AlGaN/GaN Schottky Barrier Diodes on Free-Standing GaN Substrates With a Si Doped Barrier Layer

This paper presented a AlGaN/GaN Schottky barrier diodes (SBDs) on free-standing GaN substrates with a Si doped barrier layer were fabricated for high power application. Compared with the conventional SBDs, the SBDs with doped barrier layer have the lower turn-on voltage ( $V_{ON}$ ) and specific on resistance ( R_{ON_SP} ) because more free carriers are induced in two-dimensional electron gas (2DEG) channel. With Si doping concentration of $1 \times 10^{20}$ cm ⁻³ for AlGaN barrier layer, the SBDs demonstrate R_{ON_SP} of 0.12 m $\Omega \cdot \mathrm{cm^{2}}$ , $V_{ON}$ of 0.41 V, breakdown voltage of 339 V, and power figure-of-merit ( PFOM ) of 957.6 MV/cm ² , which have a great potential for high-speed power device applications. Meanwhile, the SBDs with doped barrier have a faster reverse recovery time, and a better low-frequency noise (LFN) characteristics at low current density due to high carrier mobility and less generation-recombination (G-R) noise.