Epitaxial regrowth and characterizations of vertical GaN transistors on silicon.

We report the fabrication of fully-vertical GaN-based metal-oxide-semiconductor field-effect transistors (V-MOSFETs) on Si. A p-GaN current aperture was introduced in the vertical device epi-structure using plasma-based dry etching and epitaxial regrowth technique to control the vertical current conduction. The fabricated V-MOSFET exhibited drain current density of 2.5 kA cm⁻² with ON-resistance (R_ON) of 4.3 mΩ-cm². The transfer characteristics of the device showed a peak trans-conductance (G_m,max) of 248 S cm⁻² with a threshold voltage (V_th) of −18.7 V during OFF-to-ON-state sweeping. However, a blocking voltage of 36.5 V (drain current density 0.3 kA cm⁻²) was observed under an OFF-state condition of the device which needs further improvement for the high-power device applications. [ABSTRACT FROM AUTHOR]