Fig. 1. Schematic diagram of laser dicing system

Fig. 2. Definition of kerf width and ablated zone

Fig. 3. Definition of affected zone width

Fig. 4. Change trend of dicing silicon under pure water. (a) Change trend of kerf width vs speed and frequency; (b) Change trend of ablated zone vs speed and frequency

Fig. 5. Optical image of the grooves on the rear side of silicon

Fig. 6. Surface of silicon diced under water. (a) Silicon surface impacted by bubbles collapse; (b) Enlarged optical image of area B; (c) The first enlarged optical image of area A; (d) The second enlarged optical image of area A

Fig. 7. Bubbles adhering on the surface of the silicon diced in different ethanol-water mixtures with ethanol in water of 0 wt.% (a), 2 wt.% (b), 3.5 wt.% (c), 5 wt.% (d)

Fig. 8. Optical images of front surface diced in different ethanol-water mixtures with ethanol in water of 0 wt.% (a), 2 wt.% (b), 3.5 wt.%(c), 5 wt.% (d)

Fig. 9. Optical images of rear surface diced in different ethanol-water mixtures with ethanol in water of 0 wt.% (a), 2 wt.% (b), 3.5 wt.% (c), 5 wt.% (d)

Fig. 10. Change trend of dicing silicon in ethanol solution. (a) Cut width (characterized by 'Kerf width + affected zone width') of polished surface of silicon vs ethanol concentration; (b) Cut width of non-polished surface of silicon vs vs ethanol concentration

Fig. 11. Morphology of rear surface diced with different ethanol concentrations. (a) 0 wt.%; (b) 2 wt.%

Fig. 12. Optical images of polished-surface of silicon diced with different ethanol concentrations. (a) 0 wt.%; (b) 2 wt.%

Fig. 13. Lateral side view of silicon diced with different ethanol concentrations. (a) 0 wt.%; (b) 2 wt.%; (c) 3.5 wt.%; (d) 5 wt.%

Fig. 14. Change line chart between depth and ethanol concentration

Fig. 15. Dynamics of laser-induced bubble. (a) In deionized water; (b) Under ethanol solution

Fig. 16. Relationship between pulse and bubbles. (a) Under pure water; (b) Under ethanol solution