無論就外貌、結構、電性或機械性質，奈米碳管均具有許多優異的特性，因此吸引許多研究奈米相關學者的興趣並投入研究。在本研究中所使用的奈米碳管成長方法為酒精催化化學氣相沈積系統，此方法利用安全的酒精氣體作為碳源，可得到高純度之單壁奈米碳管。
在元件的製程與量測方面，利用簡易的微機電製程製作二極元件之後，即可送入酒精催化化學氣相沈積系統中成長單根懸浮式單壁奈米碳管。成長過程中摻入氣體分子，使用直流量測系統進行量測，而得到傳導特性曲線(I-V curve)。觀察摻入之氣體分子對於單壁奈米碳管導電特性之影響。利用電阻溫度係數(TCR)量測可得知本研究成長出來之碳管屬於金屬或半導體性，進而探討氣體摻雜之成效。
透過實驗數據分析結果顯示，電極微米柱之深寬比以及金屬催化劑溶液濃度是成長單根懸浮式奈米碳管之關鍵因素。微米柱之深寬比必須大於一以上。然而金屬催化劑溶液之濃度為另一重要因素，當濃度小於0.05%時，便無法成功成長出單根懸浮式單壁奈米碳管。當濃度達0.15%時，奈米碳管管徑變粗，此奈米碳管並非本研究所需之單壁奈米碳管。因此最佳濃度介於0.05~0.15%之間。
最後，電極與奈米碳管間沒有若好的連接，導致電極與奈米碳管間之接觸電阻非常大，將對往後之應用造成決定性影響。

Carbon nanotubes have attracted many attentions and interests of the researchers due to their excellent appearance, structure, electricity or mechanical properties. Single-walled carbon nanotubes (SWNTs) were prepared with alcohol catalytic chemical vapor deposition (ACCVD). Safe alcohol vapor is used as a carbon source for growing pure SWNTs.
The nanotube devices was fabricated by the process of microelectromechanical system (MEMS). The individual single-walled nanotube devices was doped by introducing the nitrogen to ACCVD reactor. In this article, standard semiconductor parameter extraction systems were used for the measurement of transfer characteristics of nanotube devices. The temperature coefficient of resistance (TCR) could help us to know the characteristics of the nanotubes. We could observe the doping effect of the nanotube devices.
Show through the analysis result of the experimental data, there were finded that the height of electrode micro-pillars and the concentration of catalysts play very important roles in growing individual suspended SWNTs. The distance from the top of the pillars to the bottom of them must be longer than the distance between the opposite pillars. Furthermore, when the concentration of the catalysts was lower than 0.05%, it was failure for growing individual suspended SWNTs. However, when the concentration was 0.15%, the diameter of SWNTs became bigger. They are not SWNTs. So the concentration of the catalysts must be between 0.05%~0.15%.
Finally, high contact resistances may be due to the loose contacts between nanotubes and electrodes. It will affect the application of the individual suspended SWNT.

參考文獻
[1] H. W. Kroto, J. R. Heath, S. C. O'Brien, “C60: Buckminsterfullerene”, Nature, 318, p.162-163.(1985)
[2] S. Iijima, “Helical microtubules of graphitic carbon,” Nature, 354, p.56–589.(1991)
[3] N. Hamada, Sl. Sawada, and A. Oshiyama, “New one–dimensional conductors: graphitic microtules,” Phys.Rev.Lett,68, P.1579–1581.(1992)
[4] J. W. Mintmire, B. I. Dunlap, andC. T. White, “Are fullerene tubules metallic,” Phys. Rev. Lett, 68 ,p.631-634.(1992)
[5] L. M. Peng, Z. L. Zhang, Z. Q. Xue, Q. D. Wu, Z. N. Gu, andD. G. Pettifor, “Stability of carbon nanotubes：How small can they be?,” Phys. Rev. Lett, 85, p.3249-3252.(1992)
[6] M. S. Dresselhaus, G. Dresselhaus, R. Saito, “Physics of carbon nanotubes,” Carbon, 33, p.883-891.(1995)
[7] M. Jose-Yacaman, M. Miki-yoshida, L. Rendon, “Catalytic growth of carbon microtubules with fullerene structure,” Appl Phys Lett, 62, 2029.(1993)
[8] H. Jaeger, T. Behrsing, “Dual nature of vapour-grown carbon fibres,” Composite Sci Tech, 51, 231.(1994)
[9] M. Jose-Yacaman, H. Terrones, L. Rendon, Carbon, “Carbon structures grown from decomposition of a phenylacetylene and thiophene mixture on Ni nanoparticles,” Carbon, 33, 669.(1995)
[10] N. M. Rodriguez, M. S. Kim, R.T. K. Baker. “ Carbon nanofibers. A unique catalyst support medium ,” J. Phys. Chem, 98, 13108.(1994)
[11] 朱宏偉，慈立傑，梁吉等. “新型碳材料,” 15, p.48.(2000)
[12] H. M. Cheng, F. Li, G. Su, “Large-scale and low-cost synthesis of single-walled carbon nanotubes by the catalytic pyrolysis of hydrocarbons,” Appl Phys Lett, 72, 3282.(1998)
[13] T. W. Ebbesen, and P. M. Ajayan, “Large-scale synthesis of carbon nanotubes,” Nature ,358 , p.220-222.(1992)
[14] S. Iijima, T. Ichihashi, “Single-shell carbon nanotubes of 1-nm diameter,” Nature, 363, p.603-605.(1992)
[15] Y. Saito, M. Okuda, M. Tomita and T. Havashi, “Extrusion of. single-wall carbon nanotubes via formation of small particles condensed near an arc evaporation source,” Chem. Phys.Lett, 236, (1995)419.
[16] A. Thess, R. Lee, P. Nikolaev, H. Dai, P. Petit, J. Robert, C. Xu, Y. H. Lee, S. G. Kim, A. G. Rinzler, D. T. Colbert, G.Scuseria,D Tomnek, J. E. Fischeo,and R. E. Smalley, “Crystalline ropes of metallic carbon nanotubes,” Science, 273 , p.483-487.(1996)
[17] S. Zhu, C. H. Su, J. C. Cochrane, S. Lehoczky, Y. Cui ,and A. Burger, “Growth oriention of carbon nanotubes by thermal chemical vapor 　deposition,” Journal of Crystal Growth, 234 p.584-588.(2002)
[18] X. Wang, Z. Hu, Q. Wu, X. Chen, and Y. Chen, “Synthesis of multi-walled carbon nanotubes by microwave plasma-enhanced chemical vapor deposition,” Thin Solid Films, 390 ,p.130-133.(2002)
[19] Y. C. Choi, Y. M. Shin, Y. H. Lee,and B. S. Lee, “Controlling the diameter,growth rate,and density of vertically aligned carbon nanotubes synthesized by microwave plasma-enhanced chemical vapor deposition,” Appl Phys Lett , 76 , p.2367-2369.(2000)
[20] T. Komukai, K. Aoki, H. Furuta, M. Furuta, K. Oura, T. Hirao, “Density control of carbon nanotubes through the thickness of Fe/ Al multilayer catalyst,” Jpn. J. Appl Phys ,45, p. 6043–6045.(2006)
[21] M. Chhowalla, K. B. K. Teo, C. Ducati, N. L. Rupesinghe, G. A. J.Amaratunga, A. C. Ferrari, D. Roy, J. Robertson and W. I. Milne, “Growth process conditions of vertically aligned carbon nanotubes using plasma enhanced chemical vapor deposition,” J. Appl. Phys, 90, p.5308.(2001)

[22] S. Honda, Y. G. Baek, K. Y. Lee, T. Ikuno, T. Kuzuoka, J. T. Ryu, S.Ohkura, M. Katayama, K. Aoki, T. Hirao and K. Oura, “Synthesis of randomly oriented carbon nanotubes on SiO2 substrates by thermal chemical vapor deposition toward field electron emitters,” Thin Solid Films , 464–465 , p.290.(2004)
[23] T. Ikuno, S. Honda, H. Furuta, K. Aoki, T. Hirao, K. Oura and M. Katayama, “Correlation between field electron emission and structural properties in randomly and vertically oriented carbon nanotube films,” Jpn. J. Appl. Phys,44 , p.1655.(2005)
[24] O. Smiljanic, T. Dellero, A. Serventi, G. Lebrun, B. L. Stansfield, J. P. Dodelet, M. Trudeau and S. Désilets, “Growth of carbon nanotubes on Ohmically heated carbon paper,” Chem. Phys. Lett,342, p.503-509.(2001)
[25] Y. H. Wang, J. Lin, C. H. A. Huan and G. S. Chen , “Synthesis of large area aligned carbon nanotube arrays from C2H2–H2 mixture by rf plasma-enhanced chemical vapor deposition,” Appl. Phys. Lett,79 p.680.(2001)
[26] H. Sato, K. Hata, and K. Hiasa, “Low temperature growth of carbon nanotubes by alcohol catalyticchemical vapor deposition for field emitter applications, ” J. Vac. Sci. Technol, 25, p.579.(2007)
[27] T. M. Wu ,Y. W. Lin, “Doped polyaniline/multi-walled carbon nanotube composites: Preparation, characterization and properties,” Polymer, 47, p.3576–3582.(2006)
[28] T. Matsumoto, Y. Homma, Y. Kobayashi, “Bridging Growth of Single-Walled Carbon Nanotubes on Nanostructures by Low-Pressure Hot-Filament Chemical Vapor Deposition,” J. Appl. Phys, 44 (2005)7709.
[29] A. Cassell, N. Franklin, E. Chan, J. Han, H. Dai. “Directed Growth of Free-Standing Single-Walled Carbon Nanotubes,” J. Am. Chem. Soc, 121, 7975-7976, 1999.
[30] N. Franklin, H. Dai. “An Enhance Chemical Vapor Deposition Method to Extensive Single-walled Nanotube Networks with Directionality,” (featured in cover) Advanced Materials, 12, 890, 2000.
[31] T. L. Li, J. H. Ting, B. Z. Yang, “Conducting properties of suspended carbon nanotubes grown by thermal chemical vapor deposition,” 1221 J. Vac. Sci. Technol. B , 25(4), Jul/Aug 2007
[32] Y. Zhao , T. Sugai , H. Shinohara , Y. Saito, “Controlling growth and Raman spectra of individual suspended single-walled carbon nanotubes,” Journal of Physics and Chemistry of Solids, 68 (2007) 284–289.
[33] Ph. Buffat, J.P. Borel, “Size effect on the melting temperature of gold particles,” Phys. Rev. A, 13 (1976) 2287.
[34] N. Franklin, Q. Wang, T. Tombler, A. Javey, H. Dai. “Integration of Suspended Carbon Nanotube Arrays Into Electronic Devices and Electromechanical Systems,” Appl. Phys. Lett, 81(5), 913, 2002.
[35] G. Zhang, D. Mann, L. Zhang, A. Javey, Y. Li, E. Yenilmez, Q. Wang, J. McVitti, Y. Nishi, J. Gibbons, H. Dai, “Ultra-High-Yield Growth of Vertical Single-Walled Carbon nanotubes: Hidden Roles of Hydrogen and Oxygen,” PNAS, 102, 16141, 2005.
[36] M. Sveningsson, R. E. Morjan, O. A. Nerushev, Y. Sato, J. Backstrom, E. E. B. Campbell, and F. Rohmund, Appl. Phys. A: Mater. Sci. Process, 73,409 (2001)
[37] J. H. Ting, T. L. Li, Y. C. Hong, “Dependence of field emission properties of carbon nanotube films on their graphitization,” Journal of Vacuum Science and Technology B, Vol. 24 No. 4, Jul/Aug 2006, pp. 1794-1798.
[38] H. Son, et. al., “Environmental effects on the Raman Spectra of Individual Single Wall Carbon nanotubes: Suspended and Grown on Polysilicon,” Appl. Phys. Lett, 85 , 4744 (2004)
[39] D. Kang, N. Park, J. H. Ko, E. Bae and W. Park, “Oxygen-induced p-type doping of a longindividual single-walled carbon nanotube,” INSTITUTE OF PHYSICS PUBLISHING Nanotechnology, 16 (2005) 1048–1052

[40] A. Javey, M. Shim, and H. Dai, “Electrical properties and devices of large-diameter single-walled carbon nanotubes,” Appl. Phys. Lett, 80, 1064 (2002).
[41] M. H. Yang, K. B. K. Teo, W. I. Milne, and D. G. Hasko, “Carbon nanotube Schottky diode and directionally dependent field-effect transistor using asymmetrical contacts,” Appl. Phys.Lett, 87, 253116 (2005).
[42] H. M. Manohara, E. W. Wong, E. Schlecht, B. D. Hunt, and P. H. Siegel, “ Carbon Nanotube Schottky Diodes Using Ti−Schottky and Pt−Ohmic Contacts for High Frequency Applications,” Nano Lett, 5, 1469 (2005).
[43] T. Helbling , R. Pohle , L. Durrer , C. Stampfer , C. Roman,A. Jungen , M. Fleischer , C. Hierold , “ Sensing NO2 with individual suspended single-walled carbon nanotubes,” Sensors and Actuators B , xxx (2008) xxx–xxx
[44] J. Kong, N.R. Franklin, C.W. Zhou, M.G. Chapline, S. Peng, K.J. Cho, H.J.Dai, “Nanotube molecular wires as chemical sensors,” Science, 287 (5453)(2000) 622–625.
[45] S. Peng, K.J. Cho, P.F. Qi, H.J. Dai, “Ab initio study of cnt NO2gas sensor,Chem,” Phys. Lett, 387 (4–6) (2004) 271–276.
[46] J. Zhang, A. Boyd, A. Tselev, M. Paranjape, P. Barbara, “Mechanism of NO2 detection in carbon nanotube field effect transistor chemical sensors,” Appl. Phys. Lett, 88 (12) (2006) 3.
[47] R. Martel, T. Schmidt, H. R. Shea, T. Hertel, and Ph. Avouris, “Single- and multi-wall carbon nanotube field effect transistors,” Appl. Phy. Lett., vol. 73, pp. 2447-2449, 1998.
[48] L. A. W. Robinson,et al., “Fabrication of self-aligned side gates to carbon nanotubes,” NANOTECHNOLOGY, 14, pp. 290-293, 2003
[49] S. J. Wind, et al., “Vertical scaling of carbon nanotube field effect transistors using top gate electrodes,” Appl. Phy. Lett, vol. 80 no. 20, 2002.
[50] S. Maruyama, R. Kojima, Y. Miyauchi, S. Chiashi, M. Kohno,“Low-temperature synthesis of high-purity single-walled carbon nanotubes from alcohol,” Chemical Physics Letters, 360, p.229–234.(2002)
[51] Y. Murakami, Y. Miyauchi, S.Chiashi, S. Maruyama, “Direct synthesis of high-quality single-walled carbon nanotubes on silicon and quartz substrates,” Chemical Physics Letters, 377, p.49–54.(2003)
[52] Y. Murakami, Y. Miyauchi, S. Chiashi, S. Maruyama, “Characterization of single-walled carbon nanotubes catalytically synthesized from alcohol,” Chemical Physics Letters,374, p.53–58.(2003)
[53] Y. Murakami , S. Chiashi , Y. Miyauchi , M. Hu ,M. Ogura , T. Okubo, S. Maruyama, “Growth of vertically aligned single-walled carbon nanotube films on quartz substrates and their optical anisotropy,” Chemical Physics Letters, 385, p.298–303.(2004)
[54] A. Jorio, A. G. Souza Filho, G. Dresselhaus, M. S. Dresselhaus, A. K. Swan, M. S. Unlu, B. B. Goldberg, M. A. Pimenta, J. H. Hafner, C. M. Lieber, and R. Saito,“G-band resonant Raman study of 62 isolated single-wall carbonnanotubes,” Physical Review B, 65, 155412(2002).
[55] Y. S. Han, J. K. Shin, and S. T. Kim, “Synthesis of carbon nanotube bridges on patterned silicon wafers by selective lateral growth,” J. Appl. Phys, 90, 5731 (2001).
[56] V. Derycke,; R. Martel,; J. Appenzeller; Avouris, Ph. Appl. Phys.Lett, 2002, 80, 2773-2775.
[57] S. Heinze, J. Tersoff, R. Martel, V. Derycke , J. Appenzeller, and Avouris, Ph (2002) “Carbon nanotubes as Schottky barrier transistors ,” Phys. Rev. Lett, 89 , p. 106801.
[58]K. S. Kim, D. J. Bae, J. R. Kim, K. A. Park, S. C. Lim, J. J. Kim, W. B. Choi, C. Y. Park, and Y. H. Lee, “Modification of Electronic Structures of a Carbon Nanotubes by Hydrogen Functionalization,” adv. Mater, 2002, 14, No. 24

[59]E. Ech-chamikh, A. Essafti, Y. Ijdiyaou, M. Azizan, “XPS study of amorphous carbon nitride (a-C:N) thin films deposited by reactive RF sputtering,” Solar Energy Material & Solar Cell,90 (2006) 1420-1423