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

Abstract:

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.

• Periodical: Materials Science Forum (Volume 1157)
• Pages: 63-68
• DOI: https://doi.org/10.4028/p-QKqx1y
• Online since: September 2025
• Authors: Kohei Toda*, Daichi Dojima, Yuta Nakajima, Hiroshi Mihara, Tadaaki Kaneko
• Keywords: Annealing, C-Face, Dynamic AGE-ing^®, Machining Process, Material Loss, Multi-Wire Saw, Si-Face, Sublimation Controlled Etching, Sublimation Controlled Growth, Sub-Surface Damage, Thermal Etching

References

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