Surface analysis methods are widely used during the fabrication process of advanced devices. For practical applications in advanced industries, surface analysis methods should be standardized by the establishment of traceability and with the development of measurement procedures and certified reference materials. Measurement traceability for surface analysis is established by key comparisons (KCs) by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). Thus far, two KCs for thickness measurements of nm SiO₂ films (K-32) and for analyses of the atomic fractions of Fe-Ni alloy films (K-67) have been performed. International standards for surface chemical analysis procedures have been developed by ISO/TC-201. Fifty nine international standards have been published. The Korea Research Institute of Standards and Science (KRISS) has participated in key comparisons of the CCQM SAWG as the national metrology institute (NMI) of Korea. KRISS has also participated in ISO/TC-201 to develop international standards for surface analysis using XPS, AES and SIMS. Three types of thin-film certified reference materials have been developed by KRISS.

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The electronic structure of a Ta₂O₅ thin film on SiO₂/Si (100) after Ar Gas Cluster Ion Beam (GCIB) sputtering was investigated using X-ray photoemission spectroscopy and compared with those obtained via mono-atomic Ar ion beam sputtering. The Ar ion sputtering had a great deal of influence on the electronic structure of the oxide thin film. Ar GCIB sputtering without sample rotation also affected the electronic structure of the oxide thin film. However, Ar GCIB sputtering during sample rotation did not exhibit any significant transition of the electronic structure of the Ta₂O₅ thin films. Ar GCIB can be useful for potential applications of oxide materials with sample rotation.

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The surface of BaTiO₃ single crystal was cleaned by Ar gas cluster ion beam (Ar-GCIB) etching. We carried out XPS measurement on the cleaned surface and clarified chemical state’s changes of Ti and Ba element. Surface cleaning was also carried out by the conventional Ar monoatomic ion beam etching to compare the damage on the chemical state of BaTiO₃ single crystal. Ti was reduced and changed its valence from Ti⁴⁺ to Ti³⁺ by Ar monoatomic ion beam etching at 2 keV energy. Moreover, Ba 3d XPS spectrum showed a large peak shift of 2 eV toward higher binding energy. On the other hand, we found that Ar-GCIB is useful to clean the surface without any chemical state’s change of Ti and Ba in BaTiO₃ single crystal.

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Auger electron spectroscopy (AES) is frequently applied for sputter depth profiling of ultra thin films. The angle of incidence of sputter ion is selected depending on the purpose of the depth profiling. The depth resolution is improved by applying glancing angle of ion beam. An inclined holder and adequate rotation angle of stage is proposed in order to implement the glancing angle of ion beam. However, the experiment requites delicate conditions. In this study, effect of angle of incidence of ions caused by inaccuracy of stage tilt angle and stage rotation angle was investigated using computer calculation. The numerical results for some commercial AES equipment are also reported.

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