Investigation of Normally-Off β-Ga2O3 Power MOSFET Using Ferroelectric Gate

In this paper, we present a normally-off beta-gallium oxide (β-Ga2O3) metal–oxide–semiconductor field-effect transistor (MOSFET) with ferroelectric gate (Fe-G). The enhancement-mode (E-Mode) operations are achieved by depleting the charge carriers from the channel using the gate charge trapped in the ferroelectric material at the ferroelectric–dielectric (Fe-De) interface. The enhancement-mode (E-mode) operation has a negligible degradation in saturation current as compared to depletion-mode (D-Mode) operation. Ohmic-contacts access region resistances are minimized in the E-mode using highly-doped ohmic-contacts access regions. Furthermore, device achieves a significant low specific on-resistance (RON,sp) of 48 mΩ-cm2 in E-mode compared to 103 mΩ-cm2 in the D-mode. Furthermore, a high breakdown voltage (VBR) of 2250 V in E-mode combined with RON,sp brings in a figure of merit (VBR2/RON,sp) of 49 MW/cm2, showing its potential for futuristic wide bandgap (WBG) power devices. In addition, the E-mode device shows a hysteresis-free subthreshold swing (SS) of 65 mV/dec, which indicates its suitability for fast switching applications.