In order to evaluate the nanometer-scale work function (Apparent Local Barrier Height: LBH) relating to physical and chemical characteristics of the surface by means of the scanning tunneling microscope, we have examined the relation between measurement condition (in this case, the tip-sample bias voltage) and obtained LBH. It is found that there is correlation of the bias voltage effect on LBH with the current-voltage (I-V) characteristic. Therefore, if the LBH is scanned, the I-V curve have to be measured at the same tip-sample separation used in the scan, in order to classify the bias voltage used in the scan.

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We have carried out a round robin test for the evaluation of sample damage of polyvinyl chloride (PVC) and nitrocellulose and cellulose acetate (NC-CA) due to monochromatic X-ray irradiation, and obtained the following results. It is possible to evaluate the sample surface damage from the degradation rate constants of PVC and NC-CA sample if we use the special holder developed in this research. This hoder has a hole on substrate to prevent the diffusion of the heat and also has a thin metal plate cover to keep the sample surface flat. The resulting ratio of the degradation rate constant of PVA to that of NC-CA is a universal constant (0.174 ±0.015), which is independent from used XPS instrument. Then, PVC and NC-CA will be good specimens for the indicator of X-ray source flux

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Experimental C1s core-electron binding energy (CEBE) of hydrocarbons, alcohols or organic acids, which contain C_nH_2n+1-functional group, on MgO is determined as 286.5 eV. The value is larger than 285.0 eV as the standard value relative to the C1s CEBE of polyethylene. We discuss the physisorption type of CH₄ on the MgO clusters from theoretical viewpoints of both ab initio molecular orbital (MO) and density-functional theory (DFT) calculations. We try to indicate whether the organic molecules physisorb on MgO, or not, using accurate computational results of CEBE by the DFT calculation.

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In depth profiling measurements with AES, XPS, and SIMS, the sputter etching rate is one of the important parameters. We have proposed the mesh-replica method (J. Surf. Anal. 5, 188 (1999) ) to measure the actual sputtered depth even for a wide sputtered area. SERD (Sputter etching rate database)project in SASJ has been developing the relative sputter etching rate database using this technique. In this report, we show the sputter etching rate ratios of Si to SiO₂ by collaborating study, and they were determined to be 1.04±0.10 and 1.02±0.07 for the Ar⁺ ion beam energies of 1 keV and 3 keV, respectively. From the results, it was found that the sputter etching rates of Si were almost the same as those of SiO₂.

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In order to perform a quantitative analysis by electron spectroscopy, precise information on the transmission function of the spectrometer is crucial for comparison of spectra obtained with different analytical conditions or by different models of spectrometers. A preliminary round robin test for comparison of transmission functions of different models of XPS spectrometers was conducted by some members of SASJ, and it was shown that standardization of the transmission correction procedure is necessary to perform quantitative analysis with relatively small uncertainty.

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