I've always assumed that "XX nm" doesn't represent the geometry of any particular feature of the end product, but something related to the wavelength of the radiation used for the imaging process.
Maybe it corresponds to the principle emission line of the light source (synchrotron?) In spectral terms, 7 nm is near the border between hard UV radiation and soft X-rays.
Maybe it corresponds to the principle emission line of the light source (synchrotron?) In spectral terms, 7 nm is near the border between hard UV radiation and soft X-rays.