Slicing of 4H‐SiC Wafers Combining Ultrafast Laser Irradiation and Bandgap‐Selective Photo‐Electrochemical Exfoliation

High-efficiency and low-loss processing is the mainstay to reduce cost deepen application of 4H silicon carbide (4H-SiC) wafers in high-power high-frequency electronics. In this study, high-yield slicing 4H-SiC realized by combining femtosecond laser irradiation bandgap-selective photo-electrochemical (PEC) exfoliation. By light-absorption measurements, micro-Raman, micro-photoluminescence characterizations, it found that damage layer formed inside after femtosecond-laser consists amorphous carbon. This indicates leads phase separation 4H-SiC. The bandgap 0.4 eV. Taking advantage different energies perfect region, removed from region using PEC etching. During etching, light-generated holes can selectively oxidize corrode damaged with assistance HF solution, leave upper lower layers being intact. current work contributes development high-throughput wafers.