Unipolar <i>β</i>-Ga2O3 Pseudo-junction barrier Schottky diodes via Low-Cost magnesium diffusion process

Beta Gallium Oxide (β-Ga2O3) Junction Barrier Schottky diodes possess excellent breakdown characteristics and efficiency, but the lack of p-type β-Ga2O3 has led to the use of alternative materials, such as NiOx, which pose challenges regarding lattice mismatch and temperature stability. This work reports a unipolar β-Ga2O3 diode enabled by the magnesium (Mg) diffusion process to create high-resistance electron-blocking regions. The Mg diffusion process developed in this work uses a room temperature compatible chemical process followed by an 800 °C annealing step, which is lower compared to already reported methods in the literature. Therefore, the proposed method is thought to reduce the device processing temperature budget and hence cost. The resulting device achieves an Ion/Ioff ratio of ∼109, a knee voltage of ∼0.9 V, and a breakdown voltage of 596 V. In addition, it demonstrates stable operation from 100 to 500 K, highlighting its suitability for electronics operating across a broad temperature range.