Dielectric Property of Aluminum‐Doped SiC Powder by Solid‐State Reaction

The Al‐doped SiC powder was prepared by solid‐state reaction at 2000°C, using Al powder and SiC powder as the starting materials. The X‐ray diffraction patterns show that there is no impurity phase in the doped powder. The Raman spectra of doped SiC reveal that the intensities of all the characteristic peaks decrease, and both the 783 and 964 cm −1 peaks shift to a higher wavenumber. The electric permittivities of undoped and doped SiC samples were determined in the frequency range of 8.2–12.4 GHz. Results show that the real part ɛ′ and imaginary part ɛ″ of the complex permittivity of SiC powder are greatly improved through Al doping.