Fig. 1. Schematic of the sample structure

Fig. 2. Schematic of laser processing optical path

Fig. 3. Schematics of laser scanning path. （a） Trepanning mode; （b） Filling mode

Fig. 4. Screen picture of online monitoring software operating interface

Fig. 5. Entrance of micro holes processed at different depths. (a) D=1.2 mm; (b) D=1.5 mm; (c) D=1.8 mm; (d) D=2.1 mm; (e) D=2.4 mm; (f) D=2.7 mm

Fig. 6. Exit of micro holes processed at different depths. (a) D=1.2 mm; (b) D=1.5 mm; (c) D=1.8 mm; (d) D=2.1 mm; (e) D=2.4 mm; (f) D=2.7 mm

Fig. 7. Data of penetration forming time at different hole depths

Fig. 8. Relationship between the hole depth and the penetration forming time

Fig. 9. Entrance of micro holes processed at different filling radius. (a) T=2.0 mm, r=150 μm; (b) T=2.0 mm, r=200 μm; (c) T=2.0 mm, r=250 μm; (d) T=2.0 mm, r=300 μm; (e) T=2.5 mm, r=150 μm; (f) T=2.5 mm, r=200 μm; (g) T=2.5 mm, r=250 μm; (h) T=2.5 mm, r=300 μm

Fig. 10. Exit of micro holes processed at different filling radius. (a) T=2.0 mm, r=150 μm; (b) T=2.0 mm, r=200 μm; (c) T=2.0 mm, r=250 μm; (d) T=2.0 mm, r=300 μm; (e) T=2.5 mm, r=150 μm; (f) T=2.5 mm, r=200 μm; (g) T=2.5 mm, r=250 μm; (h) T=2.5 mm, r=300 μm

Fig. 11. Data of penetration forming time at different filling radius

Fig. 12. Relationship between the filling radius and the penetration forming time

Fig. 13. Entrance of micro holes processed at different angles. (a) T=1.0 mm, θ=60.00°; (b) T=1.2 mm, θ=53.13°; (c) T=1.4 mm, θ=45.57°; (d) T=1.5 mm, θ=41.41°; (e) T=1.6 mm, θ=36.87°; (f) T=1.8 mm, θ=25.84°

Fig. 14. Exit of micro holes processed at different angles. (a) T=1.0 mm, θ=60.00°; (b) T=1.2 mm, θ=53.13°; (c) T=1.4 mm, θ=45.57°) ; (d) T=1.5 mm, θ=41.41°; (e) T=1.6 mm, θ=36.87°; (f) T=1.8 mm, θ=25.84°

Fig. 15. Data of penetration forming time at different inclination angle

Fig. 16. Relationship between the inclination angle and the penetration forming time

Fig. 17. Micrography of the hole. (a) Entrance; (b) Exit; (c) Picture of the protective material and the sample with a hole