Since the discovery of carbon nanotubes (CNT) in 1999, they have attracted much attention due to their unique mechanical and electrical properties and potential applications. Yet their nanosize makes the study of individual CNTs easier said than done. In our laboratory, carbon fibers with nanotube cores have been synthesized with conventional chemical vapor deposition (CVD) method. The single multiwall carbon nanotube (MWNT) sticks out as a tip of the carbon fiber. In order to pick up the individual CNT tips, focused ion beam (FIB) technique is applied to cut and adhere the samples. The carbon fiber with nanotube tip was first adhered on a micro-manipulator with the FIB welding function. Afterwards, by applying the FIB milling function, the fiber was cut from the base. This enables us to handle the individual CNT tips conveniently. By the same method, we can attach the nanotube tip on any geometry of solid samples such as conventional atomic force microscopy (AFM) silicon tips. The procedures developed for the FIB assisted individual CNT tip fabrication will be described in detail. Because of their excellent electrical and stable chemical properties, individual CNTs are potential candidates as electron guns for electron based microscopes to produce highly coherent electron beams. Due to the flexibility of the FIB fabrication, the individual CNT tips can be easily fabricated on a sharpened clean tungsten wire for field emission (FE) experimentation. Another promising application for individual CNT tips is as AFM probes. The high aspect ratio and mechanical resilience make individual CNTs ideal for scanning probe microscopy (SPM) tips. Atomic force microscopy with nanotube tips allows us to image relatively deep features of the sample surface at near nanometer resolution. Characterization of AFM with individual CNT tips and field emission properties of single CNT emitters will be studied and presented.
| Identifer | oai:union.ndltd.org:ucf.edu/oai:stars.library.ucf.edu:etd-1167 |
| Date | 01 January 2004 |
| Creators | Chai, Guangyu |
| Publisher | STARS |
| Source Sets | University of Central Florida |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | Electronic Theses and Dissertations |
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