Defect control in Gallium Oxide for next gen POWer electronics (GO-POW)
The primary goal of GO-POW is to use advanced first-principles defect modelling in close combination with junction- and optical spectroscopy techniques to accelerate the development of Ga2O3 as a material for power electronics, and as a predictive tool for defect engineering.
About the project
Power electronics is an integral part of all electric systems. It is used to convert electricity between alternating and direct current, and to change between high and low voltage levels. Power electronics is thus a key element in the power grid itself, but also central in providing power, e.g., from solar cells and wind-turbines into the grid. It is also central in charging electric vehicles and the transmission of power from the batteries to the motor. We also find them in all our electric appliances in our homes, like in electric stoves, mobile phones, and computers to mention a few. Thus, power electronics is a key enabler in realizing an electrification of our societies. GO-POW will address the need to understand key and fundamental defects in the material Ga2O3. This is a material with high potential future impact in next-generation power electronics. There are two key benefits: (i) the ability to withstand high electric fields, owing to its ultra-wide electronic band gap and (ii) the possibility to control the electrical conductivity over a wide range. The improved ability to withstand electric fields, opens the possibility to reduce the thickness of the active material, which in turn will reduce the dissipation of heat, permitting devices that are faster, smaller and more energy efficient. However, to realize these possibilities it is critical to improve the knowledge of point defects of this material.
The objectives of GO-POW can be divided into two stages:
- To radically increase the understanding of point defects in β-Ga2O3 through a combined effort of advanced first-principles defect modelling and experimental defect spectroscopic techniques. A special focus will be on so-called bi-stable defects, which can be detrimental to device performance, as well as technologically important impurities and dopants. GO-POW aims to characterize and identify electrical and optical defect signatures, and to understand impurity diffusion and the interaction between defects in the material.
- The achieved accuracy of the above approach will be used to develop a “sandbox” for defect engineering in β-Ga2O3, and then expand into novel related materials systems.
The GO-POW project consists of four work scientific packages:
- Electrical characterization, identification, and control of bi-stable defects.
- Defect origin of the visible broad luminescence bands.
- Impurity diffusion and defect interaction.
- Defect engineering and novel materials.
The project is financed by the Research Council of Norway (no. 314017)
Frodason, Ymir Kalmann; Zimmermann, Christian; Verhoeven, Espen Førdestrøm; Weiser, Philip Michael; Vines, Lasse & Varley, Joel Basile (2021). Multistability of Ga-O divacancies in β-Ga2O3.
Krzyzaniak, Patryk Piotr; Frodason, Ymir Kalmann; Weiser, Philip Michael; Vines, Lasse & Johansen, Klaus Magnus H (2021). Diffusion of donor dopants in β-Ga2O3 and interplay with gallium vacancies.
Zimmermann, Christian; Frodason, Ymir Kalmann; Varley, Joel Basile; Verhoeven, Espen Førdestrøm; Rønning, Vegard & Weiser, Philip Michael [Show all 15 contributors for this article] (2021). Identification of Fe-, Ti- and H-related Charge-state Transition Levels in β-Ga2O3.
Langørgen, Amanda; Karsthof, Robert Michael; Weiser, Philip Michael; Cavani, Olivier; Grasset, Romain & Frodason, Ymir Kalmann [Show all 8 contributors for this article] (2021). Steady-state Photocapacitance Spectroscopy of Intrinsic Defects in Electron-Irradiated β-Ga₂O₃.
Krzyzaniak, Patryk Piotr; Vines, Lasse & Johansen, Klaus Magnus H (2021). Development of b-Ga2O3 as a novel material for power electronics, dopant diffusion and defect interaction. UiO.