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

Abstract

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 (RON_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 RON_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/cm2, 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.

Keywords

• AlGaN/GaN
• Schottky barrier diode
• Si doped
• AlGaN barrier layer