Research in ultra-wide-bandgap (UWBG) semiconductor materials and devices continues to progress rapidly, providing new and exciting research opportunities for a wide range of electronic, optical, sensing and quantum applications. Materials with bandgaps exceeding that of GaN and SiC, such as GaO/AlGaO, diamond, c-BN and AlGaN are at the frontier of semiconductor materials research and device physics. Many of the fundamental properties of these emerging materials are still poorly understood; however, as an example, the physics of high-energy carrier scattering and transport processes responsible for electrical breakdown are largely unknown. Practical challenges such as efficient and controllable n-type and p-type doping, production of large area, low defect density substrates, the formation of reliable, low resistance electrical contacts and the integration of dielectric films with high quality interfaces are also yet to be sufficiently addressed to facilitate the delivery of mature, viable and cost competitive UWBG technologies. While such materials hold great promise for applications ranging from UV emitters/detectors, to more compact and efficient energy converters, to higher-power high-frequency amplifiers, to advances in quantum information science, many materials and processing challenges must be addressed before such UWBG semiconductors can reach maturity and have significant impact. This symposium will cover comprehensive topics related to the materials science, device physics, and processing of UWBG materials, with a perspective on the applications that are driving research in the field. Topics of current interest in the more traditional wide-bandgap materials will also be considered. In this symposium, we will arrange a special session focusing on vertical GaN power devices targeting high-voltage operation, in coordination with DOE’s Advanced Research Projects Agency, ARPA-E. Approaches to addressing specific challenges in GaN, such as the epitaxial growth of thick, low-doped drift layers and the realization of selective-area doping, will be covered.

chemical vapor deposition (CVD) (deposition) crystal growth dielectric properties electrical properties epitaxy molecular beam epitaxy (MBE) nucleation & growth radiation effects reactive ion etching thermal conductivity