Surface machinability enhancement of 4H–SiC wafer by ultrafast laser: Phase transformation and microstructural evolution
Source abstract
Abstract
To address the poor surface machinability of hard and brittle single-crystal SiC caused by its high hardness, brittleness, and strong chemical inertness, femtosecond laser surface modification offers an effective approach to enhance machinability. However, limited understanding of surface phase transformation and reconstruction hinders precise process control. In this study, combined finite element method ( FEM ), reactive force field molecular dynamics ( ReaxFF MD ), and experiments were employed to reveal the mechanisms of femtosecond laser-induced surface phase transformation and reconstruction. The modification threshold of SiC under single-pulse irradiation was determined to be 1.91 J/cm 2 , with a critical free electron density N crit established as a criterion for modification. XPS, Raman, and ReaxFF MD jointly confirmed phase separation, C-Si bond dissociation, and Si-O bond formation on the modified surface. A two-stage “modification-ablation” mechanism was further revealed: above the modification threshold, phase separation and formation of an amorphous oxide layer occur; above the ablation threshold, phase explosion and nanoparticle redeposition take place, accompanied by subsurface amorphization due to stress waves. Additionally, the systematic control of laser-induced periodic surface structures (LIPSS) via laser parameters was elucidated. By adjusting pulse fluence and overlap rate, a controllable evolution from low-spatial-frequency LIPSS to high-spatial-frequency LIPSS and nanoparticle composite structures was achieved, enabling effective modulation of surface stress distribution and stiffness. This study elucidates the intrinsic mechanisms by which femtosecond laser modification enhances SiC machinability from the perspectives of phase transformation and microstructure evolution, providing a theoretical basis for efficient, high-quality surface modification of hard and brittle wafers.
Source: openalex_inverted_index · Quality: baseline
Research context
OpenAlex topics: Laser Material Processing Techniques · Advanced Surface Polishing Techniques · Silicon Carbide Semiconductor Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (49)
Show source-provided references
1. Technology and applications of wide bandgap semiconductor materials: current state and future trends10.3390/en16186689 ↗
2. Recent advances and challenges in silicon carbide (SiC) ceramic nanoarchitectures and their applications
3. Paving the way toward the world's first 200mm SiC pilot line10.1016/j.mssp.2021.106088 ↗
4. Modulation of ultrafast laser-induced modified structure inside silicon carbide for thin wafer dicing10.1016/j.mssp.2024.108730 ↗
5. An investigation of recast behavior in laser ablation of 4H-silicon carbide wafer10.1016/j.mssp.2019.104701 ↗
6. Surface micromorphology and nanostructures evolution in hybrid laser processes of slicing and polishing single crystal 4H-SiC10.1016/j.jmst.2023.09.046 ↗
7. Chemical mechanical planarization (CMP) of on-axis Si-face SiC wafer using catalyst nanoparticles in slurry10.1016/j.surfcoat.2014.03.044 ↗
8. Atomic-scale finishing of carbon face of single crystal SiC by combination of thermal oxidation pretreatment and slurry polishing10.1016/j.apsusc.2017.10.159 ↗
9. UV-TiO2 photocatalysis-assisted chemical mechanical polishing 4H-SiC wafer10.1080/10426914.2017.1364855 ↗
10. Yamamura Atomic-scale flattening mechanism of 4H-SiC (0001) in plasma assisted polishing10.1016/j.cirp.2013.03.028 ↗
11. Effects of picosecond laser ablation and surface modification on the surface/interface characteristics and removal performance of 4H-SiC10.1016/j.jmst.2025.01.043 ↗
12. On enhancement of fracture resistance of adhesive joints by surface micropatterning using a femtosecond laser10.1016/j.jmatprotec.2023.117904 ↗
13. Laser-induced phase separation of silicon carbide10.1038/ncomms13562 ↗
14. Fabrication of through holes in silicon carbide using femtosecond laser irradiation and acid etching10.1016/j.apsusc.2013.11.030 ↗
15. An alternative approach for femtosecond laser induced black silicon in ambient air10.1016/j.apsusc.2012.08.087 ↗
16. Laser-induced periodic surface structures— A scientific evergreen10.1109/JSTQE.2016.2614183 ↗
17. Femtosecond laser surface modification of 4H-SiC improves machinability10.1016/j.apsusc.2023.156436 ↗
18. Analysis of the microscopic characteristics of periodic structure arrays on silicon carbide fabricated by femtosecond laser10.1016/j.ceramint.2023.10.212 ↗
19. Centimeter-scale low-damage micromachining on single-crystal 4H–SiC substrates using a femtosecond laser with square-shaped flat-top focus spots10.1016/j.ceramint.2021.05.027 ↗
20. Ensemble machine learning approach for evaluating the material characterization of carbon nanotube-reinforced cementitious composites
21. Grey wolf optimizer integrated within boosting algorithm: application in mechanical properties prediction of ultra high-performance concrete including carbon nanotubes
22. Machine learning based shear strength prediction in reinforced concrete beams using levy flight enhanced decision trees10.1038/s41598-025-12359-y ↗
23. A combined model for formation mechanism of ripples induced by femtosecond laser on silicon carbide10.1007/s00339-020-04004-4 ↗
24. Ultrafast pulsed laser stealth dicing of 4H-SiC wafer: structure evolution and defect generation10.1016/j.jmapro.2022.06.064 ↗
25. In’T Veld Two-temperature model for pulsed-laser-induced subsurface modifications in Si10.1007/s00339-013-7668-5 ↗
26. Removal of SiC at atomic and close-to-atomic scale by nanosecond ultraviolet laser10.1016/j.optlastec.2022.108863 ↗
27. Stress and crack dynamics in nanosecond laser slicing of silicon carbide
28. Innovative multiscale simulation with experimental validation of ultrafast laser processing in silicon carbide (4H-SiC)10.1016/j.jmapro.2025.02.002 ↗
29. Carrier lifetime variation in thick 4H-SiC epilayers using two-photon absorption10.1063/1.5001935 ↗
30. Experimental investigation on ablation of 4H-SiC by infrared femtosecond laser10.3390/mi13081291 ↗
31. The determination of high-density carrier plasma parameters in epitaxial layers, semi-insulating and heavily doped crystals of 4H-SiC by a picosecond four-wave mixing technique10.1088/0268-1242/21/7/021 ↗
32. Fast and slow carrier recombination transients in highly excited 4H–and 3C–SiC crystals at room temperature10.1063/1.3459894 ↗
33. ReaxFF molecular dynamics simulation of oxidation behavior of 3C-SiC in O2 and CO210.1016/j.commatsci.2021.110341 ↗
34. Fast parallel algorithms for short-range molecular dynamics10.1006/jcph.1995.1039 ↗
35. Visualization and analysis of atomistic simulation data with OVITO–the Open visualization tool10.1088/0965-0393/18/1/015012 ↗
36. Simple technique for measurements of pulsed Gaussian-beam spot sizes10.1364/OL.7.000196 ↗
37. Single-pulse femtosecond laser ablation of monocrystalline silicon: a modeling and experimental study10.1016/j.apsusc.2021.151722 ↗
38. Two novel SiC phases: structure, mechanical, and transport properties10.1088/2053-1591/abaafe ↗
39. Fokker-planck approach to laser-induced damage in dielectrics with subpicosecond pulses10.1080/15567260600901907 ↗
40. Maxwell meets marangoni—A review of theories on laser-induced periodic surface structures10.1002/lpor.202000215 ↗
41. Spatial characterization of doped SiC wafers by raman spectroscopy10.1063/1.368947 ↗
42. Oxidation of silicon carbide by O2 and H2O: a ReaxFF reactive molecular dynamics study, Part I10.1021/jp306391p ↗
43. A.C. van Duin high-temperature oxidation of SiC-based composite: rate constant calculation from ReaxFF MD simulations, Part II10.1021/jp307680t ↗
44. Tressler Oxidation kinetics of silicon carbide crystals and ceramics: i, in dry oxygen10.1111/j.1151-2916.1986.tb07470.x ↗
45. A study on crystallization of amorphous nano silica particles by mechanical activation at the presence of pure aluminum10.1016/j.jssc.2018.04.014 ↗
46. F. Fang Study on surface thermal oxidation of silicon carbide irradiated by pulsed laser using reactive molecular dynamics10.1063/5.0137778 ↗
47. Atomistic insights into ultrafast phase transitions driving nanoparticle formation in femtosecond laser–irradiated nickel-based superalloys
48. Femtosecond laser surface modification coupling with surface metallurgical reaction promotes surface plasticity of SiC10.1016/j.jmatprotec.2023.118077 ↗
49. Mechanism of tailoring laser-induced periodic surface structures on 4H-SiC crystal using ultrashort-pulse laser10.3390/nano15181398 ↗