High Temperature AlInGaN-based Heterostructure Field Effect Transistors Over Intrinsic Semi-insulating 6H-SiC Substrates

We will develop commercially viable quaternary AlInGaN-based epitaxial wafer technology on semi-insulating 6H-SiC for manufacturing of reliable high microwave power, high operation temperature (300 oC and higher) transistors and amplifiers for newgeneration of T/R modules. We will use our proprietary MOCVD growth technology and unique buffer layer design to deposit quaternary AlInGaN-based Double Heterostructure Field Effect Transistor (DHFET) structures with InGaN channels on intrinsicallysemi-insulating 6H-SiC substrates under development at II-VI, Inc. This will allow us to combine the advantages of DHFET design (current collapse-free performance) with superior transport properties and high temperature performance of epilayers grown over6H-SiC substrates. We will fabricate and test the device performance at elevated temperatures up to 350 oC in order to optimize epilayer design and suppress RF power degradation. We expect that these substrates will exhibit major improvements inperformance of high power microwave devices at elevated temperatures. In Phase I, we will demonstrate DHFET epilayers with carrier sheet density time mobility in excess of 1016 V-1s-1 grown on intrinsic semi-insulating 6H-SiC substrates. We will fabricatesmall periphery DHFETs grown over semi-insulating 6H-SiC substrates with and without Vanadium doping. We will study high temperature RF characteristics of the devices deposited on both types of substrates under similar conditions (in a single growth run).In Phase II, jointly with II-VI, Inc. we will scale-up wafer growth technology on 2