Table 1.
Set of parameters used in the present work and in several references where regular LIPSS were obtained.
| Materials | Wavelength λ (nm) | Pulse duration τ (fs) | Energy per pulse E (nJ) | F * [J/cm 2] (F abs † [J/cm2]) | Repetition rate f (kHz) | Scanning velocity v | Spot diameter σ at 1/e2 (μm) | Effective pulse number# | Overlapping§ (%) | Throughput (109 μm 2/h) | DLOA δθ | LIPSS period Λ (nm) | Reference |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cr | 1030 | 500 | 1950 | 0.039 (0.017) | 250 | 1.5 m/s | 80 | 13.3 | 92.5 | 9 | 13.0° ± 1.0° | 913 ± 53 | Ref. 15. |
| Mo | 1030 | 213 | 583 | 0.69 (0.228) | 600 | 1.7 m/s | 10.4 | 3.67 | 72.8 | 21 | 5.3° ± 0.5° | 845 ± 38 | This work |
| 800 | 50 | — | 0.07 (0.031) | 1 | 0.04 mm/s | ~30 | ~750 | 99.9 | 0.0058 | 8.3° ± 0.5° | 589 ± 30 | Ref. 24. | |
| Ti | 1030 | 213 | 500 | 0.59 (0.228) | 600 | 3 m/s | 10.4 | 2.08 | 51.9 | 38 | 9.2° ± 0.5° | 737 ± 26 | This work |
| 800 | 30 | — | 0.033 (0.013) | 1 | 0.6 mm/s | 22 | 37 | 97.2 | <0.05 | 8.5° ± 0.5° | ~660 | Ref. 25. | |
| Steel | 1030 | 213 | 383 | 0.45 (0.159) | 600 | 3 m/s | 10.4 | 2.08 | 51.9 | 38 | 9.2° ± 0.5° | 901 ± 38 | This work |
| 790 | 30 | — | 0.055 — | 1 | 5 mm/s | 280 | 56 | 98.2 | <5.1 | 15.0° ± 1.0° | 600 ± 80 | Ref. 9 | |
| Ni | 1026 | 232 | 130 | 0.46 (0.129) | 1 | 0.5 mm/s | 6 | 12 | 91.7 | — | 20.0° ± 0.8° | 760 ± 120 | Ref. 26. |
| 800 | 90 | — | 0.16 (0.051) | 1 | 2.0 mm/s | 40 | 20 | 95.0 | — | 14.6° ± 0.5° | ~650 | Ref. 27. | |
| Al | 1030 | 213 | 917 | 1.08 (0.053) | 600 | 3 m/s | 10.4 | 2.08 | 51.9 | — | 26.7° ± 0.5° | 842 ± 134 | This work |
| Cu | 1030 | 213 | 1500 | 1.77 (0.070) | 600 | 3 m/s | 10.4 | 2.08 | 51.9 | — | 23.8° ± 0.5° | 956 ± 85 | This work |
| Au | 1030 | 213 | 4080 | 4.80 (0.101) | 600 | 3 m/s | 10.4 | 2.08 | 51.9 | — | 48.8° ± 1.0° | 893 ± 160 | This work |
Throughputs and DLOAs for highly regular LIPSS (HR-LIPSS) fabricated in this work are highlighted by bold typesetting. * F is the average fluence of individual laser pulses and was estimated by the expression F = 4E/(πσ 2), where σ is the spot diameter at 1/e2 of peak intensity. †The absorbed fluence, F abs = (1 − R)F, was obtained using the room temperature reflection coefficient R from Johnson et al.28 for Ti and Cr, from Ordal et al.29 for Mo, from Palik30 for Ni, Al, Cu and Au. For steel, effective medium theory is used (see also Table 2). However, it must be emphasized that depending on metals, the optical properties can significantly vary during the irradiation, leading to a drop in the reflectivity and an increased absorbed fluence31. #The pulse number is N = fσ/v where f is the repetition rate of the laser and v is the scanning velocity. §The overlap is estimated as (1 − 1/N) × 100%.