Vertically aligned multiwalled carbon nanotubes (MWCNTs) were synthesized by remote plasma chemical vapor deposition at a low temperature of 390°C, which meets the requirement of the large scale integration (LSI) process. For wiring application, we measured the electrical properties of MWCNT-via structures with and without chemical mechanical polishing (CMP). The via resistances were reduced using inner shells of MWCNTs whose caps were opened due to CMP. The improved resistance after annealing at 400°C was 0.6Ω for 2μm vias. Our process is suitable for LSI because the temperature never exceeds the allowable temperature of 400°C in the Si LSI process.

The root growth mode of extremely dense and vertically aligned single-walled carbon nanotubes (SWNTs) synthesized by microwave plasma chemical vapor deposition was clarified by a new method, marker growth, which does not require transmission electron microscopy. SWNT layers were grown intermittently on a substrate, and a line between the layers was used as a marker to identify the growth mode. Micro-Raman spectroscopy revealed that the SWNT layers have the same diameter distribution.

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The Raman spectra of vanadium oxides layered on Aerosil have been quantitatively investigated. First, the number of peaks and three parameters of each peak were estimated in a self-generating initial parameter estimation using the B-spline functions. These parameters were refined by a nonlinear optimization technique using the Simplex method. For a series of V2O5/SiO2, three types of vanadium oxide—such as a small cluster vanadate, surface polyvanadate, and crystalline vanadium oxide—were identified and quantitated by Raman spectroscopy. The small cluster surface species is shown to increase with vanadium loadings up to 6.6 wt % V2O5 and to convert into surface polyvanadate species at higher vanadium loadings or heat treatment.