The Application of Dynamical Thermal Annealing Processes after Mechanical Slicing as an Integrated Contactless SiC Wafering Method to Control Crystal Defects

We have developed a novel, material-lossless silicon carbide (SiC) wafer manufacturing process that eliminates the need for conventional grinding and polishing. Utilizing a thermal sublimation growth and etching technique called Dynamic AGE-ing ® (DA), we simultaneously performed thermal sublimation etching and growth on both the Si-face and C-face of single-crystal SiC wafers. This study investigated the impact of surface undulations—arising during DA planarization of as-sliced wafers with varying slicing qualities—on the densities of basal plane dislocations (BPDs) and in-grown stacking faults (IGSFs) in the epitaxial layers. Our findings demonstrate that larger pre-growth surface undulations correlate with higher BPD and IGSF densities in the DA-grown layers. By optimizing the initial wafer quality and DA process conditions, we achieved epitaxial layers with low defect densities (BPD density of 0.09 cm⁻² and IGSF density of 1.37 cm⁻²) without any material loss. This advancement offers a significant breakthrough in SiC device manufacturing, potentially reducing material costs and enhancing device performance by suppressing killer defects in the epitaxial layers.