The dependence of the ramp geometry on high- or low-angle ion-beam etching, used to structure ramp-type Josephson junctions based on high- superconductors, is investigated by cross-section transmission electron microscopy. The surface quality, interfaces and crystal defects are analysed by high-resolution electron microscopy. Technical difficulties to reproducibly obtain the desired slope angle and shape make high-angle ion-beam etching less interesting although the surface quality is comparable and no systematic differences in electrical properties are observed.
Verbist, K., Lebedev, O. I., van Tendeloo, G., Verhoeven, M. A. J., Rijnders, A. J. H. M., & Blank, D. H. A. (1996). Low- or high-angle Ar ion-beam etching to create ramp-type Josephson junctions. Superconductor science and technology, 9(11), 978-984. https://doi.org/10.1088/0953-2048/9/11/009