SiC is a critical transparent material for the next-generation semiconductor industry. Its remarkable properties in turn challenge current processing techniques with cracking and chipping. We present a comparative study of 500 fs pulses (Pharos laser) vs externally compressed 50 fs pulses (n2-Photonics), showing drastically reduced chipping, cracking and heat affected zone of 4H-SiC-wafer.

Point ablation was compared for an energy density F = 52 J/cm² at a focal diameter of 22 µm with a Gaussian beam. The measured degradation around the ablation was significantly reduced for 50 fs ablation and f = 100 Hz for number of pulses n. No chipping or cracking was observed for 50 fs. For 500 fs chipping was observed after 10 pulses as well as cracking after 100 pulses.  Crossed-polarization imaging showed reduced stress after 1000 pulses on a single spot. For a practical application, a figure 8 was ablated with f = 25 kHz and F = 52 J/cm² at a high speed of 1500 mm/s, high resolution details were achieved whereas 500 fs lead to chipping, and cracking of the material in the crossing section of the figure. We demonstrated that reducing the pulse duration from 500 fs to 50 fs at 1030 nm prevents chipping and cracking, maintains a clean finish and resembles the behaviour of 500 fs, 343 nm UV pulse.