According to the new mise en pratique, the lattice spacing of silicon can be used as a secondary realization of the meter in nanometrology. To this end, a reliable and robust workflow has been established using transmission electron microscopy (TEM). Cross-sectional specimens of Si of various thicknesses were successfully prepared using a focused ion beam (FIB). The {220} lattice spacings of Si were measured by double aberration corrected TEM with a spatial resolution of 60 pm. Thereby, unavoidable drifts were effectively minimized. Finally, the standard deviation of the measured {220} d-spacings of Si reached 1 pm.
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