Table 1. Properties of magnetron-sputtered B4C coatings, together with typical data for three metallic mirror materials.
The properties were determined using Cu radiation (8048 eV) and the coatings deposited onto standard silicon wafer substrates. It should be noted that the surface roughness of a typical silicon substrate used for calibration is similar to that of the later deposited coatings. The layer roughness values were determined by means of X-ray reflectometry and model calculations. Additional roughness values are given in Table 2. ▸
| Coating material | Layer thickness (nm) | Layer density (g cm−3) | Layer roughness (nm) | Critical angle (°) |
|---|---|---|---|---|
| Experimental/theoretical | ||||
| B4C | 58.8 | 2.37 | 0.42 | 0.22/0.22 |
| Mo | 4.8 | 10 | 0.36 | 0.35/0.43 |
| Rh | 45.3 | 12 | 0.39 | 0.47/0.48 |
| Au | 10.7 | 19 | 0.36 | 0.55/0.56 |