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Scanning electron microscopes (SEMs) are widely used as an observation instrument for microsurface topology, and for critical dimension measurements in the semiconductor factories. We have developed a metrological SEMs and silicon standard reference artifacts. While the electron beam is fixed at a point, the specimen is scanned mechanically as the interferometer measures an interval between two positions (a starting and an ending point) precisely. The used laser is traceable for a wavelength standard. The instrument with a resolution of 0.8 nm was developed first. However it is not realistic nor feasible for users because of its unique specification and construction. We attempt the spread of metrological devices with an absolute scale, which realized by a compact laser interferometer capable of installing in regular SEMs. We have developed the compact interferometer in collaboration with Nikon. The compact interferometer with combined with a piezo driven mechanical scanner, is integrated in a stainless-steel disk of 130 mm diameter. The resolution of 0.4 nm is obtained. We also tried to fabricate the test artifact with the linewidth of sub-m. Standard microscales (pitch; 0.24m}0.001m) have been fabricated by Hitachi, and cross-checked and sold with a certificate of calibration attached by JQA (Japan Quality Assurance Organization). We were awarded three prizes for three technical papers.
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