Growth of thick AlGaN epitaxial layer for High Power Heterostructure Field Effect Transistors On Semi-insulating 6H-SiC Substrates

Increasing the GaN and AlGaN thickness is crucial for improved material quality and, thus, increased microwave output and enhanced reliability of high-power devices. We will use our proprietary growth technology and unique buffer layer design to depositthick GaN and AlGaN templates for quaternary AlInGaN-based Heterostructure Field Effect Transistor (HFET) structures on semi-insulating 6H-SiC substrates supplied by II-VI, Inc. This will allow us to combine the advantages of thick GaN template withsuperior thermal properties of epilayers grown over 6H-SiC substrates. We will develop a fast growth MOCVD technology and perform detailed material/substrate interaction studies to optimize growth conditions in order to achieve thick high quality materialto obtain maximum RF output power along with lowest RF power degradation. The proposed technology would combine the advantages of thick GaN template with superior thermal properties of epilayers grown over 6H-SiC substrates. Our approach will be used todevelop commercially viable thick GaN and AlGaN epitaxial wafer technology on semi-insulating 6H-SiC for manufacturing of reliable high microwave power transistors and amplifiers for new generation of radars and wireless communication systems.