Demonstration of β-Ga₂O₃ Superjunction-Equivalent MOSFETs

In this work, we, for the first time, demonstrate beta-Ga2O3 lateral superjunction (SJ) -equivalent metal- oxide-semiconductor field-effect transistors (MOSFETs). The electric field engineering is implemented by the alternatively arranged p-NiO/n-Ga2O3 lateral hetero-SJ, which is constructed through the selective epitaxial filling of p-NiO pillars into the trenched drift region of beta-Ga2O3. The static electrical characteristics indicate that beta-Ga2O3 SJ-equivalent MOSFETs outperform the control transistor without the SJ structure. In particular, the Ga(2)O(3)SJ-equivalent MOSFET with a p-NiO pillar width of 2 1im demonstrates a breakdown voltage (V-br) of 1362 V and a power figure-ofmerit (PFOM) of 39 MW/cm(2), which are 2.42 and 4.86 times higher, respectively, than those of the control device. The large divergence of the experimental performance from the theoretical predictions is attributed to the charge imbalance caused by the substrate-assisted depletion effect and superimposed interfacial charges. With the proper interface engineering and controlled doping, it is expected that utilizing p-NiO/n-Ga2O3 hetero-SJ is a promising technological strategy to allow a favorable trade-off between V-br and oN-state loss of Ga2O3 transistors for the high-efficiency power conversion.