An E-mode $\beta$-Ga2O3 metal-heterojunction composite field effect transistor with a record high P-FOM of 0.73 GW/cm2

In this work, a $\beta$-Ga2O3 metal-heterojunction composite field effect transistor (ME-HJFET) has been proposed that combines the merits of both the Schottky gate, as well as the NiOX pn heterojunction gate. Meanwhile, a conventional heterojunction field effect transistor (CHJ-FET) has been fabricated. The study addresses the critical metrics of BV (breakdown voltage) and specific on-resistance ($R_{\text{ON},\text{SP}}$) and at the same time achieves a significant improvement of these parameters in comparison to the previously reported state-of-the-art designs. A high breakdown voltage (BV) of around 2160 V and an RON, SP of $6.35\ \mathrm{m}\Omega\cdot\text{cm}^{2}$ for ME-HJFET and a BV of around 2340 V and an RON, SP of $21.9\ \mathrm{m}\Omega\cdot\text{cm}^{2}$ for CHJ-FET were achieved. Also, a P-FOM of 0.73 GW/cm² was achieved, which is near twice the value for a CHJ-FET (0.37 GW/cm²). This is also the highest value reported so far for any E-mode Ga2O3 FETs.