A Novel Process For Growth of High Quality Semi-insulating SiC Crystals

Silicon carbide (SiC) is the most promising substrate material for the next generation high power, high frequency power transistors replacing traveling wave tube for radar power applications. Such devices in both, group III nitrides (III-N) and SiC havebeen under development for these applications. SiC possesses advantages that are unmatched by any other substrate for both III-N and SiC based devices. High frequency power transistors fabricated on semi-insulating silicon carbide (SI-SiC) substrates (viaheteroepitaxy or homoepitaxy) will benefit significantly from the substrate's high thermal conductivity to dissipate heat generated during operation. Devices made on SI-SiC substrates have an added advantage of increased frequency performance due to thelower parasitic losses compared to conducting substrates. In addition, SiC is well suited for growth of III-nitrides due to its small lattice mismatch. Reduced lattice mismatch is critical in achieving low defect density layers in heteroepitaxial growth.