We have recently realized the two-dimensional visualization of a oligoethyleneglycol (OEG)/mannose (Man)-terminated pattern surface by performing AFM force measurements using a concanavalin A (ConA)-modified AFM tip. To extend the visualization technique, various types of patterned surfaces with localized sugar chains were fabricated by lithography and their two-dimensional visualizations were challenged in a phosphate-buffered saline solution by AFM force measurements using a ConA-modified AFM tip in this study. The adhesion force based on the interaction of ConA with Man was much larger than that based on the interaction of ConA with phosphorylcholine or galactose. The spatial resolution of this method was evaluated using a nanopatterned surface fabricated using silica nanoparticles. Man-terminated regions were clearly distinguishable from OEG-terminated regions on a nanometer scale.

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Application of an inclined holder based on geometric properties of the Auger electron spectroscopy (AES) apparatus equipped with a concentric hemispherical analyzer to AES sputter depth profiling improves the flexibility in setting of the incidence angles of both electrons and ions. In particular, when the incidence direction of the electron beam coincides with the axis of the specimen azimuthal rotation, the incidence angle of ions can be obliquely determined by the rotation angle of the inclined holder and the incidence angle of the electron beam can be set independently by choosing the inclination angle of the inclined holder. Basing on this concept, we developed a 85°-high-angle inclined specimen holder which enabled the specimen surface to be irradiated by both the electron and ion beams at the glancing incidence. We have investigated the high-depth resolution AES sputter depth profiling analysis with the inclined specimen holder. In consequence, the resultant depth resolution for the GaAs/AlAs superlattice was found to be independent of the sputtered depth and the highest depth resolution of 1.7 nm was achieved with the Al-LVV Auger peak. The Auger depth profiles of the Si/Ge multiple delta-doped layers revealed that the Ge mono-layer can be in-depth profiled with high sensitivity and high depth resolution using the inclined specimen holder. In this article, we outline the basic comcept of the high-sensitivity and high-depth resolution AES sputter depth profiling using the inclined specimen holder and its application to the AES depth profiling.

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A reflection high-energy positron diffraction apparatus consists of several elements such as a positron source, a beam moderator, a beam accelerator, a monochromator, lenses, a specimen holder and an observation system. Here, features of these elements are explained and quality of positron beams required for diffraction experiments, such as parallel quality and coherence length of positron beams, is described.

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