The enhanced polarization relaxation and excellent high-temperature dielectric properties of N-doped SiC

The dielectric properties and microwave attenuation performance of N-doped SiC have been evaluated in 8.2–12.4 GHz in the temperature range of 293–673 K. The N doping dramatically improves the microwave absorption capability of SiC. The minimum reflection loss of N-doped SiC is enhanced to nearly −30 dB with the effective absorption bandwidth RL(dB) ≤ −10 dB up to 3 GHz at 673 K. The excellent high-temperature dielectric properties are attributed to multi-relaxations, originated from the polarization relaxations of dipoles induced by the N doping and vacancy defects.