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The outstanding properties of carbon nanotubes (CNTs) makes them particularly interesting for microelectronic applications such as interconnects and devices. The parallel integration of CNTs using compatible processes is critical for their future application and implies the simultaneous processing of millions of CNTs. In this paper, we present concepts for CNT-based interconnects for large-scale integration. In order to realize this we demonstrate the creation of vertical interconnects (vias) consisting of multi-walled nanotubes and show, for the first time, the growth of single, isolated CNTs at lithographically defined locations. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Many applications of carbon nanotubes (CNTs) require a material with defined properties, however most synthesis routes yield CNTs of varying purity, structure, diameter, and length. Chemical vapor deposition (CVD) allows a good control over the CNTs synthesis and leads to promising results, however the effect of many parameters remains unclear. In order to improve this situation a comprehensive study was carried out under highly controlled conditions. The used CVD reactor was capable to perform deposition processes with temperature deviations smaller than 1°K. The substrates were patterned Fe films with a thickness below 10 nm on silicon/siliconoxide. The effects of the conditioning of the catalyst prior to growth, growth temperature, and growth time were investigated. The synthesis in a hydrogen/acetylene atmosphere yielded pure multi-walled CNTs with diameters between 10-20 nm. The length of the CNTs was accurately controlled by the growth time. The density of the CNTs can be varied by the preconditioning of the catalyst. The controlled synthesis allows an integration of CNTs into technologically relevant structures for microelectronics and elucidates the mechanism of the catalysed CNT growth. [ABSTRACT FROM AUTHOR]

Intermolecular carbon nanotube junctions were formed by coupling chemically functionalized nanotubes with molecular linkers. A T-shape heterojunction can be formed by reacting chloride terminated nanotubes with aliphatic diamine. Electronic devices were prepared by adsorption of functionalized nanotube junctions on Si/SiO[SUB2] substrate followed by standard e-beam lithography. The charge transport through the junction was fund to be strongly modified by the in-plane nanotube mechanically, leading to pronounced metal-insulator transition. [ABSTRACT FROM AUTHOR]

Individual single-wall carbon nanotubes (SWNTs) or thin ropes of SWNTs were characterised in position and size by Scanning Force Microscopy (SFM). Raman spectra of these objects could be obtained and were found to be comprised of well-resolved peaks. The orientation-dependent measurements reveal maximum intensity of all Raman modes when the nanotubes are aligned parallel to the polarisation of the incident laser light. This clearly deviates from the selection rules predicted by theoretical studies and may be explained by depolarisation effects caused by the anisotropic geometry of the nanotubes and by electronic resonance effects. [ABSTRACT FROM AUTHOR]