【World Express】NASA Supports the Development of High-Voltage Gallium Oxide Power Devices: From High Breakdown Voltage to Reliability Validation in Space Environments

      High-voltage power electronics represent an important potential application area for gallium oxide. In aerospace applications, however, devices must do more than deliver excellent electrical performance; they must also withstand challenging environmental conditions, including high-energy particle radiation and temperature fluctuations. Translating the intrinsic advantages of gallium oxide into device capabilities that meet the demands of space missions has therefore become an important topic in gallium oxide research.

      A NASA-supported project, “High-Voltage Gallium Oxide Devices for Space Power Electronics” (Project No. 20027), is addressing these challenges. Led by CFD Research Corporation, in collaboration with the University at Buffalo, Vanderbilt University, and KYMA Technologies, the project investigates the radiation response, failure mechanisms, and radiation-tolerant design of high-voltage gallium oxide power MOSFETs, with the aim of exploring their potential applications in spacecraft power management and distribution systems.

      The significance of this research lies not only in expanding the potential application space for gallium oxide, but also in identifying key technical challenges that must be addressed before high-voltage gallium oxide devices can be deployed in demanding, high-reliability applications.

1.Gallium Oxide for Space Power Systems: Potential for High-Voltage Applications

      As NASA advances its science and space exploration missions, spacecraft and scientific instruments face increasingly demanding requirements for the efficiency, reliability, size, and weight of their power management and distribution (PMAD) systems. High-performance power electronic devices can help optimize power conversion and distribution, improving system efficiency while reducing overall size and weight.

      Gallium oxide (Ga₂O₃) is an ultra-wide-bandgap semiconductor with a high theoretical breakdown electric field, making it a promising material for high-voltage power electronics. Compared with conventional silicon-based power devices, gallium oxide devices have the potential to offer advantages in high-voltage operation and low conduction losses, providing an additional technological option for high-voltage power systems.

      These potential advantages are particularly relevant to space applications. According to the project description, radiation-tolerant gallium oxide power electronics capable of operating under high-voltage and high-temperature conditions could support power management and distribution systems in spacecraft and scientific instruments. The technology may also contribute to future missions involving lunar and planetary surface power systems and the Kilopower space nuclear power program.

      Nevertheless, the intrinsic advantages of a material do not automatically translate into devices that meet the requirements of space applications. For gallium oxide, ensuring stable device operation under demanding environmental conditions while maintaining its high-voltage performance remains a key challenge on the path from technological promise to practical application.

2.Beyond High Breakdown Voltage: Device Reliability and Radiation Tolerance

      High-energy particle radiation in space can affect the normal operation of electronic devices. For high-voltage power devices, single-event effects (SEEs) are of particular concern. When a high-energy particle interacts with a device, it can trigger transient electrical responses and, in severe cases, cause device failure.

      Temperature variations and device bias conditions can also influence electrical characteristics and radiation responses. Consequently, conventional electrical characterization alone is insufficient to fully assess a device's suitability for operation in the space environment.

      The NASA-supported project extends the investigation to device responses and reliability under radiation exposure. The research team aims not only to characterize device behavior under irradiation, but also to identify potential failure mechanisms and investigate how device structures and fabrication processes affect radiation tolerance.

      This research highlights an important development in gallium oxide device engineering: evaluation is expanding beyond conventional metrics, such as rated voltage and conduction characteristics, to encompass overall performance and reliability under specific operating environments.

3.Devices Rated Up to 8 kV: Investigating Failure Mechanisms Through Experiments and Modeling

      According to the project description, Phase I included single-event effect testing of gallium oxide power MOSFETs developed at the University at Buffalo, with device voltage ratings of up to 8 kV. The research team completed baseline electrical characterization, developed a technology computer-aided design (TCAD) model, and validated the model against experimental measurements.

      Building on this work, the team conducted single-event effect testing and corresponding simulations to investigate device responses under different device parameters and operating conditions. The researchers also identified technology-related and testing challenges requiring further investigation and established a technology development plan for the subsequent phase.

      Phase II plans to expand heavy-ion testing across different temperatures and bias conditions. More extensive parametric simulations will be conducted to investigate the mechanisms underlying radiation- and temperature-dependent responses and to identify design approaches that could improve device radiation tolerance.

      The project also plans to fabricate new baseline devices with improved layouts and packaging, develop radiation-tolerant MOSFET variants, and experimentally verify their electrical performance and radiation response. Expected deliverables include electrical and radiation-testing datasets, validated TCAD models, device design guidelines, and improved MOSFET prototypes.

4.From Laboratory Validation to Engineering Applications: Overcoming Reliability Challenges

      This project illustrates how the development of high-voltage gallium oxide power devices increasingly involves engineering challenges beyond intrinsic material properties.

      First, device performance must be matched to the target operating environment. High breakdown voltage is an important foundation for high-voltage power devices. However, in space power systems, radiation response, temperature tolerance, and long-term operational reliability also require systematic evaluation.

      Second, device design must be informed by an understanding of failure mechanisms. By combining experimental testing with TCAD modeling, researchers can investigate device responses under different operating conditions and establish a technical basis for structural optimization and radiation-tolerant design.

      In addition, manufacturability is an important step toward practical deployment. KYMA Technologies' participation in Phase II and subsequent development is intended to help ensure the manufacturability of gallium oxide power MOSFET technology for space applications. This reflects the project's broader focus on engineering development beyond laboratory device performance.

      The project sets a target technology readiness level (TRL) of 4 at the end of Phase II, corresponding to technology validation in a laboratory environment. This target indicates that further development and validation are needed before the technology can be considered for deployment in actual space missions.

5.Implications of NASA-Supported Research: Gallium Oxide Development Is Addressing More Specific Engineering Challenges

      The NASA-supported project provides a concrete example of the potential development of gallium oxide for high-reliability applications.

      On the one hand, the potential application space for gallium oxide is expanding beyond conventional high-voltage power electronics to specialized fields such as spacecraft power systems. On the other hand, these applications impose more stringent reliability requirements, making radiation effects, temperature tolerance, device optimization, and manufacturability important areas for continued research.

      For the gallium oxide community, the significance of this project extends beyond identifying a new potential application. It also illustrates the technical validation required to translate material advantages into practical engineering capabilities.

      As demand for high-voltage power electronics continues to grow across aerospace, energy, and other high-reliability applications, a key question for the future of gallium oxide is whether its intrinsic material properties can be translated into device performance that has been rigorously validated under the intended operating conditions.