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arXiv · 2306.01115

Native defect association in beta-Ga2O3 enables room-temperature p-type conductivity

Zeyu Chi·Corinne Sartel·Yunlin Zheng·Sushrut Modak·Leonid Chernyak·Christian M Schaefer·Jessica Padilla·Jose Santiso·Arie Ruzin·Anne-Marie Goncalves·Jurgen von Bardeleben·Gerard Guillot·Yves Dumont·Amador Perez-Tomas·Ekaterine Chikoidze
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Abstract

The room temperature hole conductivity of the ultra wide bandgap semiconductor beta Ga2O3 is a pre-requisite for developing the next-generation electronic and optoelectronic devices based on this oxide. In this work, high-quality p-type beta-Ga2O3 thin films grown on r-plane sapphire substrate by metalorganic chemical vapor deposition (MOCVD) exhibit Rho = 50000Ohm.cm resistivity at room temperature. A low activation energy of conductivity as Ea2=170 meV was determined, associated to the oxygen - gallium native acceptor defect complex. Further, taking advantage of cation (Zn) doping, the conductivity of Ga2O3:Zn film was remarkably increased by three orders of magnitude, showing a long-time stable room-temperature hole conductivity with the conductivity activation energy of around 86 meV.

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Zeyu Chi, Corinne Sartel, Yunlin Zheng, Sushrut Modak, Leonid Chernyak, Christian M Schaefer, Jessica Padilla, Jose Santiso, Arie Ruzin, Anne-Marie Goncalves, Jurgen von Bardeleben, Gerard Guillot, Yves Dumont, Amador Perez-Tomas, Ekaterine Chikoidze. 2023-06-01. Native defect association in beta-Ga2O3 enables room-temperature p-type conductivity. https://arxiv.org/abs/2306.01115

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