We have performed electroabsorption spectroscopy on micelle-wrapped single-wall carbon nanotubes. In semiconducting nanotubes, many oscillating structures composed of the increase and decrease of absorption are observed in the spectra in the region of the first and second absorption bands, E11 and E22. The spectral shape is reproduced mainly by the second-derivative curve of the absorption spectrum, which indicates the presence of nearly degenerate bright and dark excitonic states.

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In Auger electron spectroscopy, the relative sensitivities of elements, which are widely used in quantitative analysis, are primarily obtained by measurement. Nevertheless, it is very tedious to collect all relative elemental sensitivity factors for different primary electron beam energies. In view of this, we have examined methods of deriving the relative sensitivity factor for an arbitrary electron beam energy from one experimental value determined at a set energy. For this calculation, we have to consider the contributions of the ionization cross-section and the electron backscattering factor. Several formulas for the ionization cross-section and the backscattering correction factor have been reported. We have performed experiments to examine their correction accuracy. It was found that when Gryzinski's formula is used as the ionization cross-section and Love-Scott's formula as the backscattering correction factor, the difference between calculated sensitivity values and measured values was found to be < 15% for excitation energies of < 20 keV.

In order to analyse polymers by AES, the electron discharge from the sample surface and the reduction of electron irradiation damage must be taken into account. A cooling device for a scanning Auger microprobe was developed that allows five axis movements, especially allowing a large dynamic range of tilt movement. The electron beam irradiation effects were examined for C1 LVV and C KLL transitions at temperatures of -185, -150, -100 and 24 "C using slices of polyvinyl chloride specimen of -200 nm in thickness. At -185 "C, the allowed dosage for the analysis without causing any remarkable damage is up to 0.3 C cm-*. The electron dosage effects are not so strong. The logarithmic concentration ratio log(Cc,/Cc) falls down linearly against the logarithmic electron dosage log(electron dose) with a slope of about -0.22. At higher temperatures the damage take place immediately after electron irradiation, and it cannot be avoided. This immediate damage is not due to the dosage effects but to the temperature elevation.

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