  The emerging wide bandgap BAlN alloys have potentials for improved
III-nitride power devices including high electron mobility transistor (HEMT).
Yet few relevant studies have been carried. In this work, we have investigated
the use of the B0.14Al0.86N alloy as part or entirety of the interlayer between
the GaN buffer and the AlGaN barrier in the conventional GaN-based high
electron mobility transistor (HEMT). The numerical results show considerable
improvement of the two-dimensional electron gas (2DEG) concentration with small
2DEG leakage into the ternary layer by replacing the conventional AlN
interlayer by either the B0.14Al0.86N interlayer or the B0.14Al0.86N/AlN hybrid
interlayer. Consequently, the transfer characteristics can be improved. The
saturation current can be enhanced as well. For instance, the saturation
currents for HEMTs with the 0.5 nm B0.14Al0.86N/0.5 nm AlN hybrid interlayer
and the 1 nm B0.14Al0.86N interlayer are 5.8% and 2.2% higher than that for the
AlN interlayer when VGS-Vth= +3 V.
