8 inch 4H-SiC seed was obtained by physical vapor transport (PVT) method with expansion of boule diameter from 6 inch. 8 inch conductivity type 4H-SiC crystal has been grown using 8 inch seed. 8 inch 4H-SiC substrate with a thickness of 520 μm was processed. Wafers were characterized by Raman spectroscopy, automatic microscope scanning, contactless resistivity measurement and high resolution X-ray diffraction (HRXRD). The polytype of whole wafer with the uniform color is 4H-SiC without other polytypes inclusions. Micropipe density is less than 0.3 cm-2. The resistivity range is from 20 mΩ·cm to 23 mΩ·cm, with an average value of 22 mΩ·cm. The full width at half maximum of the rocking curve of (004) diffraction peak is 32.7″, which indicates the good crystalline quality of the crystal．