AlInN-GaN Vertical Power Electronic Devices

Nontechnical:

Power electronics require materials that can withstand high voltages and currents. Ultrawide bandgap semiconductors have the potential to fulfill this role. Unlike conventional semiconductors that absorb visible and near infrared light, ultrawide bandgap semiconductors are transparent to visible light and absorb in the ultraviolet.

These properties also allow them to be used in devices that operate at high temperatures and voltages, which is crucial for power electronics. This project researches methods to create advanced power electronics using an ultrawide bandgap semiconductor, aluminum indium nitride (AlInN). AlInN, used in combination with gallium nitride, has the potential to produce high performance power electronic devices.

AlInN-based power devices will lead to a reduction in the size, weight, and power of electrical systems. Power devices created in this program will positively impact the nation's economy and increase energy efficiency. Graduate students will be trained in the essential areas of advanced semiconductor materials synthesis, materials and device physics, and device fabrication and design.

The topics of this program will be integrated into graduate and undergraduate courses to broaden students' educational experience beyond the laboratory. They will also be incorporated into K-12 education and outreach activities. Technical:

This program explores aluminum indium nitride/gallium nitride (AlInN/GaN) for vertical power electronic devices with superior performance over state-of-the-art technologies based on GaN. AlInN is in the ultra-wide bandgap class of semiconductors with desirable device properties such as a lattice-matched substrate (GaN), high electron mobility, n- and p-type doping, useful GaN/AlInN heterointerfaces, and the ability to create a native oxide.

The program has two thrusts. The first is to investigate AlInN as drift layers for power diodes by advancing the state-of-the-art growth of AlInN; designing novel edge termination structures; fabricating and testing AlInN power diodes; and measuring fundamental properties such as impact ionization. The second is to create 3-terminal AlInN-based power devices such as junction field-effect transistors (JFETs) and metal oxide semiconductor field-effect transistors (MOSFETs) by investigating the insulating and charge properties of the AlInN native oxide; using the oxide to create novel device architectures; using technology computer-aided design (TCAD) modeling to guide device decisions; and fabricating and testing transistors.

The program has broad goals of creating experimental methods for AlInN-based power devices and gain a deep understanding of the physics of AlInN and its devices.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.