楊英杰臺灣大學：電機工程學研究所修宇鋒Hsiou, Yu-FengYu-FengHsiou2007-11-262018-07-062007-11-262018-07-062005http://ntur.lib.ntu.edu.tw//handle/246246/53367我們已經成功在已有鐵區塊的Si晶片上使用化學汽相沈積(CVD)方法合成多壁奈米碳管。關於用于運輸特性量測的電極部分是使用標準黃光製程和電子束微影技術來製備。鉻被選擇作為電極材料因為其接觸電阻很小(1kΩ)並且不隨溫度和磁場而變化。在4.2 K.溫度以下，電流電壓(IV)特性顯示非線性的行為這是由Couloumb 堵斷效應。當外加一個垂直磁場時，多壁奈米碳管表現出負磁阻效應及可重複的非週期的擾動。這些特性暗示我們的碳管具有量子干涉的傳輸行為。對一特殊的多壁奈米碳管來說，我們在低於1 K的溫度下觀察到疑似超導行為。We have synthesized multiwalled carbon nanotubes by using thermal chemical vapor deposition (CVD) method on Si chips with pre-patterned iron pads. Standard photolithography and e-beam lithography techniques were exploited to make electrodes for transport measurements. Cr was selected as the electrode material because of the contact resistance is relatively small (~1kΩ) and does not change with temperature and magnetic field. The current-voltage (IV) characteristics generally showed nonlinear behavior at temperatures below 4.2K. This is attributed to the Couloumb blockade tunneling. Upon a perpendicularly applied magnetic field, the tubes showed a negative magnetoresistance with reproducible aperiodic fluctuations. These characteristics were suggestive of quantum interferences. For a particular tube, we observed supercurrent-like IV characteristics at temperatures below 1K.Chapter 1 Introduction 1 Chapter 2 Background 4 2.1 Carbon nanotubes 4 2.2 Electrical properties of carbon nanotubes 7 Chapter 3 Experimental Techniques 14 3.1 Device fabrication 14 3.2 Measurement setup 17 3.3 Scanning electron Microscopy 19 3.4 Transmission electron Microscopy 21 3.5 Atomic force microscopy 23 Capter 4 Growth of carbon naotubes 25 4.1 Carbon nanotubes growth methods 25 4.2 Synthesis of MWNT’s by thermal CVD 31 4.3 Growth factors for synthesis of MWNT’s 34 Chapter 5 Electrical properties of MWNT’s 38 5.1 Contact resistance characterization 38 5.2 Coulomb Blockade 44 5.3 Luttinger Liquid behavior 54 5.4 Magnetotransport 57 5.5 Superconductivity-like behavior 62 Chapter 6 Conclusion and Perspectives 66 References 681887244 bytesapplication/pdfen-US多壁奈米碳管multiwalled carbon nanaotubesthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/53367/1/ntu-94-D87921009-1.pdf