High Purity SiC Powder for Wafer Industry Research Report 2026

Definition

High-purity SiC powder for wafer growth is a stoichiometric, ultra-clean silicon carbide feedstock engineered as the sublimation source in seeded physical vapor transport (PVT) growth of 4H/6H-SiC boules for power and RF wafers. It is produced from high-purity precursors (e.g., carbothermal reduction of electronic-grade silica and carbon or gas-phase synthesis), then de-metalized and de-oxygenated by high-temperature halogen treatments, acid leaching, and calcination, and finally classified to a narrow, coarse granular distribution that packs stably in graphite crucibles while providing predictable mass transport. Typical specifications target 5N–6N total purity with transition metals in the sub-ppm range, oxygen and nitrogen at a few ppm or lower, and free Si/C below 0.1 wt%, with controlled bulk density, BET surface area, and residual volatiles to suppress parasitic nucleation and crusting. Morphology and porosity are tuned to maintain a steady source recession rate and constant C/Si vapor ratio across the growth run, enabling low-defect boules with controlled background doping; dopant-tailored variants may incorporate trace N or Al for n-/p-type control. As a polytype-neutral source whose function is to deliver chemically clean, compositionally stable Si-C vapor under high temperature and low pressure, it is distinguished from abrasive or ceramic-grade SiC powders by its electronic-materials impurity budget, degassing behavior, and reproducibility in long-duration PVT processes.