Abstract: Large-size polycrystalline silicon carbide （SiC） holds significant application prospects in the fields of semiconductor components， but its growth with high quality and large diameter remains challenges. This study employed the physical vapor transport （PVT） method to fabricate polycrystalline silicon carbide with a diameter of about 360 mm （approximately 14 inches， 1 inch=25.4 mm）. A series of characterization techniques were utilized to evaluate grain structure， crystal type， thermal conductivity， electrical resistivity， carrier concentration， and elastic modulus of polycrystalline silicon carbide. The results show that the as-fabricated polycrystalline silicon carbide exhibits a macroscopically crack-free surface and relatively uniform grain size distribution. The material crystal type is identified as 4H-SiC. The average thermal conductivity is approximately 323.8 W/（m·K）， the carrier concentration is on the order of 10¹⁷ cm^-3， and the elastic modulus ranges from 287 GPa to 311 GPa. This study demonstrates that large-size polycrystalline silicon carbide possesses uniform thermal conductivity and structural integrity， which is expected to meet the demand for cost-effective materials required for semiconductor components and other applications.

Key words: polycrystalline silicon carbide; physical vapor transport method; thermal conductivity; carrier concentration; elastic modulus