The unique properties of wide- and ultrawide-bandgap semiconductors make them ideal for the next generation of power electronic devices and RF amplifiers. Their high critical electric field, in combination with excellent transport properties and high permittivity, allow for high voltage operation at high frequencies and small dimensions. This reduces parasitic capacitances and enables unprecedented efficiencies in applications such as power conversion in electric vehicles and smart grids, and record-high power densities and power added efficiencies in future 5G/6G wireless communications and radar systems. Furthermore, radiation hardened application for example for space borne systems are getting into the focus of interest.
In spite of the tremendous progress on wide-bandgap materials in the last few decades, devices made of these materials are still far from reaching their maximum theoretical performance, especially at high frequencies and voltage levels. In addition, new ultrawide-bandgap materials have the potential to improve this performance even further. To enable this, a better understanding of mobile carrier dynamics, charge transport, electron-hole recombination, and interaction with charged defects in dependence on specific operation conditions and mission profiles is needed, including supporting modelling and simulation. In addition, the new polytypes and reduced lattice symmetry in novel wide- and ultrawide-bandgap semiconductors enable new structure-property relationships and new design strategies to engineer the formation of two-dimensional carrier gases, as well as to tailor phonon-electron scattering band offsets through strain engineering in heteroepitaxy.
This APL Special Topic is intended to set a rapidly evolving stage for presenting the most recent results in this vibrant, fast paced, and potentially high impact scientific field.
Topics covered include, but are not limited to:
- Lateral and vertical devices including field effect and bipolar devices
- Thermal and electrical transport and thermal management
- Contact formation, gate dielectrics, and novel passivation technologies
- Sensitivity to ionizing radiation
- Electron and hole gases for innovative device concept
- Field emission devices
- High-frequency operation
- Hot electron and defect related trapping effects and degradation
- Efficient power devices
- High temperature performance and applications
Huili Grace Xing, Cornell University
Joachim Würfl, Ferdinand Braun Institute
Tomás Palacios, Massachusetts Institute of Technology
Yue Hao, Xidian University
Mathias Schubert, University of Nebraska-Lincoln