The metal oxide semiconductor gallium oxide is considered a promising candidate for potential use in power electronics. However, the targeted influencing of its electrical conductivity has been problematic to date. A research team involving the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has now investigated how the conductivity of gallium oxide in its most stable form (β-Ga2O3) can be controlled via the controlled incorporation of hydrogen into the crystal lattice.
A particularly striking property of the material is the ("ultra") width of its band gap, which promises applications in areas of high electric field strengths. However, the efficiency of conventional doping processes decreases as the band gap energy increases.
In bipolar transistors, n- and p-doped layers are combined in such a way that a larger current flow can be controlled with the aid of a small control current. Until now, two different materials have been combined to create the two layers, but the team was able to achieve this by incorporating hydrogen into the crystal lattice in a single material. With only a small amount of hydrogen incorporated, the material behaves like a p-doped semiconductor, while the addition of more hydrogen leads to switching to the n-conduction mode.
