Resolving Critical Strain Gradients Induced by Laser Processing in SiC Wafer

Silicon carbide (SiC) is a hard, wide-bandgap semiconductor with excellent thermal conductivity and high breakdown electric field, making it ideal for power electronics and aerospace applications. Traditional SiC wafer production involves slicing and polishing, but a novel cold split technology has been developed to reduce material loss. This technique uses picosecond or nanosecond lasers to induce controlled subsurface cracks in SiC boules without surface damage. Rapid cooling then creates thermal stress to cleave the wafer. Laser parameters like wavelength, power, and pulse duration are critical in avoiding defects such as microcracks. However, the relationship between these parameters and wafer quality is not well understood. This proposal aims to map mosaicity and strain fields in laser-processed SiC using DFXM, exploring the correlation between laser conditions, damage zone characteristics, and final wafer properties.