UWBG Semiconductors–The Next Leap in RF and Power Electronics

Just as the wide bandgap (WBG) semiconductors, GaN and SiC, are revolutionizing RF and power electronics for defense and commercial applications, the unique properties of the ultra-wide bandgap (UWBG) semiconductors hold promise to create the next revolution. However, these materials are in their infancy, and many technical challenges must be overcome before their promise can become a reality. This invited talk will provide an overview of several UWBG research areas of interest to DARPA. These include: 1) methods to integrate dissimilar semiconductor materials, such as UWBG and narrow bandgap (NBG) semiconductors, to create new device structures that leverage the unique properties of the individual material layers, funded under the Heterogeneous Heterostructures (H2) program; 2) methods to integrate high thermal conductivity UWBG materials with WBG and NBG materials to overcome thermal and electric field bottlenecks in traditional RF power devices, funded under the Technologies for Heat Removal in Electronics at the Device Scale (THREADS) program; 3) new approaches to create large diameter, low defect density, single crystal diamond substrates, funded under the Large Area Device-Quality Diamond Substrates (LADDIS) program; 4) the synthesis of doped UWBG materials, the creation of novel UWBG heterostructures and the engineering of electrical and thermal interfaces funded under various smaller efforts; and 5) exploiting the high breakdown field of UWBG materials to achieve unprecedented levels of RF power handling.