Smiljanic, M. Sarajlic, D. Vasiljevic-Radovic, D. Randjelovic, Investigation of the effects of Ar plasma etching in Si surface by photoacoustic method, J. Phys, 125, 451-453 (2005).

[20]Yu-Fen Tzeng, Yen-Chih Lee, Chi-Young Lee, Hsin-Tien Chiu, I-Nan Lin, Electron field emission properties on UNCD coated Si-nanowires, Diamond and Related Materials, 17, 753-757 (2008).

[21]B. Zeng, G. Xiong, S. Chen, S. H. Jo, W. Z. Wang, D. Z. Wang, and Z. F. Ren, Field emission of nanowires, Appl. Phys. Lett., 88, 213108 (2006).

[22]T. C. Cheng, J. Shieh, W. J. Huang, M. C. Yang, and M. H. Cheng, Hydrogen plasma dry etching method for field emission application, Appl. Phys. Lett., 88, 263118 (2006).

[23]M. J. Yang, J. Shieh, S. L. Hsu, I. J. Huang, C. C. Leu, S. W. Shen, T. Y. Huang, P. Lehnen, and C. H. Chien, Low-temperature growth of polycrystalline Ge films on SiO2 substrate by HDPCVD, Electrochem. Solid-State Lett., 8, C74 (2005).

[24]楊閔智、謝健、許瓊姿、鄭宗杰，以氫電漿乾式蝕刻法製作準直矽奈米草陣列，奈米通訊，第十二卷第三期，44-49頁，2007年。

[25]M. C. Yang, J. Shieh, C. C. Hsu, and T. C. Cheng, Well-aligned silicon nanograss fabricated by hydrogen plasma dry etching, Electrochem.

Solid-State Lett., 8, C131-C133 (2005).

[26]J. M. Bonard, K. A. Dean, B. F. Coll, and C. Klinke, Field emission of individual carbon nanotubes in the scanning electron microscope, Phys.

Rev. Lett., 89, 197602 (2002).

[27]C. J. Lee, T. J. Lee, S. C. Lyu, and Y. Zhang, Field emission from well-aligned zinc oxide nanowires grown at low temperature, Appl. Phys.

Lett., 81, 3648-3650 (2002).

[28]B. Zeng, G. Xiong, S. Chen, S. H. Jo, W. Z. Wang, D. Z. Wang, and Z. F. Ren, Field emission of nanowires, Appl. Phys. Lett., 88, 213108 (2006).

[29]C. A. Spindt, I. Brodie, L. Humphrey, and E. R. Westerberger, Physical properties of thin-film field emission cathodes with molybdenum cones, J. Appl. Phys. Lett., 47, 5248-5263 (1976)[30]W. Zhu, Vacuum Microelectronics, Wiley, New York (2001).

[31]N. S. Xu, and S. Ejaz Huqb, Metal-oxide interfaces, Mater. Sci. Eng., R. 48, 47 (2005).

[32]Y. B. Li, Y. Bando, D. Golberg, and K. Kurashima, Field emission from MoO3 nanobelts, Appl. Phys. Lett., 81, 5048 (2002).

[33]Y. Tu, Z. P. Huang, D. Z. Wang, J. G. Wen, and Z. F. Ren, Growth of aligned carbon nanotubes with controlled site density, Appl. Phys.

Lett., 80, 4018-4020 (2002).

[34]G. Z. Yue, Q. Qiu, B. Gao, Y. Cheng, J. Zhang, H. Shimoda, S. Chang, J. P. Lu, and O. Zhou, Generation of continuous and pulsed diagnostic imaging x-ray radiation using a carbon-nanotube-based field-emission cathode, Appl. Phys. Lett., 81, 355-357 (2002).

[35]C. S. Hsieh, G. Wang, D. S. Tsai, R. S. Chen, and Y. S. Huang, Field emission characteristics of ruthenium dioxide nanorods, Nanotechnology, 16, 1885-1891 (2005)[36]J. Zhou, L. Gong, S. Z. Deng, J. Chen, J. C. She, N. S. Xu, R. Yang, and Z. Wang, Growth and field-emission property of tungsten oxide nanotip arrays, Appl. Phys. Lett., 87, 223108 (2005).

[37]Y. H. Tang, X. H. Sun, F. C. K. Au, L. S. Liao, H. Y. Peng, C. S. Lee, S. T. Lee, and T. K. Sham, Microstructure and field-emission characteristics of boron-doped Si nanoparticle chains, Appl. Phys. Lett., 79, 1673-1675 (2001).

[38]M. Lu, M. K. Li, L. B. Kong, X. Y. Guo, and H. L. Li, Synthesis and characterization of well-aligned quantum silicon nanowires arrays, Composites, 35, 179-184 (2004).

[39]A. M. Morales, and C. M. Lieber, A laser ablation method for the synthesis of crystalline semiconductor nanowires, Science, 279, 208-211 (1998).

[40]H. F. Yan, Y. J. Xing, Q. L. Hang, D. P. Yu, Y. P. Wang, J. Xu, Z. H. Xi, and S. Q. Feng, Growth of amorphous silicon nanowires via a solid-liquid-solid mechanism, Chem. Phys. Lett., 323, 224-228 (2000).

[41]S. T. Lee, Y. F. Zhang, N. Wang, Y. H. Tang, I. Bello, C. S. Lee, and Y. W. Chung, Semiconductor nanowires from oxides, Mater. Res., 14, 4503-4507 (1999).

[42]C. N. R. Rao, F. L. Deepak, G. Gundiah, and A. Gorindarj, Inorganic nanowires, Prog. Solid State Chem., 31, 5 (2003).

[43]R. S. Wagner, and W. C. Ellis, Vapor-liquid-solid mechanism of single crystal growth, Appl. Phys. Lett., 4, 89-90 (1964).

[44]R. S. Wagner, in Whisker Technology, Ed. A. P. Levitt, Wiley New York, 47-119 (1970).

(4)

[45]Y. Wu and P. Yang, Direct observation of vapor-liquid-solid nanowire growth, J. Am. Chem. Soc., 123, 3165-3166 (2001).

[46]Y. W. Wang, C. H. Liang, G. W. Meng, X. S. Peng, and L. D. Zhang, Synthesis and photoluminescence properties of amorphous SiOx nanowires, J. Matter. Chem., 12, 651-653 (2002).

[47]D. P. Yu, Q. L. Hang, Y. Ding, H. Z. Zhang, Z. G. Bai, J. J. Wang, Y. H. Zou, W. Qian, G. C. Xiong, and S. Q. Feng, Amorphous silica nanowires: Intensive blue light emitters, Appl. Phys. Lett., 73, 3076-3078 (1998).

[48]H. F. Zhang, C. M. Wang, Edgar C. Buck, and L. S. Wang, Synthesis, characterization, manipulation of helical SiO2 nanosprings, Nano Lett., 3, 577-580 (2003).

[49]X. C. Wu, W. H Song, K. Y. Wang, T. Hu, B. Zhao, Y. P. Sun, and J. J. Du, Preparation and photoluminescence properties of amorphous silica nanowires, Chem. Phys. Lett., 336, 53-56 (2001).

[50]Y. J. Chen, J. B. Li, Y. S. Han, Q. M. Wei, and J. H. Dai, A novel morphology of SiOx nanowires with a modified diameter, Appl. Phys. Lett., 74, 433-435 (2002).

[51]J. C. Wang, C. Z. Zhan, and F. G. Li, The synthesis of silica nanowire arrays, Solid State Commun., 125, 629-631 (2003).

[52]Z. W. Pan, Z. R. Dai, C. Ma, and Z. L. Wang, Molten gallium as a catalyst for the large-scale growth of highly aligned silica nanowires, J. Am, Chem. Soc., 124, 1817-1822 (2002).

[53]S. H. Sun, G. W. Meng, M. G. Zhang, Y. T. Tian, T. Xie, and L. D. Zhang, Preparation and characterization of oriented silica nanowires, Solid State Commun., 128, 287-290 (2003).

[54]J. Hu, Y. Bando, J. Zhan, X. Yuan, T. Sekiquchi, and D. Golberg, Self-assembly of SiO2 nanowires and Si microwires into hierarchiral heterostructures on a large scale, Adv. Mater., 17, 971-975 (2005).

[55]S. T. Lee, N. Wang, Y. F. Zhang, and Y. H. Tang, Oxide-assisted semiconductor nanowire growth, MRS Bull., 24, 36-42 (1999).

[56]S. T. Lee, Y. F. Zhang, N. Wang, Y. H. Tang, I. Bello, C. S. Lee, Y. W. Chung, and Y. W. Chung, Semiconductor nanowires from oxides, J.

Mater. Res., 14, 4503-4507 (1999).

[57]N. Wang, Y. H. Tang, Y. F. Zhang, C. S. Lee, and S. T. Lee, Nucleation and growth of Si nanowires from silicon oxide, Phys. Rev., 58, R16024-R16026 (1998).

[58]T. S. Chu, R. Q. Zhang, and H. F. Cheung, Geometric and electronic structures of silicon oxide clusters, J. Phys. Chem., 105, 1705-1709 (2001).

[59]R. Q. Zhang, Y. Lifshitz, and S. T. Lee, Oxide-assited growth of semiconducting nanowires, Adv. Matter, 15, 635-640 (2003).

[60]X. M. Meng, J. Q. Hu, Y. Jiang, C. S. Lee, and S. T. Lee, Oxide-assisted growth and characterization of Ge/SiOx nanocables, Appl. Phys.

Lett., 83, 2241-2243 (2003).

[61]Y. Cui, L. J. Lauhon, M. S. Gudiksen, J. F. Wang, and C. M. Lieber, Diameter-controlled synthesis of single-crystal silicon nanowires, Appl.

Phys. Lett., 78, 2214-2216 (2001).

[62]G. W. Zhou, H. Li, H. P. Sun, D. P. Yu, Y. Q. Wang, X. J. Huang, L. Q. Chen, and Z. Zhang, Controlled Li doping of Si nanowires by electrochemical insertion method, Appl. Phys. Lett., 75, 2447-2249 (1999).

[63]D. D. D. Ma, C. S. Lee, F. C. K. Au, S. Y. Tong, and S. T. Lee, Small-diameter silicon nanowire surfaces, Science, 299, 1874-1877 (2003).

[64]Y. F. Zhang, Y. H. Tang, N. Wang, C. S. Lee, I. Bello, and S. T. Lee, Germanium nanowires sheathed with an oxide layer, Phys. Rev., 61, 4518-4521 (2000).

[65]W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee, and S. T. Lee, Microstructures of gallium nitride nanowires synthesized by oxide-assisted method, Chem. Phys. Lett., 345, 377-380 (2001).

[66]H. Y. Peng, X. T. Zhou, N. Wang, Y. F. Zheng, L. S. Liao, W. S. Shi, C. S. Lee, and S. T. Lee, Bulk-quantity GaN nanowires synthesized from hot filament CVD, Chem. Phys. Lett., 327, 263-270 (2000).

[67]W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee, and S. T. Lee, A general synthetic route to III-V compound semiconductor nanowires, Adv.

Matter, 13, 591-594 (2001).

[68]W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee, and S. T. Lee, Oxide-assisted growth and optical characterization of gallium-arsenide nanowires, Appl. Phys. Lett., 78, 3304-3306 (2001).

[69]W. S. Shi, Y. F. Zheng, N. Wang, C. S. Lee, and S. T. Lee, Synthesis and microstructure of gallium phosphide nanowires, J. Vac. Sci.

Technol., 19, 1115-1118 (2001).

[70]J. Q. Hu, X. L. Ma, Z. Y. Xie, N. B. Wong, C. S. Lee, I. Bello, and S. T. Lee, Characterization of zinc oxide crystal whiskers grown by thermal evaporation, Chem. Phys. Lett., 344, 97-100 (2001).

[71]Y. H. Tang, N. Wang, Y. F. Zhang, C. S. Lee, I. Bello, and S. T. Lee, Synthesis and characterization of amorphous carbon nanowires, Appl.

Phys. Lett., 75, 2921-2923 (1999).

[72]K. H. Lee, S. W. Lee, R. R. Vanflee, and W. Sigmund, Amorphous silica nanowires grown by the vapor–solid mechanism, Chem. Phys.

Lett., 376, 498-503 (2003).

[73]Y. Zhang, N. Wang, R. He, J. Liu, X. Zhang, and J. Zhu, A simple method to synthesize Si3N4 and SiO2 nanowires from Si or Si/SiO2 mixture, J. Cryst. Growth, 233, 803-808 (2001).

(5)

[74]L. Dai, X. L. Chen, T. Zhou, and B. Q. Hu, Aligned silica nanofibres, J. Phys. Condens. Matters, 14, L473-L477 (2002).

[75]L. Dai, X. L. Chen, J. K. Jian, W. J. Wang, T. Zhou, and B. Q. Hu, Strong blue photoluminescence from aligned silica nanofibers, Appl. Phys.

Lett., 76, 625-627 (2003).

[76]T. J. Trentler, K. M. Hickman, S. C. Goel, A. M. Viano, P. C. Gibbons, and W. E. Buhro, Solution-liquid-solid growth of crystalline III-V semiconductors: An analogy to vapor-liquid-solid growth, Science 270, 1791-1974 (1995).

[77]X. Lu, T. Hanrath, K. P. Johnston, and B. A. Korgel, Growth of single crystal silicon nanowires in supercritical solution from tethered gold particles on a silicon substrate, Nano Lett., 3, 93-99 (2003).

[78]Y. J. Xing, Z. H. Xi, Z. Q. Xue, and D. P Yu, Diameter modification of Si nanowires via catalyst size, Chin. Phys. Lett., 20, 700-702 (2003).

[79]Y. J. Xing, Z. H. Xi, D. P. Yu, Q. L. Hang, H. F. Yan, S. Q. Feng, and Z. Q. Xue, Growth of silicon nanowires by heating Si substrate, Chin.

Phys. Lett., 19, 240-242 (2002).

[80]S. H. Sun, G. W. Meng, T. Gao, M. G. Zhang, Y. T. Tian, X. S. Peng, Y. X. Jin, and L. D. Zhang, Micrometer-sized Si-Sn-O structures with SiOx nanowires on their surface, Appl. Phys. Lett., 76, 999-1002 (2003).

[81]B. T. Park and K. Yong, Controlled growth of core–shell Si–SiOx and amorphous SiO2 nanowires directly from NiO/Si, Nanotechnology, 15, S365-370 (2004).

[82]K. H. Lee, H. S. Yang, K. H. Baik, J. Bang, R. R. Vanfleet, and W. Sigmund, Direct growth of amorphous silica nanowires by solid state transformation of SiO2 films, Chem. Phys. Lett., 383, 380-384 (2004).

[83]H. Hamamura, H. Itoh, Y. Shimogaki, J. Aoyama, T. Yoshimi, J. Ueda, and H. Komiyama, Structural change of TiN/Ti/SiO2 multilayers by N2 annealing, Thin Solid Films, 320, 31-34 (1998).

[84]M. A. Lieberman, and A. J. Lichtenberg, Principles of Plasma Discharges and Materials Processing, John Wiley & Sons, Inc. (1994).

[85]H. Xiao, Introduction to Semiconductor Manufacturing Technology, Prentice Hall, Inc. (2001).

[86]許博凱著，奈米碳管電漿後處理對場發射特性之影響，大葉大學電機工程學系碩士論文，2007年。

[87]李世鴻著，積體電路製程技術，五南圖書出版公司，1998年。