| Owing to their unique nanoscale one-dimensional structures and remarkable mechanical, electrical, thermal, optical and biological properties, carbon nanotubes (CNTs) are promising candidates for use in a new generation of nanoelectronic device fabrication. Although different assembly methods and functions of the CNTs in actual applications, their basic structure is interconnect structures of the CNTs and metal electrodes. During the fabrication of the CNT based device, the common problem faced is achieving improved contacts between the CNTs and metal electrodes, so as to obtain a reliable mechanical connection and efficient energy transfer mechanism at the contact interface. However, the exising studies were focused on the energy transfer mechanism of the ideal contact interface, while studies on the contact configuration evolution is still lacking. In addition, the process of how to achieve the interfacial bonding between the CNT and metal structure is worthy of further study.We carried out molecular dynamics simulation to investigate the physical mechanism of the interfacial bonding between the CNT and metal,from which we analyzed the factors that affect the interfacial bonding and propose an effective process technology to realize bonding of the CNT onto the micron electrode. Finally, combining applications of carbon nanotubes in electronic packaging, bonding and transfer of vertically aligned carbon nanotube arrays were achieved. The significant results achieved in this dissertation are given below:First, we carried out modeling of the interfacial bonding of CNTe/metal interconnect structure. The molecular dynamics simulation results show that the physical mechanisms of the interfacial bonding includes surface melting of the metal and the wetting of the metal atoms on the CNT surface. During the bonding, a side contact structure and core filling nanowires form at the carbon nanotube-metal interface. It is found that the bonding could be accomplished at a temperature much lower than the melting point of the metal due to the surface melting behavior. In addition, the wetting of the metal atoms on the CNT surface is determined by the competition between metal-metal and metal-CNT interaction. Also, the atomistic study indicates that the surface charges can improve the wetting properties between metal atoms and the carbon nanotube surface. These behaviors provide more choices of metallic electrodes rather than using metals with excellent wetting properties to the carbon nanotube.Next, according to simulation results, the high frequency induction heating method is used to realize bonding of the CNTs onto the metal electrode. This method provides surface charges which would facilitate the interfacial bonding. Furthermore, this non-contact and selective heating allows us to bond CNTs onto electrodes in large-scale without heating the whole structures. The contact resistance can be reduced by approximate 96%, and the reduction is irreversible.Finally, a nano-interface thermocompression bonding method is used to achieve bonding of vertical aligned CNTs onto the metallic substrate. The results show that formation of metal cluster on the end of the CNT by metal deposition provides a nanoscale metal surface to facilitate diffusion bonding. And then the bonding of vertical aligned CNTs onto the metallic substrate can be achieved under a certain temperature and pressure conditions. The debonding process indicates that the bonding strength is larger enough so that the fracture occurs on the CNTs themselves. The measurements of the electrical properties of the CNT/metal interconnect structure show that an ohmic contact is formed between the CNTs and the metal. The resistivity is 9 x10-7?m. These characteristics indicate that the transterred CNT arrays may be a good alternative to metal interconnects in microelectronic packaging. The meaningful results obtained in this study revealed the mechanism of CNT/metal interfacial bonding process, and some effective methods are proposed to achieve interfacial bonding of CNT/ metal interconnect structure, which lay the foundation for fabrication of CNT based device and nanopackaging.
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