Table 3. Surface Profiles of the Examined Gratings, Diffraction Efficiencies Calculated with Raman–Nath Theory and Associated with Surface Heights, and Experimentally Measured Diffraction Efficiencies in the First Diffraction Ordera.
| period (μm) | height (nm) | theory η0 (%) | theory η1 (%) | experiment η1 (%) |
|---|---|---|---|---|
| 2.1 | 120 | 97.2 | 1.4 | 0.74 ± 0.04 |
| 7.2 | 210 | 91.7 | 4.1 | 3.6 ± 0.6 |
| 7.9 | 400 | 72.4 | 13.2 | 14.4 ± 3.3 |
| 8.0 | 490 | 61.0 | 18.3 | 17.3 ± 1.3 |
| 8.0 | 530 | 55.7 | 20.6 | 18.7 ± 1.6 |
a
Grating periods and heights were determined by AFM measurements.