Semi-insulating silicon carbide (SiC) substrates serve as a critical material for the fabrication of high-frequency microwave devices, notably high electron mobility transistors (HEMTs). In comparison to traditional gallium arsenide (GaAs)-based devices, SiC-based RF components demonstrate superior high-frequency signal transmission, minimal signal loss, enhanced power capacity, and exceptional thermal stability. Communication systems incorporating these SiC RF devices exhibit significant advantages in signal fidelity, power efficiency, heat dissipation capability, and environmental adaptability. Consequently, they are extensively deployed in advanced applications including 5G/6G base stations, phased-array radars, satellite communication systems, vehicle-to-everything (V2X) networks, and defense electronic systems