Enhancement-Mode Heterojunction Vertical beta-Ga2O3 MOSFET with a P-Type Oxide Current-Blocking Layer

The vertical heterojunction Ga2O3 MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) with the p-type oxide as the current-blocking layer (CBL) is investigated for the first time using SILVACO simulation software. The results show that the threshold voltage of the device is easily positive, which means that the device works in the enhancement mode. By adjusting the doping concentration (from 2 x 10(17) cm(-3) to 2 x 10(18) cm(-3)) and thickness (from 0.4 um to 2 um) of p-SnO CBL, the threshold voltage is around from 2.4 V to 2.8 V and the breakdown voltage of the device can be increased from 361 V to 518 V. Compared with the original homojunction Ga2O3 vertical MOSFET with CBL, the p-SnO CBL can greatly improve the performance of the device. Other p-type oxides are also investigated as the CBL and show promising performances. This work has a certain guiding significance for the design of a vertical enhanced current-blocking layer MOSFET device and for the development of a Ga2O3 heterojunction power device.

Automated summary

The use of p-type oxide as the current-blocking layer in the vertical heterojunction Ga2O3 MOSFET greatly improves device performance. By adjusting the doping concentration and thickness, the threshold voltage and breakdown voltage can be modified. Furthermore, other p-type oxides show promising performances as well.